These near-infrared images, taken with the Near-Infrared Camera and Multi-Object Spectrometer (NICMOS) aboard NASA's Hubble Space Telescope, show the wing- shaped dust disk surrounding the young, nearby star HD 61005. Astronomers have dubbed the star system "The Moth" because the dust disk resembles the wings of the flying insect.

The Moth's wingspan extends about 22 billion miles from the star. The black disk in the center of the images represents the coronagraphic hole in the NICMOS camera that blocks most of the starlight so that astronomers can see details in the surrounding dust disk.

HD 61005 is about 100 million years old. Dust disks around stars of The Moth's age are typically flat structures where planets can form. These Hubble images show that some dust disks have some surprising shapes. HD 61005 appears to be plowing through a local patch of higher-density gas in the interstellar medium, causing material in the HD 61005's disk to be swept behind the star.

HD 61005 resides 100 light-years from Earth. NICMOS took these images in 2005 and 2006.

This loose collection of stars is actually a dwarf irregular galaxy, called Holmberg IX. It resides just off the outer edge of M81, a large spiral galaxy in Ursa Major. This image was taken with Hubble's Advanced Camera for Surveys in early 2006. Holmberg IX is of the so-called Magellanic type of galaxy, as its size and irregularity in structure are similar to the Small Magellanic Cloud, a neighbor to our own Milky Way. Holmberg IX was first discovered by astronomer Sidney van den Bergh in 1959, and cataloged as DDO 66. The galaxy received its "Holmberg IX" naming when it was discussed in Eric Holmberg's study of groups of galaxies ten years later. It is suspected that the dwarf galaxy was created as a result of a galactic interaction between M81 and neighboring galaxy M82.

Of the more than 20,000 stars that can be resolved in this Hubble image, only about 10 percent are considered to be old stars with ages of billions of years. The rest are thought to be young stars with ages of only 10 to 200 million years. Due to the Advanced Camera for Surveys' resolution in this image, astronomers have noted that the old and the young stars have distinct spatial distributions which might be related to their origin.

Simulations predict that the triplet M81, M82, and nearby NGC 3077 had a close passage 200 to 300 million years ago. This close encounter may have triggered the newer star formation that has occurred in Holmberg IX.

The bluish-white fuzz in the space surrounding M81 and Holmberg IX is new star formation triggered by gravitational interactions between the two galaxies. There are many low mass galaxies that form stars in nearby space. While none of these are as dominated by recently produced stars as Holmberg IX, they might be related to the same family. By understanding how Holmberg IX was formed, scientists hope to understand their role as building blocks of large galaxies.

These images reveal the distribution of dark matter in the supercluster Abell 901/902, composed of hundreds of galaxies.

The image in the center shows the entire supercluster. Astronomers assembled this photo by combining a visible-light image of the supercluster taken with the MPG/ESO 2.2-meter telescope in La Silla, Chile, with a dark matter map derived from observations with NASA's Hubble Space Telescope.

The magenta-tinted clumps represent a map of the dark matter in the cluster. Dark matter is an invisible form of matter that accounts for most of the universe's mass. The image shows that the supercluster galaxies lie within the clumps of dark matter.

Hubble cannot see the dark matter directly. Astronomers inferred its location by analyzing the effect of so-called weak gravitational lensing, where light from more than 60,000 galaxies behind Abell 901/902 is distorted by intervening matter within the cluster. Researchers used the observed, subtle distortion of the galaxies' shapes to reconstruct the dark matter distribution in the supercluster. The image was assembled by combining a visible-light image of the supercluster with a map of the dark matter distribution.

The Hubble study pinpointed four main areas in the supercluster where dark matter has pooled into dense clumps. These areas match the location of hundreds of galaxies that have experienced a violent history in their passage from the outskirts of the supercluster into these dense regions. The four close-up images flanking the central photo are Hubble views of the four dense clumps of matter. To make this image, astronomers superimposed the dark matter map over a Hubble visible-light image of the supercluster galaxies.

The images are part of the Space Telescope Abell 901/902 Galaxy Evolution Survey (STAGES), which covers one of the largest patches of sky ever observed by the Hubble telescope. The area surveyed is so wide that it took 80 Hubble images to cover the entire field.

Hubble's Advanced Camera for Surveys made the observations in June and July 2005 and in January 2006.

Astronomers assembled this photo by combining a visible-light image of the Abell 901/902 supercluster taken with the MPG/ESO 2.2-meter telescope in La Silla, Chile, with a dark matter map derived from observations with NASA's Hubble Space Telescope. The magenta-tinted clumps represent a map of the dark matter in the cluster. Dark matter is an invisible form of matter that accounts for most of the universe's mass. The image shows that the supercluster galaxies lie within the clumps of dark matter.

Hubble cannot see the dark matter directly. Astronomers inferred its location by analyzing the effect of so-called weak gravitational lensing, where light from more than 60,000 galaxies behind Abell 901/902 is distorted by intervening matter within the cluster. Researchers used the observed, subtle distortion of the galaxies' shapes to reconstruct the dark matter distribution in the supercluster.

This is an image of gravitational lens system SDSSJ0946+1006 as photographed by Hubble Space Telescope's Advanced Camera for Surveys. The gravitational field of an elliptical galaxy warps the light of two galaxies exactly behind it. The massive foreground galaxy is almost perfectly aligned in the sky with two background galaxies at different distances. The foreground galaxy is 3 billion light-years away, the inner ring and outer ring are comprised of multiple images of two galaxies at a distance of 6 and approximately 11 billion light-years. The odds of seeing such a special alignment are estimated to be 1 in 10,000. The right panel is a zoom onto the lens showing two concentric partial ring-like structures after subtracting the glare of the central, foreground galaxy.

This is an image of gravitational lens system SDSSJ0946+1006 as photographed by Hubble Space Telescope's Advanced Camera for Surveys.

The gravitational field of an elliptical galaxy warps the light of two galaxies exactly behind it. The massive foreground galaxy is almost perfectly aligned in the sky with two background galaxies at different distances. The foreground galaxy is 3 billion light-years away, the inner ring and outer ring are comprised of multiple images of two galaxies at a distance of 6 and approximately 11 billion light-years. The odds of seeing such a special alignment are estimated to be 1 in 10,000.

This is a zoom onto the Hubble Space Telescope Advanced Camera for Surveys image of gravitational lens system SDSSJ0946+1006, showing two concentric partial ring-like structures after subtracting the glare of the central, foreground galaxy.

Detailed analysis of two continent-sized storms that erupted in Jupiter's atmosphere in March 2007 shows that Jupiter's internal heat plays a significant role in generating atmospheric disturbances. Understanding this outbreak could be the key to unlock the mysteries buried in the deep Jovian atmosphere, say astronomers.

Understanding these phenomena is important for Earth's meteorology where storms are present everywhere and jet streams dominate the atmospheric circulation. Jupiter is a natural laboratory where atmospheric scientists study the nature and interplay of the intense jets and severe atmospheric phenomena.

An international team coordinated by Agustin Sánchez-Lavega from the Universidad del País Vasco in Spain presents its findings about this event in the January 24 issue of the journal Nature.

The team monitored the new eruption of cloud activity and its evolution with an unprecedented resolution using NASA's Hubble Space Telescope, the NASA Infrared Telescope Facility in Hawaii, and telescopes in the Canary Islands (Spain). A network of smaller telescopes around the world also supported these observations.

According to the analysis, the bright plumes were storm systems triggered in Jupiter's deep water clouds that moved upward in the atmosphere vigorously and injected a fresh mixture of ammonia ice and water about 20 miles (30 kilometers) above the visible clouds. The storms moved in the peak of a jet stream in Jupiter's atmosphere at 375 miles per hour (600 kilometers per hour). Models of the disturbance indicate that the jet stream extends deep in the buried atmosphere of Jupiter, more than 60 miles (approximately100 kilometers) below the cloud tops where most sunlight is absorbed.

For additional information, contact:

Ray Villard
Space Telescope Science Institute, Baltimore, Md.
410-338-4514
villard@stsci.edu

Carolina Carnalla-Martinez
Jet Propulsion Laboratory, Pasadena, Calif
818-354-9382
carnalla@jpl.nasa.gov

Agustin Sánchez-Lavega
Universidad del País Vasco, Spain
011-34-94-601-4255
agustin.sanchez@ehu.es

An image of Jupiter in visible-light from NASA's Hubble Space Telescope (HST) on May 11, 2007 showing the turbulent pattern generated by the two plumes at the upper left part of Jupiter.

The background image is from Hubble Space Telescope and shows the turbulent pattern generated by the two plumes on May 11, 2007 (upper left part of Jupiter). The two bright plumes detach in the superimposed small infrared image obtained at the NASA-IRTF facility a month before, on April 5, 2007.

The elliptical galaxy NGC 1132 reveals the final result of what may have been a group of galaxies that merged together in the recent past. Another possibility is that the galaxy formed in isolation as a "lone wolf" in a universe ablaze with galaxy groups and clusters.

NGC 1132 is dubbed a "fossil group" because it contains enormous concentrations of dark matter, comparable to the dark matter found in an entire group of galaxies. NGC 1132 also has a strong X-ray glow from an abundant amount of hot gas that is normally only found in galaxy groups.

In visible light, however, it appears as a single, isolated, large elliptical galaxy. The origin of fossil-group systems remains a puzzle. They may be the end-products of complete merging of galaxies within once-normal groups. Or, they may be very rare objects that formed in a region or period of time where the growth of moderate-sized galaxies was somehow suppressed, and only one large galaxy formed.

Elliptical galaxies are smooth and featureless. Containing hundreds of millions to trillions of stars, they range from nearly spherical to very elongated shapes. Their overall yellowish color comes from the aging stars. Because ellipticals do not contain much cool gas, they no longer can make new stars.

This image of NGC 1132 was taken with Hubble's Advanced Camera for Surveys. Data obtained in 2005 and 2006 through green and near-infrared filters were used in the composite. In this Hubble image, NGC 1132 is seen among a number of smaller dwarf galaxies of similar color. In the background, there is a stunning tapestry of numerous galaxies that are much larger but much farther away.

NGC 1132 is located approximately 318 million light-years away in the constellation Eridanus, the River.

For more information, please contact:

Ray Villard
Space Telescope Science Institute, Baltimore, Md.
410-338-4514
villard@stsci.edu

Lars Lindberg Christensen
Hubble/ESA, Garching, Germany
011-49-89-3200-6306
lars@eso.org

Michael West
ESO, Santiago, Chile
011-56-2-463-3254
mwest@eso.org

This image of the elliptical galaxy NGC 1132 combines an image from NASA's Chandra X-Ray Observatory obtained in 2004 with images from the Hubble Space Telescope made in 2005 and 2006 in green and near-infrared light. The blue/purple in the image is the X-ray glow from hot, diffuse gas. The giant foreground galaxy, numerous dwarf galaxies in its neighborhood, and many much more distant galaxies in the background are seen in visible light.

This image of the elliptical galaxy NGC 1132 combines an image from NASA's /Chandra X-Ray Observatory/ obtained in 2004 with images from the /Hubble Space Telescope/ made in 2005 and 2006 in green and near-infrared light. The blue/purple in the image is the X-ray glow from hot, diffuse gas. The giant foreground galaxy, numerous dwarf galaxies in its neighborhood, and many much more distant galaxies in the background are seen in visible light.

A massive cluster of yellowish galaxies is seemingly caught in a spider web of eerily distorted background galaxies in the left-hand image, taken with the Advanced Camera for Surveys (ACS) aboard NASA's Hubble Space Telescope.

The gravity of the cluster's trillion stars acts as a cosmic "zoom lens," bending and magnifying the light of the galaxies located far behind it, a technique called gravitational lensing. The faraway galaxies appear in the Hubble image as arc-shaped objects around the cluster, named Abell 1689. The increased magnification allows astronomers to study remote galaxies in greater detail.

One galaxy is so far away, however, it does not show up in the visible-light image taken with ACS [top, right], because its light is stretched to invisible infrared wavelengths by the universe's expansion.

Astronomers used Hubble's Near Infrared Camera and Multi-Object Spectrometer (NICMOS) and NASA's Spitzer Space Telescope with its Infrared Array Camera (IRAC) — with help from the gravitational lensing cluster — to see the faraway galaxy.

The distant galaxy, dubbed A1689-zD1, appears as a grayish-white smudge in the close-up view taken with Hubble's NICMOS [center, right], and as a whitish blob in the Spitzer IRAC close-up view [bottom, right]. The galaxy is brimming with star birth. Hubble and Spitzer worked together to show that it is one of the youngest galaxies ever discovered. Astronomers estimate that the galaxy is 12.8 billion light-years away. Abell 1689 is 2.2 billion light-years away.

A1689-zD1 was born during the middle of the "dark ages," a period in the early universe when the first stars and galaxies were just beginning to burst to life. The dark ages lasted from about 400,000 to roughly a billion years after the Big Bang. Astronomers think that A1689-zD1 was one of the galaxies that helped end the dark ages.

The ACS images were taken in 2002, the NICMOS images in 2005 and 2007, and the Spitzer IRAC images in 2006.

Astronomers using NASA's Hubble Space Telescope have compiled a large catalog of gravitational lenses in the distant universe. The catalog contains 67 new gravitationally lensed galaxy images found around massive elliptical and lenticular-shaped galaxies. This sample demonstrates the rich diversity of strong gravitational lenses. If this sample is representative, there would be nearly half a million similar gravitational lenses over the whole sky.

The lenses come from a recently completed, large set of observations as part of a huge project to survey a single 1.6-square-degree field of sky (nine times the area of the full Moon) with several space-based and Earth-based observatories. The COSMOS project, led by Nick Scoville at the California Institute of Technology, used observations from several observatories including the Hubble Space Telescope, the Spitzer Space Telescope, the XMM-Newton spacecraft, the Chandra X-ray Observatory, the Very Large Telescope (VLT), the Subaru Telescope, and the Canada-France-Hawaii Telescope.

A team of European astronomers led by Jean-Paul Kneib (Laboratoire d'Astrophysique de Marseille) and Cecile Faure (Zentrum für Astronomie, University of Heidelberg) analyzed the results from Hubble's Advanced Camera for Surveys (ACS). From ACS high-resolution images, complemented by the extensive ground-based follow-up observations, astronomers have identified 67 strong gravitationally lensed galaxies. These lenses were found around very massive galaxies that are usually elliptical or lenticular in shape and have a deficiency of gas and dust.

The strong lensing produced by massive galaxies are much more common than the usual giant "arc" gravitationally lensed galaxies that Hubble has previously observed; but they are generally more difficult to find as they extend over a smaller area and have a wide variety of shapes.

Gravitational lensing occurs when light traveling toward us from a distant galaxy is magnified and distorted as it encounters a massive object between the galaxy and us. These gravitational lenses often allow astronomers to peer much farther back into the early universe than they would normally be able to do.

The massive objects that create the lenses are usually huge clusters of massive galaxies. "We typically see the gravitational lens create a series of bright arcs or spots around a galaxy cluster. What we are observing here is a similar effect but on a much smaller scale — happening only around a single but very massive galaxy," said Kneib.

Of the 67 gravitational lenses identified in the COSMOS survey, the most impressive lenses show the distorted and warped light of one or two background galaxies. At least four of the lenses produce Einstein rings, a complete circular image of a background galaxy, which is formed when the background galaxy, a massive, foreground galaxy, and the Hubble Space Telescope are all aligned perfectly.

Hubble astronomers went through a unique process to identify these incredible natural lenses. First, possible galaxies were identified from a galaxy catalog, comprising more than 2 million galaxies. "We then had to look through each individual COSMOS image by eye and identify any potential strong gravitational lenses," said Faure. Finally, checks were made to see if the foreground galaxy and the lensed galaxy were really different or just one galaxy with an odd shape. "With this sample of gravitational systems identified by the human eye, we now plan to use the sample of lenses to train robot software to find more of these lenses across the entire Hubble image archive, and we may find even more strong lensing systems in the COSMOS field," added Kneib.

The new results confirm that the universe is filled with gravitational lensing systems. Extrapolating these new findings to the whole sky predicts no less than half a million similar lenses in total.

The study of these gravitational lenses will give astronomers a first-rate opportunity to probe the dark matter distribution around galactic lenses. Once astronomers find even larger numbers of these smaller, stronger lenses, they can be used to create a census of galaxy masses in the universe to test the predictions of cosmological models.

The research team consists of Cecile Faure (Zentrum Für Astronomie Heidelberg), Jean-Paul Kneib (Laboratoire d'Astrophysique de Marseille & the California Institute of Technology), Giovanni Covone (Laboratoire d'Astrophysique de Marseille & INAF, Osservatorio Astronomico di Capodimonte), Lidia Tasca (Laboratoire d'Astrophysique de Marseille), Alexie Leauthaud (Laboratoire d'Astrophysique de Marseille), Peter Capak (California Institute of Technology), Knud Jahnke (Max-Planck-Institut für Astronomie), Vernesa Smolcic (Max-Planck-Institut für Astronomie), Sylvain de la Torre (Laboratoire d'Astrophysique de Marseille), Richard Ellis (California Institute of Technology), Alexis Finoguenov (Max-Planck-Institut für extraterrestrische Physik), Catherine Heymans (Department of Physics & Astronomy, University of British Columbia), Anton Koekemoer (Space Telescope Science Institute), Oliver Le Fevre (Laboratoire d'Astrophysique de Marseille), Richard Massey (California Institute of Technology), Yannick Mellier (Institut d'Astrophysique de Paris), Alexandre Refregier (Service d'Astrophysique, CEA/Saclay), Jason Rhodes (California Institute of Technology), Nick Scoville (California Institute of Technology), Eva Schinnerer (Max-Planck-Institut für Astronomie), James Taylor (California Institute of Technology & Department of Physics and Astronomy, University of Waterloo), Ludovic Van Waerbeke (Department of Physics & Astronomy, University of British Columbia), and Jakob Walcher (Laboratoire d'Astrophysique de Marseille).

For more information, please contact:

Cecile Faure
Zentrum Für Astronomie, University of Heidelberg, Germany
011-49-1-762-1901-669
cfaure@ari.uni-heidelberg.de

Jean-Paul Kneib
Laboratoire d'Astrophysique de Marseille, France
011-33-4-91-05-59-13
jean-paul.kneib@oamp.fr

Nick Scoville
California Institute of Technology, Pasadena, Calif.
626-395-4979
nzs@astro.caltech.edu

Peter Capak
California Institute of Technology, Pasadena, Calif.
626-395-6422
capak@astro.caltech.edu

Ray Villard
Space Telescope Science Institute, Baltimore, Md.
410-338-4514
villard@stsci.edu

Lars Lindberg Christensen
Hubble/ESA, Garching, Germany
011-49-89-3200-6306
lars@eso.org

Probing a glowing bubble of gas and dust encircling a dying star, NASA's Hubble Space Telescope reveals a wealth of previously unseen structures.

The object, called NGC 2371, is a planetary nebula, the glowing remains of a Sun-like star. The remnant star visible at the center of NGC 2371 is the super-hot core of the former red giant, now stripped of its outer layers. Its surface temperature is a scorching 240,000 degrees Fahrenheit. NGC 2371 lies about 4,300 light-years away in the constellation Gemini.

The Hubble image reveals several remarkable features, most notably the prominent pink clouds lying on opposite sides of the central star. This color indicates that they are relatively cool and dense, compared to the rest of the gas in the nebula.

Also striking are the numerous, very small pink dots, marking relatively dense and small knots of gas, which also lie on diametrically opposite sides of the star. These features appear to represent the ejection of gas from the star along a specific direction. The jet's direction has changed with time over the past few thousand years. The reason for this behavior is not well understood, but might be related to the possible presence of a second star orbiting the visible central star.

A planetary nebula is an expanding cloud of gas ejected from a star that is nearing the end of its life. The nebula glows because of ultraviolet radiation from the hot remnant star at its center. In only a few thousand years the nebula will dissipate into space. The central star will then gradually cool down, eventually becoming a white dwarf, the final stage of evolution for nearly all stars.

The Hubble picture of NGC 2371 is a false-color image, prepared from exposures taken through filters that detect light from sulfur and nitrogen (red), hydrogen (green), and oxygen (blue). These images were taken with Hubble's Wide Field Planetary Camera 2 in November 2007, as part of the Hubble Heritage program.

For additional information, contact:

Ray Villard
Space Telescope Science Institute, Baltimore, Md.
410-338-4514
villard@stsci.edu

Keith Noll/Howard Bond
Space Telescope Science Institute, Baltimore, Md.
410-338-1828/4718
noll@stsci.edu/bond@stsci.edu

The core of the spectacular globular cluster Omega Centauri glitters with the combined light of 2 million stars. The entire cluster contains 10 million stars, and is among the biggest and most massive of some 200 globular clusters orbiting the Milky Way Galaxy. Omega Centauri lies 17,000 light-years from Earth.

Astronomers Eva Noyola, of the Max-Planck Institute of Extraterrestrial Physics in Garching, Germany, and Karl Gebhardt of the University of Texas at Austin, have reported on the possible detection of an intermediate-mass black hole in the core of Omega Centauri.

The result is primarily based on spectroscopic measurements obtained with the Gemini South observatory in Chile which suggest the stars are moving around the central core of the cluster at higher than expected velocities.

Among the possible explanations for these speedy stars — and the one favored by their study — is that an intermediate-mass black hole of approximately 40,000 solar masses resides at the center of Omega Centauri. Its powerful gravitational field speeds up the motions of stars near the core.

Astronomers have speculated for years that some globular clusters may harbor in their centers medium-size, or intermediate-mass, black holes with masses of some tens of thousands of suns. Medium-size black holes are much less massive than the supermassive black holes, which are up to billions of solar masses and reside in the centers of large galaxies.

Hubble images taken with the Advanced Camera for Surveys were used in key areas in support of this study: to help pinpoint the center of the cluster, as well as to measure the amount of starlight at the cluster center.

Using the European Southern Observatory's Very Large Telescope in Paranal, Chile, Noyola and Gebhardt are planning to obtain follow-up observations to help confirm the existence of an intermediate-mass black hole.

The Hubble images were taken in June 2002.

These images taken by NASA's Hubble Space Telescope show nine compact, ultradense galaxies as they appeared 11 billion years ago.

The galaxies are only 5,000 light-years across and yet are 200 billion times more massive than the Sun. They are a fraction of the size of today's grownup galaxies but contain the same number of stars. Each galaxy could fit inside the central hub of our Milky Way Galaxy.

Hubble's Near Infrared Camera and Multi-Object Spectrometer snapped these images between June 2006 and June 2007.

Astronomy textbooks typically present galaxies as staid, solitary, and majestic island worlds of glittering stars.

But galaxies have a dynamical side. They have close encounters that sometimes end in grand mergers and overflowing sites of new star birth as the colliding galaxies morph into wondrous new shapes.

Today, in celebration of the Hubble Space Telescope's 18th launch anniversary, 59 views of colliding galaxies constitute the largest collection of Hubble images ever released to the public. This new Hubble atlas dramatically illustrates how galaxy collisions produce a remarkable variety of intricate structures in never-before-seen detail.

Astronomers estimate that only one out of one thousand galaxies in the nearby universe in the act of colliding. However, galaxy mergers were much more common long ago when they were closer together, because the expanding universe was smaller. Astronomers study how gravity choreographs their motions in the game of celestial bumper cars and try to observe them in action.

For all their violence, galactic smash-ups take place at a glacial rate by human standards - timescales on the order of several hundred million years. The images in the Hubble atlas capture snapshots of the various merging galaxies at various stages in their collision.

Most of the 59 new Hubble images are part of a large investigation of luminous and ultra- luminous infrared galaxies called the GOALS project (Great Observatories All-sky LIRG Survey). This survey combines observations from Hubble, NASA's Spitzer Space Telescope, NASA's Chandra X-ray Observatory, and NASA's Galaxy Evolution Explorer. The majority of the Hubble observations are led by Aaron S. Evans of the University of Virginia, Charlottesville, the National Radio Astronomy Observatory, and Stony Brook University.

For more information, contact:

Ray Villard
Space Telescope Science Institute, Baltimore, Md.
410-338-4514
villard@stsci.edu

Lars Lindberg Christensen
Hubble/ESA, Garching, Germany
011-49-89-3200-6306
lars@eso.org

Aaron Evans
University of Virginia, Charlottesville, Va.
ae3f@mail.astro.virginia.edu

Arp 148 is the staggering aftermath of an encounter between two galaxies, resulting in a ring-shaped galaxy and a long-tailed companion. The collision between the two parent galaxies produced a shockwave effect that first drew matter into the center and then caused it to propagate outwards in a ring. The elongated companion perpendicular to the ring suggests that Arp 148 is a unique snapshot of an ongoing collision. Infrared observations reveal a strong obscuration region that appears as a dark dust lane across the nucleus in optical light. Arp 148 is nicknamed Mayall s object and is located in the constellation of Ursa Major, the Great Bear, approximately 500 million light-years away. This interacting pair of galaxies is included in Arp's catalog of peculiar galaxies as number 148.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

UGC 9618, also known as VV 340 or Arp 302 consists of a pair of very gas-rich spiral galaxies in their early stages of interaction: VV 340A is seen edge-on to the left, and VV 340B face-on to the right. An enormous amount of infrared light is radiated by the gas from massive stars that are forming at a rate similar to the most vigorous giant star-forming regions in our own Milky Way. UGC 9618 is 450 million light-years away from Earth, and is the 302nd galaxy in Arp's Atlas of Peculiar Galaxies.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

Arp 256 is a stunning system of two spiral galaxies in an early stage of merging. The Hubble image displays two galaxies with strongly disrupted shapes and an astonishing number of blue knots of star formation that look like exploding fireworks. The galaxy to the left has two extended ribbon-like tails of gas, dust and stars. The system is a luminous infrared system radiating more than a hundred billion times the luminosity of our Sun. Arp 256 is located in the constellation of Cetus, the Whale, about 350 million light-years away. It is the 256th galaxy in Arp's Atlas of Peculiar Galaxies.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

NGC 6670 is a gorgeous pair of overlapping edge-on galaxies resembling a leaping dolphin. Scientists believe that NGC 6670 has already experienced at least one close encounter and is now in the early stages of a second. The nuclei of the two galaxies are approximately 50,000 light-years apart. NGC 6670 glows in the infrared with more than a hundred billion times the luminosity of our Sun and is thought to be entering a starburst phase. The pair is located some 400 million light-years away from Earth.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

NGC 6240 is a peculiar, butterfly- or lobster-shaped galaxy consisting of two smaller merging galaxies. It lies in the constellation of Ophiuchus, the Serpent Holder, some 400 million light-years away. Observations with NASA s Chandra X-ray Observatory have disclosed two giant black holes, about 3,000 light-years apart, which will drift toward one another and eventually merge together into a larger black hole. The merging process, which began about 30 million years ago, triggered dramatic star formation and sparked numerous supernova explosions. The merger will be complete in some tens to hundreds of millions of years.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

ESO 593-8 is an impressive pair of interacting galaxies with a feather-like galaxy crossing a companion galaxy. The two components will probably merge to form a single galaxy in the future. The pair is adorned with a number of bright blue star clusters. ESO 593-8 is located in the constellation of Sagittarius, the Archer, some 650 million light-years away from Earth.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

NGC 454 is galaxy pair comprising a large red elliptical galaxy and an irregular gas-rich blue galaxy. The system is in the early stages of an interaction that has severely distorted both components. The three bright blue knots of very young stars to the right of the two main components are probably part of the irregular blue galaxy. Although the dust lanes that stretch all the way to the center of the elliptical galaxy suggest that gas has penetrated that far, no signs of star formation or nuclear activity are visible. The pair is approximately 164 million light-years away.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

UGC 8335 is a strongly interacting pair of spiral galaxies resembling two ice skaters. The interaction has united the galaxies via a bridge of material and has yanked two strongly curved tails of gas and stars from the outer parts of their bodies . Both galaxies show dust lanes in their centers. UGC 8335 is located in the constellation of Ursa Major, the Great Bear, about 400 million light-years from Earth. It is the 238th galaxy in Arp's Atlas of Peculiar Galaxies.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

This Hubble image displays a beautiful pair of interacting spiral galaxies with swirling arms. The smaller of the two, dubbed LEDA 62867 and positioned to the left of the frame, seems to be safe for now, but will probably be swallowed by the larger spiral galaxy, NGC 6786 (to the right) eventually. There is already some disturbance visible in both components. The pair is number 538 in Karachentsev's Catalog of Pairs of Galaxies. A supernova was seen to explode in the large spiral in 2004. NGC 6786 is located in the constellation of Draco, the Dragon, about 350 million light-years away.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

This galaxy features a single nucleus, containing a blue central disk with delicate fine structure in the outer parts, and tidal tails indicative of two former disk galaxies. At present these galaxies appear to have completed their merger. The remnant shows clear signs that the merger was gas-rich and accompanied by a starburst. NGC 17 is gas-rich and can sustain its strong central starburst and present mild central activity for some time to come. NGC 17 is located about 250 million light-years away in the constellation of Cetus, the Whale.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

This Hubble image of ESO 77-14 is a stunning snapshot of a celestial dance performed by a pair of similar sized galaxies. Two clear signatures of the gravitational tug of war between the galaxies are the bridge of material that connects them and the disruption of their main bodies. The galaxy on the right has a long, bluish arm while its companion has a shorter, redder arm. This interacting pair is in the constellation of Indus, the Indian, some 550 million light-years away from Earth. The dust lanes between the two galaxy centers show the extent of the distortion to the originally flat disks that have been pulled into three-dimensional shapes.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

NGC 6050/IC 1179 (Arp 272) is a remarkable collision between two spiral galaxies, NGC 6050 and IC 1179, and is part of the Hercules Galaxy Cluster, located in the constellation of Hercules. The galaxy cluster is part of the Great Wall of clusters and superclusters, the largest known structure in the universe. The two spiral galaxies are linked by their swirling arms. Arp 272 is located some 450 million light-years away from Earth and is the number 272 in Arp's Atlas of Peculiar Galaxies.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

2MASX J09133888-1019196 comprises two interacting galaxies that are both disturbed by gravitational interaction. The wide separation of the pair - approximately 130,000 light-years - suggests that the galaxies are just beginning to merge. Together the two galaxies form an ultra-luminous infrared system, which is unusual for the early stages of an interaction. One possible explanation is that the one or both of the components have already experienced a merger or interaction. Giant black holes lurk at the cores of both galaxies, which are found in the constellation of Hydra, the Sea Serpent, about 700 million light-years away from Earth.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

AM 0500-620 consists of a highly symmetric spiral galaxy seen nearly face-on and partially backlit by a background galaxy. The foreground spiral galaxy has a number of dust lanes between its arms. The background galaxy was earlier classified as an elliptical galaxy, but Hubble has now revealed a galaxy with dusty spiral arms and bright knots of stars. AM0500-620 is 350 million light-years away from Earth in the constellation of Dorado, the Swordfish.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

AM 0702 consists of a couple of detached galaxies, far apart and probably only just beginning to interact. The first signs of the interaction are visible in the galaxy on the left, where the outer structure of the spiral arms is starting to expand, extending a tidal tail of matter out into space.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

AM 1316-241 is made up of two interacting galaxies - a spiral galaxy (on the left of the frame) in front of an elliptical galaxy (on the right of the frame). The starlight from the background galaxy is partially obscured by the bands and filaments of dust associated with the foreground spiral galaxy. The Hubble image unravels the fine detail in the patchy clumps of dust confined to the spiral arms of the spiral galaxy. This dust reddens the light from the background just as the intervening dust in the Earth's atmosphere reddens sunsets here. AM1316-241 is located some 400 million light-years away toward the constellation of Hydra, the Water Snake.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

Arp 220 appears to be a single, odd-looking galaxy, but is in fact a nearby example of the aftermath of a collision between two spiral galaxies. It is the brightest of the three galactic mergers closest to Earth, about 250 million light-years away in the constellation of Serpens, the Serpent. The collision, which began about 700 million years ago, has sparked a cracking burst of star formation, resulting in about 200 huge star clusters in a packed, dusty region about 5,000 light-years across (about 5 percent of the Milky Way's diameter). The amount of gas in this tiny region equals the amount of gas in the entire Milky Way Galaxy. The star clusters are the bluish-white bright knots visible in the Hubble image. Arp 220 glows brightest in infrared light and is an ultra-luminous infrared galaxy. Previous Hubble observations, taken in the infrared at a wavelength that looks through the dust, have uncovered the cores of the parent galaxies 1,200 light-years apart. Observations with NASA s Chandra X-ray Observatory have also revealed X-rays coming from both cores, indicating the presence of two supermassive black holes. Arp 220 is the 220th galaxy in Arp's Atlas of Peculiar Galaxies.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

CGCG 436-030, the eye-catching spiral galaxy in the image, shows a very pronounced curling tail. The companion galaxy, located to the bottom-right of the image, displays an intricate structure, including a number of trails that extend quite far out from its core. The bright star that appears between the two galaxies does not belong to the interacting system and is located within the Milky Way. CGCG 436-030 is located in the constellation of Pisces, the Fish, about 400 million light-years away.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

The galaxies of this beautiful interacting pair bear some resemblance to musical notes on a stave. Long tidal tails sweep out from the two galaxies: gas and stars were stripped out and torn away from the outer regions of the galaxies. The presence of these tails is the unique signature of an interaction. ESO 69-6 is located in the constellation of Triangulum Australe, the Southern Triangle, about 650 million light-years away from Earth.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

ESO 99-4 is a galaxy with a highly peculiar shape that is probably the remnant of an earlier merger process that has deformed it beyond visual recognition, leaving the main body largely obscured by dark bands of dust. ESO 99-4 lies in a rich field of foreground stars, in the constellation of Triangulum Australe, the Southern Triangle, about 400 million light-years away.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

ESO 148-2 is a beautiful object that resembles an owl in flight. It consists of a pair of former disk galaxies undergoing a collision. The cores of the two individual galaxies - seen at the center of the image - are embedded in hot dust and contain a large number of stars. Two huge wings sweep out from the center and curve in opposite directions. These are tidal tails of stars and gas that have been pulled from the easily distorted disks of the galaxies. This cosmic owl is one of the most luminous infrared galaxies known and is located some 600 million light-years away from Earth.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

ESO 239-2 is most likely the result of a cosmic collision or a lengthy merger process that will eventually result in an elliptical galaxy. The messy intermediate stage, captured here, is a galaxy with long, tangled tidal tails that envelope the galaxy's core.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

ESO 255-7 consists of a quartet of interacting galaxies. Three or four galaxies are embedded in a common structure with an arc-like shape. The upper part of this structure appears almost like one single galaxy but has in fact two component galaxies. The lowest galaxy is substantially obscured by dust. The interacting group is about 550 million light-years away from Earth, in the constellation of Puppis, the Stern.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

ESO 286-19 is a peculiar galaxy that consists of what were originally two disk galaxies that are now in the midst of an ongoing collision. It has undergone a burst of star formation that ended about eight million years ago. ESO 286-19 has a long tail to the right of the main body, and a shorter tail curving to the left. The presence of the tails is a unique signature of the merger process: gas and stars were stripped out by rippling gravitational pulls as the galaxies collided and the outer regions of the parent galaxies were torn off. These tidal tails can persist long after the galaxies have finally merged. ESO 286-19 is located 600 million light-years away from Earth and is an exceptionally luminous source of infrared radiation.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

ESO 507-70 is an odd-looking galaxy that is probably the remnant of an earlier merger process. It is a chaotic swirl of gas, dust and stars with no sign of the conjectured original spiral or elliptical structure, now lost and distorted beyond recognition in a gravitational encounter with another galaxy. ESO 507-70 is some 300 million light-years away from Earth toward the constellation of Hydra, the Water Snake.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

ESO 550-2 shows a pair of spiral galaxies, the larger nearly face-on and accompanied by a smaller, highly tilted partner. Tidal interaction from the smaller companion has clearly deformed one arm of the larger galaxy. Strong star formation continues both in the deformed arm and in a ring structure around the galaxy's core. The pair is surrounded by the glow of faintly shining stars and interstellar matter that has been smeared through space by the gravitational effects of the collision and the pull of a third nearby galaxy.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

Astronomy textbooks typically present galaxies as staid, solitary, and majestic island worlds of glittering stars. But galaxies have a dynamical side. They have close encounters that sometimes end in grand mergers and overflowing sites of new star birth as the colliding galaxies morph into wondrous new shapes. Today, in celebration of the Hubble Space Telescope's 18th launch anniversary, this poster with 59 views of colliding galaxies constitute the largest collection of Hubble images ever released to the public. This new Hubble atlas dramatically illustrates how galaxy collisions produce a remarkable variety of intricate structures in never-before-seen detail.

IC 883 displays a very disturbed, complex central region with two tidal tails of approximately the same length emerging at nearly right angles: one diagonally to the top right of the frame and the other to the bottom right. The twin tidal tails suggest that IC 883 is the remnant of the merger of two gas-rich disk galaxies. The collision appears to have triggered a burst of star formation, indicated by a number of bright star clusters in the central region. IC 883 is 300 million light-years away toward the constellation of Canes Venatici, the Hunting Dogs. It is Number 193 in Arp's Atlas of Peculiar Galaxies.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

IC 1623 is an interacting galaxy system that is very bright when observed in the infrared. One of the two galaxies, the infrared-bright, but optically obscured galaxy VV 114E, has a substantial amount of warm and dense gas. Warm and dense gas is also found in the overlap region connecting the two nuclei. Observations further support the notion that IC 1623 is approaching the final stage of its merger, when a violent central inflow of gas will trigger intense starburst activity that could boost the infrared luminosity above the ultra-luminous threshold. The system will likely evolve into a compact starburst system similar to Arp 220. IC 1623 is located about 300 million light-years away from Earth.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

IC 2545 is a beautiful, but deceptive object that appears to be a single S-shaped galaxy, but is actually a pair of merging galaxies. The two cores of the parent galaxies are still visible in the central region. Other telltale markers for the collision include two pronounced tidal arms of gas and stars flung out from the central region. The tidal arm curving upwards and clockwise in the image contains a number of blue star clusters. IC 2545 glows strongly in the infrared part of the spectrum - another sign that it is a pair of merging galaxies. It lies in the constellation of Antlia, the Air Pump, some 450 million light-years away from Earth.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

IC 2810 is a disk galaxy viewed nearly edge-on. It is slightly disturbed by gravitational interaction with a smaller, dusty companion (located to the bottom of the image). The larger galaxy shows blue knots of star formation. Although the pair has no overlapping region at present, it is possible that the two will eventually collide in the future. IC 2810 is located in the constellation of Leo, the Lion, about 450 million light-years away.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

IC 4687 forms a triplet with two other galaxies: IC 4686 to the right and IC 4689 further to the right. IC 4687 has a chaotic body of stars, gas and dust and a large curly tail to the left. The two companions are partially obscured by dark bands of dust. The interacting triplet is about 250 million light-years away from Earth, in the constellation of Pavo, the Peacock.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

IC 5298 is a beautiful face-on spiral galaxy with two long arms extending from the central bulge and curving back amongst the scattered stars, gas and dust. A nearby smaller companion is linked by a bridge of matter to the principal galaxy in an interaction reminiscent of the famous Whirlpool Galaxy, M51. There is also a third faint, irregular galaxy, visible at the top of the image that is also linked by a bridge of matter and probably involved in the interaction.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

This is a system of merging galaxies with a bizarre shape. Powerful young starburst regions hang as long threadlike structures between the main galaxy cores. The system almost qualifies as an ultra-luminous system, but has not yet reached the late stage of coalescence that is the norm for most ultra-luminous systems. II Zw 96 is located in the constellation of Delphinus, the Dolphin, about 500 million light-years away from Earth.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

This system consists of two interacting spiral galaxies. The galaxy to the left displays a dim plume of luminosity that extends to the right in the direction of the second spiral. Both galaxies are partly obscured by dust lanes. The galaxy at center is adorned with blue knots of stars. IRAS 18090+0130 is located in the constellation of Ophiuchus, the Serpent Holder, some 400 million light-years away from Earth.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

IRAS 20351+2521 is a galaxy with a sprawling structure of gas, dust and numerous blue star knots. IRAS 20351+2521 is located in the constellation of Vulpecula, the Fox, 450 million light-years away from Earth.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

This system is an interacting galaxy pair. The interaction has disturbed both galaxies: the lower galaxy has a bizarre structure and a tidal tail emerges from the main body of the upper galaxy. The galaxy pair lies in a crowded field of Milky Way stars. IRAS 21101+5810 is located in the constellation of Cepheus, the King, about 550 million light-years away from Earth.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

IRAS F10565+2448 is a system that appears to consist of two colliding galaxies. The larger galaxy has dust lanes, while the smaller galaxy has a pronounced curved tail that has been pulled away from the center (downwards as seen here). IRAS F10565+2448 is located in the constellation of Leo, the Lion, about 600 million light-years away. Some scientists regard this system as a candidate for a three-galaxy system. The nature of the third object is unknown.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

MCG+08-11-002 is an odd-looking galaxy with a spectacular dark band of absorbing dust in front of the galaxy's center, making it resemble a "Black Eye". Scientists believe that it is the remnant of an earlier collision of two separate galaxies. This peculiar galaxy is at the center of a rich field of foreground stars, close to the plane of our own Milky Way galaxy. MCG+08-11-002 is about 250 million light-years away in the constellation of Auriga, the Charioteer.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

MCG+12-02-001 consists of a pair of galaxies visibly affected by gravitational interaction as material is flung out in opposite directions. A large galaxy can be seen at the top of the frame and a smaller galaxy resembling an erupting volcano is at the bottom. The bright core of this galaxy emerges from the tip of the volcano . MCG+12-02-001 is a luminous infrared system that radiates with more than a hundred billion times the luminosity of our Sun. It is located some 200 million light-years away from Earth toward the constellation of Cassiopeia, the Seated Queen.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

Markarian 273 is a galaxy with a bizarre structure that somewhat resembles a toothbrush. The Hubble image shows an intricate central region and a striking tail that extends diagonally towards the bottom-right of the image. The tail is about 130 thousand light-years long and is strongly indicative of a merger between two galaxies. Markarian 273 has an intense region of starburst, where 60 solar masses of new stars are born each year. Near-infrared observations reveal a nucleus with two components. Markarian 273 is one of the most luminous galaxies when observed in the infrared, and is located 500 million light-years away from Earth.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

NGC 520 is the product of a collision between two disk galaxies that started 300 million years ago. It exemplifies the middle stages of the merging process: the disks of the parent galaxies have merged together, but the nuclei have not yet coalesced. It features an odd-looking tail of stars and a prominent dust lane that runs diagonally across the center of the image and obscures the galaxy. NGC 520 is one of the brightest galaxy pairs on the sky, and can be observed with a small telescope toward the constellation of Pisces, the Fish, having the appearance of a comet. It is about 100 million light-years away and about 100,000 light-years across. The galaxy pair is included in Arp's catalog of peculiar galaxies as Arp 157.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

NGC 695 is a peculiar galaxy which looks like a revolving tornado. It is a disturbed spiral galaxy, seen face-on, with loosely wound spiral arms. Knotty star-forming regions are tangled in a mesh of dust and gas. NGC 695 is in an interaction with a small companion located just outside the image to the left. Scientists believe that this is a recent but relatively weak interaction. NGC 695 is located in the constellation of Aries, the Ram, about 450 million light-years away from Earth.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

The galaxy system NGC 1614 has a bright optical center and two clear inner spiral arms that are fairly symmetrical. It also has a spectacular outer structure that consists principally of a large one-sided curved extension of one of these arms to the lower right, and a long, almost straight tail that emerges from the nucleus and crosses the extended arm to the upper right. The galaxy appears to be the result of a tidal interaction and the resulting merger of two predecessor systems. The system has a nuclear region of quasar-like luminosity, but shows no direct evidence for an active nucleus. It is heavily and unevenly reddened across its nucleus, while infrared imaging also shows a ridge of dust. The linear tail to the upper right and extended arms to the lower right are likely the remains of an interacting companion and the tidal plume(s) caused by the collision. NGC 1614 is located about 200 million light-years away from Earth in the constellation of Eridanus, the River.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

NGC 3256 is an impressive example of a peculiar galaxy that is actually the relict of a collision of two separate galaxies that took place in a distant past. The telltale signs of the collision are two extended luminous tails swirling out from the galaxy. NGC 3256 belongs to the Hydra-Centaurus supercluster complex and provides a nearby template for studying the properties of young star clusters in tidal tails. The system hides a double nucleus and a tangle of dust lanes in the central region. The tails are studded with a particularly high density of star clusters.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

This system consists of a pair of galaxies, dubbed NGC 3690 (or Arp 299), which made a close pass some 700 million years ago. As a result of this interaction, the system underwent a fierce burst of star formation. In the last fifteen years or so six supernovae have popped off in the outer reaches of the galaxy, making this system a distinguished supernova factory. Arp 299 belongs to the family of ultra-luminous infrared galaxies and is located in the constellation of Ursa Major, the Great Bear, approximately 150 million light-years away. It is the 299th galaxy in Arp's Atlas of Peculiar Galaxies. Despite its enormous amount of absorbing dust, enough violet and near-ultraviolet light leaks out for it to be number 171 in B.E. Markarian's catalog of galaxies with excess ultraviolet emission.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

NGC 5256, also known as Markarian 266, is a striking example of two disk galaxies that are about to merge. Spectacular streamers of gas surround the two nuclei and eye-catching blue spiral trails indicate recent star formation. The shape of the object is highly disturbed and observations in various wavelength regimes — infrared, millimeter-wave and radio — provide additional evidence for a starburst in this system. NGC 5256 is located in the constellation of Ursa Major, the Great Bear, some 350 million light-years from Earth. Each galaxy also contains an active galactic nucleus, evidence that the chaos is allowing gas to fall into the regions around central black holes as well as feeding starbursts. Recent observations from the Chandra X-ray Observatory show that both nuclei, as well as a region of hot gas in between them, have been heated by the shock waves driven as gas clouds at high velocities collide.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

NGC 5257/8 (Arp 240) is an astonishing galaxy pair, composed of spiral galaxies of similar mass and size, NGC 5257 and NGC 5258. The galaxies are visibly interacting with each other via a bridge of dim stars connecting the two galaxies, almost like two dancers holding hands while performing a pirouette. Both galaxies harbor supermassive black holes in their centers and are actively forming new stars in their disks. Arp 240 is located in the constellation Virgo, approximately 300 million light-years away, and is the 240th galaxy in Arp's Atlas of Peculiar Galaxies. With the exception of a few foreground stars from our own Milky Way all the objects in this image are galaxies.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

NGC 5331 is a pair of interacting galaxies beginning to hold their arms . There is a blue trail which appears in the image flowing to the right of the system. NGC 5331 is very bright in the infrared, with about a hundred billion times the luminosity of the Sun. It is located in the constellation Virgo, the Maiden, about 450 million light-years away from Earth.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

This beautiful pair of interacting galaxies consists of NGC 5754, the large spiral on the right, and NGC 5752, the smaller companion in the bottom left corner of the image. NGC 5754's internal structure has hardly been disturbed by the interaction. The outer structure does exhibit tidal features, as does the symmetry of the inner spiral pattern and the kinked arms just beyond its inner ring. In contrast, NGC 5752 has undergone a starburst episode, with a rich population of massive and luminous star clusters clumping around the core and intertwined with intricate dust lanes. The contrasting reactions of the two galaxies to their interaction are due to their differing masses and sizes. NGC 5754 is located in the constellation Bootes, the Herdsman, some 200 million light-years away.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

NGC 6090 is a beautiful pair of spiral galaxies with an overlapping central region and two long tidal tails formed from material ripped out of the galaxies by gravitational interaction. The two visible cores are approximately 10,000 light-years apart, suggesting that the two galaxies are at an intermediate stage in the merging process. The Hubble image reveals bright knots of newborn stars in the region where the two galaxies overlap. The right hand component has a clear spiral structure if viewed face-on, while the other is seen edge-on with no spiral arms visible. NGC 6090 is located in the constellation of Draco, the Dragon, about 400 million light-years away from Earth. A number of fainter, and more distant, background galaxies is seen in the image. This system has much in common with the famous Antennae galaxies both in terms of how far the merger has progressed and in our viewing angle.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

NGC 6621/2 (VV 247, Arp 81) is a strongly interacting pair of galaxies, seen about 100 million years after their closest approach. It consists of NGC 6621 (to the left) and NGC 6622 (to the right). NGC 6621 is the larger of the two, and is a very disturbed spiral galaxy. The encounter has pulled a long tail out of NGC 6621 that has now wrapped behind its body. The collision has also triggered extensive star formation between the two galaxies. Scientists believe that Arp 81 has a richer collection of young massive star clusters than the notable Antennae galaxies (which are much closer than Arp 81). The pair is located in the constellation of Draco, approximately 300 million light-years away from Earth. Arp 81 is the 81st galaxy in Arp's Atlas of Peculiar Galaxies.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

This is a stunning pair of interacting galaxies, the barred spiral Seyfert 1 galaxy NGC 7469 (Arp 298, Mrk 1514), a luminous infrared source with a powerful starburst deeply embedded into its circumnuclear region, and its smaller companion IC 5283. This system is located about 200 million light-years away from Earth in the constellation of Pegasus, the Winged Horse.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

NGC 7674 (seen just above the center), also known as Markarian 533, is the brightest and largest member of the so-called Hickson 96 compact group of galaxies, consisting of four galaxies. This stunning Hubble image shows a spiral galaxy nearly face-on. The central bar-shaped structure is made up of stars. The shape of NGC 7674, including the long narrow streamers seen to the left of and below the galaxy can be accounted for by tidal interactions with its companions. NGC 7674 has a powerful active nucleus of the kind known as a type 2 Seyfert that is perhaps fed by gas drawn into the center through the interactions with the companions. NGC 7674 falls into the family of luminous infrared galaxies and is featured in Arp's Atlas of Peculiar Galaxies as number 182. It is located in the constellation of Pegasus, the Winged Horse, about 400 million light-years away from Earth.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

UGC 4881, known as the "The Grasshopper," is a stunning system consisting of two colliding galaxies. It has a bright curly tail containing a remarkable number of star clusters. The galaxies are thought to be halfway through a merger the cores of the parent galaxies are still clearly separated, but their disks are overlapping. A supernova exploded in this system in 1999 and astronomers believe that a vigorous burst of star formation may have just started. This notable object is located in the constellation of Lynx, some 500 million light-years away from Earth. UGC 4881 is the 55th galaxy in Arp's Atlas of Peculiar Galaxies.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

UGC 5101 is a peculiar galaxy with a single nucleus contained within an unstructured main body that suggests a recent interaction and merger. UGC 5101 is thought to contain an active galactic nucleus an extremely bright, compact core - buried deep in the gas and dust. A pronounced tail extends diagonally to the top-right of the frame. A fainter halo of stars surrounds the galaxy and is visible in the image, due to Hubble s ability to collect and detect faint light. This halo is probably a result of the earlier collision. UGC 5101 is about 550 million light-years away from Earth.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

The extraordinary galaxy UGC 8058, also known as Markarian 231, was discovered in 1969 as part of a survey searching for galaxies with strong ultraviolet radiation. It has long tidal tails and a disturbed shape. Results from the first spectrum showed clear signs of the presence of a powerful quasar in the center that made Markarian 231 unique in the Markarian sample. Markarian 231 has maintained its reputation as an exceptional object since those early observations and continues to be a favorite target in all wavelength regimes. Its infrared luminosity is similar to that of quasars, making it one of the most luminous and powerful known ultra-luminous infrared galaxies. Although the emission of many ultra-luminous infrared galaxies appears to be dominated by energetic starbursts, Markarian 231 has been repeatedly identified as an exception and many pieces of evidence point toward an accreting black hole as the major power source behind the enormous infrared luminosity. Although the primary power source behind the incredible far-infrared luminosity of Markarian 231 is almost certainly an active nucleus, the galaxy is also undergoing an energetic starburst. Most dramatically a nuclear ring of active star formation with a rate estimated to be greater than 100 solar masses per year has been found in the center. UGC 8058 is located about 600 million light-years away from Earth.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

UGC 12812, also known as Markarian 331, is a spiral galaxy with no obvious tidal tails. It is located in the lower part of the Hubble image. Two neighboring blue galaxies are seen at the top of the frame. The galaxy at the very top is embellished by a remarkable number of blue star knots. Observations point to the presence of a giant black hole anchored at the center of the bright core of UGC 12812. The galaxy produces 80 solar masses of new stars on average every year. It is an open question whether Markarian 331 is actually a merging system or whether its infrared brightness stems from another process. UGC 12812 is located in the constellation of Pegasus, the Winged Horse, about 250 million light-years away from Earth.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

VV 283 looks like a single peculiar galaxy, but is in fact a pair of merging galaxies. A tidal tail swirls out from a messy central region and splits into two branches. The upward twisting branch is brightened by luminous blue star knots. Like many merging systems, VV 283 is a very luminous infrared system, radiating nearly one thousand billion times energy more than our Sun. VV 283 is located in the constellation of Virgo, the Maiden, some 500 million light-years away.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

VV 705, or Markarian 848, consists of two galaxies that seem to be embracing each other. Two long, highly curved arms of gas and stars emerge from a central region with two cores. One arm, curving clockwise, stretches to the top of the image where it makes a U-turn and interlocks with the other arm that curves up counter-clockwise from below. The two cores are 16,000 light-years apart. The pair is thought to be midway through a merger. Markarian 848 is located in the constellation of Bootes, the Bear Watcher, and is approximately 550 million light-years away from Earth.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

Peering across 7.5 billion light-years and halfway back to the Big Bang, NASA's Hubble Space Telescope has photographed the fading optical counterpart of a powerful gamma ray burst that holds the record for being the intrinsically brightest naked-eye object ever seen from Earth. For nearly a minute this single star was as bright as 10 million galaxies. Hubble Wide Field and Planetary Camera 2 (WFPC2) images of GRB 080319B, taken on Monday, April 7, show the fading optical counterpart of the titanic blast. The object erupted in a brilliant flash of gamma rays and other electromagnetic radiation at 2:12 a.m. EDT on March 19, and was detected by Swift, NASA's gamma ray burst watchdog satellite. Immediately after the explosion, the gamma ray burst glowed as a dim 5th magnitude "star" in the spring constellation Bootes. Designated GRB 080319B, the intergalactic firework has been fading away ever since then. Hubble astronomers had hoped to see the host galaxy where the burst presumably originated, but were taken aback that the light from the GRB is still drowning out the galaxy's light even three weeks after the explosion. This is particularly surprising because it was such a bright GRB initially. Previously, bright bursts have tended to fade more rapidly, which fits in to the theory that brighter GRBs emit their energy in a more tightly confined beam. The slow fading leaves astronomers puzzling about just where the energy came from to power this GRB, and makes Hubble's next observations of this object in May all the more crucial. Called a long-duration gamma ray burst, such events are theorized to be caused by the death of a very massive star, perhaps weighing as much as 50 times our Sun. Such explosions, sometimes dubbed "hypernovae," are more powerful than ordinary supernova explosions and are far more luminous, in part because their energy seems to be concentrated into a blowtorch-like beam that, in this case, was aimed directly at Earth. The Hubble exposure also shows field galaxies around the fading optical component of the gamma ray burst, which are probably unrelated to the burst itself.

For more information, contact:
Ray Villard
Space Telescope Science Institute, Baltimore, Md.
410-338-4514
villard@stsci.edu

Nial Tanvir
University of Leicester
011-44-116-223-1217
nrt3@star.le.ac.uk

Andy Fruchter
Space Telescope Science Institute, Baltimore, Md.
410-338-5018
fruchter@stsci.edu

A delicate ribbon of gas floats eerily in our galaxy. A contrail from an alien spaceship? A jet from a black-hole? Actually this image, taken by NASA's Hubble Space Telescope, is a very thin section of a supernova remnant caused by a stellar explosion that occurred more than 1,000 years ago.

On or around May 1, 1006 A.D., observers from Africa to Europe to the Far East witnessed and recorded the arrival of light from what is now called SN 1006, a tremendous supernova explosion caused by the final death throes of a white dwarf star nearly 7,000 light-years away. The supernova was probably the brightest star ever seen by humans, and surpassed Venus as the brightest object in the night time sky, only to be surpassed by the moon. It was visible even during the day for weeks, and remained visible to the naked eye for at least two and a half years before fading away.

It wasn't until the mid-1960s that radio astronomers first detected a nearly circular ring of material at the recorded position of the supernova. The ring was almost 30 arcminutes across, the same angular diameter as the full moon. The size of the remnant implied that the blast wave from the supernova had expanded at nearly 20 million miles per hour over the nearly 1,000 years since the explosion occurred.

In 1976, the first detection of exceedingly faint optical emission of the supernova remnant was reported, but only for a filament located on the northwest edge of the radio ring. A tiny portion of this filament is revealed in detail by the Hubble observation. The twisting ribbon of light seen by Hubble corresponds to locations where the expanding blast wave from the supernova is now sweeping into very tenuous surrounding gas.

The hydrogen gas heated by this fast shock wave emits radiation in visible light. Hence, the optical emission provides astronomers with a detailed "snapshot" of the actual position and geometry of the shock front at any given time. Bright edges within the ribbon correspond to places where the shock wave is seen exactly edge on to our line of sight.

Today we know that SN 1006 has a diameter of nearly 60 light-years, and it is still expanding at roughly 6 million miles per hour. Even at this tremendous speed, however, it takes observations typically separated by years to see significant outward motion of the shock wave against the grid of background stars. In the Hubble image as displayed, the supernova would have occurred far off the lower right corner of the image, and the motion would be toward the upper left.

SN 1006 resides within our Milky Way Galaxy. Located more than 14 degrees off the plane of the galaxy's disk, there is relatively little confusion with other foreground and background objects in the field when trying to study this object. In the Hubble image, many background galaxies (orange extended objects) far off in the distant universe can be seen dotting the image. Most of the white dots are foreground or background stars in our Milky Way galaxy.

This image is a composite of hydrogen-light observations taken with Hubble's Advanced Camera for Surveys in February 2006 and Wide Field Planetary Camera 2 observations in blue, yellow-green, and near-infrared light taken in April 2008. The supernova remnant, visible only in the hydrogen-light filter was assigned a red hue in the Heritage color image.

For additional information, contact:

Ray Villard
Space Telescope Science Institute, Baltimore, Md.
410-338-4514
villard@stsci.edu

William Blair
Johns Hopkins University, Baltimore, Md.
410-516-8447
wpb@pha.jhu.edu

This image is a composite of visible (or optical), radio, and X-ray data of the full shell of the supernova remnant from SN 1006. The radio data show much of the extent that the X-ray image shows. In contrast, the visible light stems primarily from a small delicate filament along the northwest rim of the shell. The entire object has an angular size of roughly 30 arcminutes (0.5 degree, or about the size of the full moon), and a physical size of 60 light-years (18 parsecs) based on its distance of nearly 7,000 light-years. The small green box along the bright filament at the top of the image corresponds to the dimensions of the Hubble release image.

The optical data were obtained at the University of Michigan's 0.9- meter Curtis Schmidt telescope at the National Science Foundation's Cerro Tololo Inter-American Observatory (CTIO) near La Serena, Chile. CTIO is part of the National Optical Astronomy Observatory, which has its headquarters in Tucson, Ariz. H-alpha, continuum-subtracted data were provided by F. Winkler (Middlebury College) et al. The X-ray data were acquired from the Chandra X-ray Observatory's AXAF CCD Imaging Spectrometer (ACIS) at 0.5-3keV, and were provided by J. Hughes (Rutgers University) et al. The radio data, supplied by K. Dyer and collaborators Maddalena and Cornwell (NRAO, Socorro), were a composite from the National Radio Astronomy Observatory's Very Large Array (NRAO/VLA) in Socorro, New Mexico, along with NRAO's Green Bank Telescope (GBT) in Green Bank, West Virginia. These radio data were a mosaic at the 1.4 GHz frequency. Data of the supernova remnant were blended on a visible-light stellar background created using the Digitized Sky Survey's Anglo-Australian Observatory (AAO2) blue and red plates.

Comparison of visible hydrogen emission in the NW filament of SN 1006 in data taken at the CTIO 0.9m telescope (H-alpha, continuum-subtracted; Winkler, et al.) in 1998 (shown in green), and the Hubble ACS data (Raymond et. al) in 2006 (shown in red). The stellar background is from WFPC2 broadband B, V, and I data from 2008 (Hubble Heritage Team).

In what's beginning to look like a case of planetary measles, a third red spot has appeared alongside its cousins — the Great Red Spot and Red Spot Jr. — in the turbulent Jovian atmosphere.

This third red spot, which is a fraction of the size of the two other features, lies to the west of the Great Red Spot in the same latitude band of clouds.

The new red spot was previously a white oval-shaped storm. The change to a red color indicates its swirling storm clouds are rising to heights like the clouds of the Great Red Spot. One possible explanation is that the red storm is so powerful it dredges material from deep beneath Jupiter's cloud tops and lifts it to higher altitudes where solar ultraviolet radiation — via some unknown chemical reaction — produces the familiar brick color.

Detailed analysis of the visible-light images taken by Hubble's Wide Field Planetary Camera 2 on May 9 and 10, and near-infrared adaptive optics images taken by the W.M. Keck telescope on May 11, is revealing the relative altitudes of the cloud tops of the three red ovals. Because all three oval storms are bright in near-infrared light, they must be towering above the methane in Jupiter's atmosphere, which absorbs the Sun's infrared light and so looks dark in infrared images.

Turbulence and storms first observed on Jupiter more than two years ago are still raging, as revealed in the latest pictures. The Hubble and Keck images also reveal the change from a rather bland, quiescent band surrounding the Great Red Spot just over a year ago to one of incredible turbulence on both sides of the spot.

Red Spot Jr. appeared in spring of 2006. The Great Red Spot has persisted for as long as 200 to 350 years, based on early telescopic observations. If the new red spot and the Great Red Spot continue on their courses, they will encounter each other in August, and the small oval will either be absorbed or repelled from the Great Red Spot. Red Spot Jr. which lies between the two other spots, and is at a lower latitude, will pass the Great Red Spot in June.

The Hubble and Keck images may support the idea that Jupiter is in the midst of global climate change, as first proposed in 2004 by Phil Marcus, a professor of mechanical engineering at the University of California, Berkeley. The planet's temperatures may be changing by 15 to 20 degrees Fahrenheit. The giant planet is getting warmer near the equator and cooler near the South Pole. He predicted that large changes would start in the southern hemisphere around 2006, causing the jet streams to become unstable and spawn new vortices.

The Hubble team members are Imke de Pater, Phil Marcus, Mike Wong and Xylar Asay-Davis of the University of California, Berkeley, and Christopher Go of the Philippines. The Keck team members were de Pater, Wong, and Conor Laver of the University of California, Berkeley, and Al Conrad of the Keck Observatory. More information about the Keck observations is available in The University of California, Berkeley press release (http://www.berkeley.edu/news/media/releases/2008/05/22_redspots.shtml). The contributions by the amateur network (http://jupos.privat.t-online.de/) are invaluable for this research.

For additional information, contact:

Ray Villard
Space Telescope Science Institute, Baltimore, Md.
410-338-4514
villard@stsci.edu

Robert Sanders
University of California, Berkeley, Calif.
510-643-6998
rsanders@berkeley.edu

Mike Wong/Imke de Pater
University of California, Berkeley, Calif.
mikewong@astro.berkeley.edu/depater@astro.berkeley.edu

False color cylindrical map of Jupiter, constructed from a set of images of the planet obtained with the WFPC2 on the Hubble Space Telescope. Individual frames were obtained on May 9 and May 10, 2008. The images were deprojected and mosaiced together. The map shows latitudes between +/-70 deg. The resolution is a quarter degree in latitude and longitude. Images were combined at 673, 502, and 410 nm, as red, green, and blue colors.

False color cylindrical map of Jupiter, constructed from a set of images of the planet obtained with the WFPC2 on the Hubble Space Telescope. Individual frames were obtained on May 9 and May 10, 2008. The images were deprojected and mosaiced together. The map shows latitudes between +/-70 deg. The resolution is a quarter degree in latitude and longitude. Images were combined at 673, 502, and 410 nm, as red, green, and blue colors.

NASA's Hubble Space Telescope captures the magnificent starry population of the Coma Cluster of galaxies, one of the densest known galaxy collections in the universe.

The Hubble's Advanced Camera for Surveys viewed a large portion of the cluster, spanning several million light-years across. The entire cluster contains thousands of galaxies in a spherical shape more than 20 million light-years in diameter.

Also known as Abell 1656, the Coma Cluster is over 300 million light-years away. The cluster, named after its parent constellation Coma Berenices, is near the Milky Way's north pole. This places the Coma Cluster in an area unobscured by dust and gas from the plane of the Milky Way, and easily visible by Earth viewers.

Most of the galaxies that inhabit the central portion of the Coma Cluster are ellipticals. These featureless "fuzz-balls" are pale goldish brown in color and contain populations of old stars. Both dwarf, as well as giant ellipticals, are found in abundance in the Coma Cluster.

Farther out from the center of the cluster are several spiral galaxies. These galaxies have clouds of cold gas that are giving birth to new stars. Spiral arms and dust lanes "accessorize" these bright bluish-white galaxies that show a distinctive disk structure.

In between the ellipticals and spirals is a morphological class of objects known as S0 (S-zero) galaxies. They are made up of older stars and show little evidence of recent star formation; however, they do show some assemblage of structure — perhaps a bar or a ring, which may give rise to a more disk-like feature.

This Hubble image consists of a section of the cluster that is roughly one-third of the way out from the center of the cluster. One bright spiral galaxy is visible in the upper left of the image. It is distinctly brighter and bluer than galaxies surrounding it. A series of dusty spiral arms appears reddish brown against the whiter disk of the galaxy, and suggests that this galaxy has been disturbed at some point in the past. The other galaxies in the image are either ellipticals, S0 galaxies, or background galaxies far beyond the Coma Cluster sphere.

The data of the Coma Cluster were taken as part of a survey of a nearby rich galaxy cluster. Collectively they will provide a key database for studies of galaxy formation and evolution. This survey will also help to compare galaxies in different environments, both crowded and isolated, as well as to compare relatively nearby galaxies to more distant ones (at higher redshifts).

For additional information, contact:

Ray Villard
Space Telescope Science Institute, Baltimore, Md.
410-338-4514
villard@stsci.edu

Lars Lindberg Christensen
Hubble/ESA, Garching Germany
011-49-89-3200-6306
lars@eso.org

In studying the dimmest burned-out stars in globular star cluster NGC 6791, NASA's Hubble Space Telescope has uncovered a paradox: three different populations of stars exist in an object where all the stars should have formed at the same time out of an interstellar cloud of gas and dust.

[Left] — This is a ground-based telescopic view of NGC 6791, located 13,300 light-years away in the constellation Lyra. The green inset box shows the view with Hubble's Advanced Camera for Surveys.

[Top right] — The full Hubble Advanced Camera for Surveys field is full of stars estimated to be 8 billion years old. Two background galaxies can be seen at upper left.

[Bottom right] — A blow up of view of a small region of the Advanced Camera for Surveys field reveals very faint white dwarfs. The blue circles identify hotter dwarfs that are 4 billion years old. The red circles identify cooler dwarfs that are 6 billion years old.

The full Hubble Advanced Camera for Surveys field is full of stars estimated to be 8 billion years old. Two background galaxies can be seen at upper left.

A blow-up of view of a small region of the Advanced Camera for Surveys field reveals very faint white dwarfs. The hotter dwarfs are 4 billion years old and the cooler dwarfs are 6 billion years old.

This sequence of Hubble Space Telescope images offers an unprecedented view of a planetary game of Pac-Man among three red spots clustered together in Jupiter's atmosphere.

The time series shows the passage of the "Red Spot Jr." in a band of clouds below (south) of the Great Red Spot (GRS). "Red Spot Jr." first appeared on Jupiter in early 2006 when a previously white storm turned red. This is the second time, since turning red, it has skirted past its big brother apparently unscathed.

But this is not the fate of "baby red spot," which is in the same latitudinal band as the GRS. This new red spot first appeared earlier this year. The baby red spot gets ever closer to the GRS in this picture sequence until it is caught up in the anticyclonic spin of the GRS. In the final image the baby spot is deformed and pale in color and has been spun to the right (east) of the GRS. (Amateur astronomers' observations confirm that this is the baby spot that migrated around the GRS.) The prediction is that the baby spot will now get pulled back into the GRS "Cuisinart" and disappear for good. This is one possible mechanism that has powered and sustained the GRS for at least 150 years.

These three natural-color Jupiter images were made from data acquired on May 15, June 28, and July 8, 2008, by the Wide Field Planetary Camera 2 (WFPC2). Each one covers 58 degrees of Jovian latitude and 70 degrees of longitude (centered on 5 degrees South latitude and 110, 121, and 121 degrees West longitude, respectively).

For additional information, contact:

Ray Villard
Space Telescope Science Institute, Baltimore, Md.
410-338-4514
villard@stsci.edu

Amy Simon-Miller
NASA Goddard Space Flight Center, Greenbelt, Md.
301-286-6738
amy.simon@nasa.gov

This Hubble Space Telescope image of galaxy NGC 1275 reveals the fine, thread-like filamentary structures in the gas surrounding the galaxy. The red filaments are composed of cool gas being suspended by a magnetic field, and are surrounded by the 100-million-degree Fahrenheit hot gas in the center of the Perseus galaxy cluster.

The filaments are dramatic markers of the feedback process through which energy is transferred from the central massive black hole to the surrounding gas. The filaments originate when cool gas is transported from the center of the galaxy by radio bubbles that rise in the hot interstellar gas.

At a distance of 230 million light-years, NGC 1275 is one of the closest giant elliptical galaxies and lies at the center of the Perseus cluster of galaxies.

The galaxy was photographed in July and August 2006 with the Advanced Camera for Surveys in three color filters.

The active galaxy NGC 1275 is also a well-known radio source (Perseus A) and a strong emitter of X-rays due to the presence of a black hole in the center of the galaxy. The behemoth also lies at the center of the cluster of galaxies known as the Perseus Cluster. By combining multi-wavelength images into a single composite, the dynamics of the galaxy are more easily visible. Detail and structure from X-ray, optical, and radio wavelengths combine for an aesthetically pleasing, but nonetheless violent depiction of events going on at the heart of the galaxy.

X-ray data from the Chandra X-ray Observatory's Advanced CCD Imaging Spectrometer and radio data from NRAO's Very Large Array were combined with optical wavelengths in the red, green, and blue from Hubble's Advanced Camera for Surveys. In the composite image, the X-ray data contribute to the soft violet shells around the outside of the center. The pinkish lobes toward the center of the galaxy are from radio frequencies. The radio emission, tracing jets from the black hole, fills the X-ray cavities. Dust lanes, star-forming regions, hydrogen filaments, foreground stars, and background galaxies are contributions from the Hubble optical data.

These images show four spiral galaxies with bars of stars and gas slicing through them.

The galaxies are at various distances from Earth. The galaxy at upper left is 2.1 billion light-years away; the galaxy at upper right, 3.8 billion light-years away; the galaxy at lower left, 5.3 billion light-years away; and the galaxy at lower right, 6.4 billion light-years away.

The galaxies are part of a landmark study of more than 2,000 spiral galaxies from the largest galaxy census conducted by the Advanced Camera for Surveys aboard NASA's Hubble Space Telescope.

The survey's results show that so-called barred spiral galaxies were far less plentiful over the last 7 billion years than they are today, in the local universe. The study's results confirm the idea that bars are a sign of galaxies reaching full maturity as the "formative years" end. The observations are part of the Cosmic Evolution Survey (COSMOS).

COSMOS covers an area of sky nine times larger than the full Moon, surveying 10 times more spiral galaxies than previous observations.

Astronomers assembled these images from observations taken with Hubble and the Subaru Telescope in Mauna Kea, Hawaii.

The observations were taken between fall 2003 and spring 2005.

Barred spiral galaxy COSMOS 3127341 is located 2.1 billion light-years away from Earth. The galaxy is part of a landmark study of more than 2,000 spiral galaxies from the largest galaxy census conducted by the Advanced Camera for Surveys aboard NASA's Hubble Space Telescope. The observations are part of the Cosmic Evolution Survey (COSMOS). Astronomers assembled this image from observations taken between fall 2003 and spring 2005 with Hubble and the Subaru Telescope in Mauna Kea, Hawaii.

Barred spiral galaxy COSMOS 1705033 is located 3.8 billion light-years away from Earth. The galaxy is part of a landmark study of more than 2,000 spiral galaxies from the largest galaxy census conducted by the Advanced Camera for Surveys aboard NASA's Hubble Space Telescope. The observations are part of the Cosmic Evolution Survey (COSMOS). Astronomers assembled this image from observations taken between fall 2003 and spring 2005 with Hubble and the Subaru Telescope in Mauna Kea, Hawaii.

Barred spiral galaxy COSMOS 1161898 is located 5.3 billion light-years away from Earth. The galaxy is part of a landmark study of more than 2,000 spiral galaxies from the largest galaxy census conducted by the Advanced Camera for Surveys aboard NASA's Hubble Space Telescope. The observations are part of the Cosmic Evolution Survey (COSMOS). Astronomers assembled this image from observations taken between fall 2003 and spring 2005 with Hubble and the Subaru Telescope in Mauna Kea, Hawaii.

Barred spiral galaxy COSMOS 2607238 is located 6.4 billion light-years away from Earth. The galaxy is part of a landmark study of more than 2,000 spiral galaxies from the largest galaxy census conducted by the Advanced Camera for Surveys aboard NASA's Hubble Space Telescope. The observations are part of the Cosmic Evolution Survey (COSMOS). Astronomers assembled this image from observations taken between fall 2003 and spring 2005 with Hubble and the Subaru Telescope in Mauna Kea, Hawaii.

These images taken by NASA's Hubble Space Telescope show four members of the Virgo cluster of galaxies, the nearest large galaxy cluster to Earth.

They are part of a survey of globular star clusters in 100 of Virgo's galaxies. Globular clusters, dense bunches of hundreds of thousands of stars, have some of the oldest surviving stars in the universe. Most of the star clusters in the Virgo survey are older than 5 billion years.

The galaxy at top, left, NGC 4660, contains 205 globular clusters. The galaxy at top, right, NGC 4458, has 72. Both galaxies possess a typical number of globular clusters for their size and brightness.

IC 3506, at bottom, left, is a dwarf galaxy near Virgo's central hub that contains 31 globular clusters. By contrast, the dwarf galaxy VCC 1993, at bottom, right, has no clusters and resides in Virgo's outskirts.

The Hubble study found evidence that globular clusters are more likely to form in dense areas, where star birth occurs at a rapid rate, instead of uniformly from galaxy to galaxy. Dwarf galaxy IC 3506, for example, resides near Virgo's dense center and has four times as many clusters for its size and brightness as NGC 4660 and NGC 4458.

Hubble's "eye" is so sharp that it was able to pick out the fuzzy globular clusters, which, at that distance, look like individual stars bunched up around the galaxies, instead of groupings of stars.

Comprised of over 2,000 galaxies, the Virgo cluster is located about 54 million light-years away.

Astronomers made these composite images from the advanced camera's full field-of-view observations. They also used modeling data to fill in a narrow gap between the camera's detectors. The images were taken from December 2002 to December 2003.

The monstrous elliptical galaxy M87 is the home of several trillion stars, a supermassive black hole, and a family of 15,000 globular star clusters.

M87 is the dominant galaxy at the center of the neighboring Virgo cluster of galaxies, which contains some 2,000 galaxies.

Amid the smooth, yellow population of older stars, the two features that stand out most in this Hubble Space Telescope image of M87 are its soft blue jet and the myriad of starlike globular clusters scattered throughout the image.

The jet is a black-hole-powered stream of material that is being ejected from the core of the galaxy. As gaseous material from the center of the galaxy accretes onto the black hole, the resultant energy released produces a fire-hose stream of subatomic particles that are accelerated to velocities near the speed of light.

Being in the center of the Virgo cluster of galaxies, M87 may have accumulated some of its globular clusters by gravitationally pulling them from nearby dwarf galaxies that seem to be devoid of globulars today.

The 120,000-light-year-diameter galaxy lies at a distance of 54 million light-years from the Sun in the spring constellation Virgo.

This image was made from data taken in 2003 and 2006 with Hubble's Advanced Camera for Surveys. The image is a composite of individual filtered data that cover the visible and infrared portions of the spectrum.

These images taken by NASA's Hubble Space Telescope show the globular cluster systems of 100 galaxies observed within the Advanced Camera for Surveys (ACS) Virgo Cluster Survey. Globular clusters, dense bunches of hundreds of thousands of stars, have some of the oldest surviving stars in the universe. Most of the star clusters in the Virgo survey are older than 5 billion years. The Hubble study found evidence that these globular clusters are more likely to form in dense areas where star birth occurs at a rapid rate, instead of uniformly from galaxy to galaxy. Comprised of over 2,000 galaxies and located about 54 million light-years away, the Virgo cluster is the nearest large galaxy cluster to Earth. These composite images were made from the advanced camera's full field-of-view observations. Astronomers also used modeling data to fill in a narrow gap between the camera's detectors. The images were taken from December 2002 to December 2003.

This image is a composite of visible (or optical), radio, and X-ray data of the giant elliptical galaxy, M87. M87 lies at a distance of 54 million light-years and is the largest galaxy in the Virgo cluster of galaxies. Bright jets moving at close to the speed of light are seen at all wavelengths coming from the massive black hole at the center of the galaxy. It has also been identified with the strong radio source, Virgo A, and is a powerful source of X-rays as it resides near the center of a hot, X-ray–emitting cloud that extends over much of the Virgo cluster. The extended radio emission consists of plumes of relativistic (extremely hot) gas from the jets rising into the X-ray–emitting cluster medium.

The optical data of M87 were obtained with Hubble's Advanced Camera for Surveys in visible and infrared filters (data courtesy of P. Cote (Herzberg Institute of Astrophysics) and E. Baltz (Stanford University)). Wide-field optical data of the center of the Virgo Cluster were also provided by R. Gendler (Copyright Robert Gendler 2006). The X-ray data were acquired from the Chandra X-ray Observatory's CCD Imaging Spectrometer (ACIS), and were provided by W. Forman (Harvard- Smithsonian Center for Astrophysics) et al. The radio data were obtained by W. Cotton using the National Radio Astronomy Observatory's Very Large Array (NRAO/VLA) near Socorro, New Mexico. NRAO archive VLA data of M87 were also used in the composite radio image.

In commemoration of NASA's Hubble Space Telescope completing its 100,000th orbit in its 18th year of exploration and discovery, scientists at the Space Telescope Science Institute in Baltimore, Md., have aimed Hubble to take a snapshot of a dazzling region of celestial birth and renewal.

Hubble peered into a small portion of the nebula near the star cluster NGC 2074 (upper, left). The region is a firestorm of raw stellar creation, perhaps triggered by a nearby supernova explosion. It lies about 170,000 light-years away near the Tarantula nebula, one of the most active star-forming regions in our Local Group of galaxies.

The three-dimensional-looking image reveals dramatic ridges and valleys of dust, serpent-head "pillars of creation," and gaseous filaments glowing fiercely under torrential ultraviolet radiation. The region is on the edge of a dark molecular cloud that is an incubator for the birth of new stars.

The high-energy radiation blazing out from clusters of hot young stars already born in NGC 2074 is sculpting the wall of the nebula by slowly eroding it away. Another young cluster may be hidden beneath a circle of brilliant blue gas at center, bottom.

In this approximately 100-light-year-wide fantasy-like landscape, dark towers of dust rise above a glowing wall of gases on the surface of the molecular cloud. The seahorse-shaped pillar at lower, right is approximately 20 light-years long, roughly four times the distance between our Sun and the nearest star, Alpha Centauri.

The region is in the Large Magellanic Cloud (LMC), a satellite of our Milky Way galaxy. It is a fascinating laboratory for observing star-formation regions and their evolution. Dwarf galaxies like the LMC are considered to be the primitive building blocks of larger galaxies.

This representative color image was taken on August 10, 2008, with Hubble's Wide Field Planetary Camera 2. Red shows emission from sulfur atoms, green from glowing hydrogen, and blue from glowing oxygen.

For additional information, contact:

Ray Villard / Cheryl Gundy / Donna Weaver
Space Telescope Science Institute, Baltimore, Md.
410-338-4514 / 410-338-4707 / 410-338-4493
villard@stsci.edu / gundy@stsci.edu / dweaver@stsci.edu

Mario Livio
Space Telescope Science Institute, Baltimore, Md.
410-338-4439
mlivio@stsci.edu

NASA's Hubble Space Telescope reached a milestone of 100,000 orbits at 7:42 a.m. EDT on Monday, August 11, 2008. At that time the telescope was flying above the midway point of the Pacific Ocean and directly over the equator, heading northward. Hubble completes an orbit around Earth approximately once every 90 minutes.

A powerful collision of galaxy clusters has been captured by NASA's Hubble Space Telescope and Chandra X-ray Observatory. This clash of clusters provides striking evidence for dark matter and insight into its properties.

The observations of the cluster known as MACS J0025.4-1222 indicate that a titanic collision has separated the dark from ordinary matter and provide an independent confirmation of a similar effect detected previously in a target dubbed the Bullet Cluster. These new results show that the Bullet Cluster is not an anomalous case.

MACS J0025 formed after an enormously energetic collision between two large clusters. Using visible-light images from Hubble, the team was able to infer the distribution of the total mass — dark and ordinary matter. Hubble was used to map the dark matter (colored in blue) using a technique known as gravitational lensing. The Chandra data enabled the astronomers to accurately map the position of the ordinary matter, mostly in the form of hot gas, which glows brightly in X-rays (pink).

As the two clusters that formed MACS J0025 (each almost a whopping quadrillion times the mass of the Sun) merged at speeds of millions of miles per hour, the hot gas in the two clusters collided and slowed down, but the dark matter passed right through the smashup. The separation between the material shown in pink and blue therefore provides observational evidence for dark matter and supports the view that dark-matter particles interact with each other only very weakly or not at all, apart from the pull of gravity.

The international team of astronomers in this study was led by Marusa Bradac of the University of California, Santa Barbara, and Steve Allen of the Kavli Institute for Particle Astrophysics and Cosmology at Stanford University and the Stanford Linear Accelerator Center (SLAC). Their results will appear in an upcoming issue of The Astrophysical Journal.

For additional information, contact:

Ray Villard
Space Telescope Science Institute, Baltimore, Md.
410-338-4514
villard@stsci.edu

Megan Watzke
Chandra X-ray Center, Cambridge, Mass.
617-496-7998
cxcpress@cfa.harvard.edu

NASA's Hubble Space Telescope has captured a rare alignment between two spiral galaxies. The outer rim of a small, foreground galaxy is silhouetted in front of a larger background galaxy. Skeletal tentacles of dust can be seen extending beyond the small galaxy's disk of starlight.

Such outer dark dusty structures, which appear to be devoid of stars, like barren branches, are rarely so visible in a galaxy because there is usually nothing behind them to illuminate them. Astronomers have never seen dust this far beyond the visible edge of a galaxy. They do not know if these dusty structures are common features in galaxies.

Understanding a galaxy's color and how dust affects and dims that color are crucial to measuring a galaxy's true brightness. By knowing the true brightness, astronomers can calculate the galaxy's distance from Earth.

Astronomers calculated that the background galaxy is 780 million light-years away. They have not as yet calculated the distance between the two galaxies, although they think the two are relatively close, but not close enough to interact. The background galaxy is about the size of the Milky Way Galaxy and is about 10 times larger than the foreground galaxy.

Most of the stars speckled across this image belong to the nearby spiral galaxy NGC 253, which is out of view to the right. Astronomers used Hubble's Advanced Camera for Surveys to snap images of NGC 253 when they spied the two galaxies in the background. From ground-based telescopes, the two galaxies look like a single blob. But the Advanced Camera's sharp "eye" distinguished the blob as two galaxies, cataloged as 2MASX J00482185-2507365. The images were taken on Sept. 19, 2006.

The results have been submitted for publication in The Astronomical Journal.

For additional information, contact:

Donna Weaver/Ray Villard
Space Telescope Science Institute, Baltimore, Md.
410-338-4493 / 410-338-4514
dweaver@stsci.edu / villard@stsci.edu

Benne Holwerda
Space Telescope Science Institute, Baltimore, Md.
/University of Cape Town, South Africa
holwerda@stsci.edu

The landmark 10th anniversary of the Hubble Space Telescope's Hubble Heritage Project is being celebrated with a 'landscape' image from the cosmos. Cutting across a nearby star-forming region are the "hills and valleys" of gas and dust displayed in intricate detail. Set amid a backdrop of soft, glowing blue light are wispy tendrils of gas as well as dark trunks of dust that are light-years in height.

The Hubble Heritage Project, which began in October 1998, has released nearly 130 images mined from the Hubble data archive as well as a number of observations taken specifically for the project. By releasing a new, previously unseen Hubble image every month, the team's intent was to showcase some of the most attractive images ever taken by the Hubble telescope, and share them with a wide audience. The Heritage team continues to create aesthetic images that present the universe from an artistic perspective.

This month's three-dimensional-looking Hubble image shows the edge of the giant gaseous cavity within the star-forming region called NGC 3324. The glowing nebula has been carved out by intense ultraviolet radiation and stellar winds from several hot, young stars. A cluster of extremely massive stars, located well outside this image in the center of the nebula, is responsible for the ionization of the nebula and excavation of the cavity.

The image also reveals dramatic dark towers of cool gas and dust that rise above the glowing wall of gas. The dense gas at the top resists the blistering ultraviolet radiation from the central stars, and creates a tower that points in the direction of the energy flow. The high-energy radiation blazing out from the hot, young stars in NGC 3324 is sculpting the wall of the nebula by slowly eroding it away.

Located in the Southern Hemisphere, NGC 3324 is at the northwest corner of the Carina Nebula (NGC 3372), home of the Keyhole Nebula and the active, outbursting star Eta Carinae. The entire Carina Nebula complex is located at a distance of roughly 7,200 light-years, and lies in the constellation Carina.

This image is a composite of data taken with two of Hubble's science instruments. Data taken with the Advanced Camera for Surveys (ACS) in 2006 isolated light emitted by hydrogen. More recent data, taken in 2008 with the Wide Field Planetary Camera 2 (WFPC2), isolated light emitted by sulfur and oxygen gas. To create a color composite, the data from the sulfur filter are represented by red, from the oxygen filter by blue, and from the hydrogen filter by green.

The Heritage project has released images using several of Hubble's optical cameras: the Wide Field Planetary Camera (WF/PC), which was installed when the telescope was first deployed in 1990; WFPC2, which replaced WFPC in 1993 and is still in service today; and ACS, which was added in 2002. After the Hubble Servicing Mission in early 2009, the Hubble Heritage team hopes to continue using ACS as well as the newest of the optical cameras, Wide Field Camera 3.

For additional information, contact:

Ray Villard
Space Telescope Science Institute, Baltimore, Md.
410-338-4514
villard@stsci.edu

Keith Noll
Space Telescope Science Institute, Baltimore, Md.
410-338-1828
noll@stsci.edu

Nathan Smith
University of California, Berkeley, Calif.
nathans@astro.berkeley.edu

These images taken with NASA's Hubble Space Telescope are close-up views of four galaxies from a large survey of nearby galaxies.

The galaxies have very different masses and sizes and showcase the diversity of galaxies found in the ANGST study. Although the galaxies are separated by many light-years, they are presented as if they are all at the same distance to show their relative sizes.

The images, taken with Hubble's Advanced Camera for Surveys, reveal rich detail in the stellar populations and in the interstellar dust scattered between the stars. Hubble's sharp views reveal the colors and brightnesses of individual stars, which astronomers used to derive the history of star formation in each galaxy.

In the composite image at the top, NGC 253 is ablaze with the light from thousands of young, blue stars. The spiral galaxy is undergoing intense star formation. The image demonstrates the sharp "eye" of the Advanced Camera, which resolved individual stars. The dark filaments are clouds of dust and gas. NGC 253 is the dominant galaxy in the Sculptor Group of galaxies and it resides about 13 million light-years from Earth.

In the view of the spiral galaxy NGC 300, second from top, young, blue stars are concentrated in spiral arms that sweep diagonally through the image. The yellow blobs are glowing hot gas that has been heated by radiation from the nearest young, blue stars. NGC 300 is a member of the Sculptor Group of galaxies and it is located 7 million light-years away.

The dark clumps of material scattered around the bright nucleus of NGC 3077, the small, dense galaxy at bottom, left, are pieces of wreckage from the galaxy's interactions with its larger neighbors. NGC 3077 is a member of the M81 group of galaxies and it resides 12.5 million light-years from Earth.

The image at bottom, right, shows a swarm of young, blue stars in the diffuse dwarf irregular galaxy NGC 4163. NGC 4163 is a member of a group of dwarf galaxies near our Milky Way and is located roughly 10 million light-years away.

These galaxies are part of a detailed survey called the ACS Nearby Galaxy Survey Treasury program (ANGST). In the census, Hubble observed roughly 14 million stars in 69 galaxies. The survey explored a region called the "Local Volume," and the galaxy distances ranged from 6.5 million light-years to 13 million light-years from Earth. The Local Volume resides beyond the Local Group of galaxies, an even nearer collection of a few dozen galaxies within about 3 million light-years of our Milky Way Galaxy.

The natural-color images were constructed using observations taken in infrared, visible, and blue light. The observations of NGC 253 and NGC 300 were taken in September 2006; of NGC 3077 in November 2006; and of NGC 4163 in December 2006.

These images taken by NASA's Hubble Space Telescope capture three close-up views of the spiral galaxy NGC 300, a member of the Sculptor Group of galaxies near our Milky Way. NGC 300 resides 7 million light-years from Earth.

In the image at far left, Hubble resolves a dense swarm of stars, patches of dust, and a bright central star cluster. This cluster lies at the very nucleus of the galaxy. Similar clusters are thought to be related to the formation of supermassive black holes. The image at center shows a star-forming region a few thousand light-years farther from the galaxy's center. The yellow blobs are the glow from hot gas that has been heated by radiation from the nearest young, blue stars. The image at far right reveals more diffuse groupings of young, blue stars, farther away from the galaxy's center, along with faint shells of hot gas.

NGC 300 is part of a detailed survey called the ACS Nearby Galaxy Survey Treasury program (ANGST). In this census Hubble observed roughly 14 million stars in 69 galaxies. The survey explored a region called the "Local Volume," and the galaxy distances ranged from 6.5 million light-years to 13 million light-years from Earth. The Local Volume resides beyond the Local Group of galaxies, an even nearer collection of a few dozen galaxies within about 3 million light-years of our Milky Way Galaxy.

The natural-color images were constructed using observations taken in infrared, visible, and blue light. The observations were made in November 2006 with Hubble's Advanced Camera for Surveys.

A close-up view from Hubble shows that NGC 253 is ablaze with the light from thousands of young, blue stars. The spiral galaxy is undergoing intense star formation. This image, taken with Hubble's Advanced Camera for Surveys, reveals colors and differing intensities of individual stars as well dark filaments of dust and gas interstellar dust intersperced among the stars. NGC 253 is the dominant galaxy in the Sculptor Group of galaxies and resides about 13 million light-years from Earth.

This galaxy is part of a detailed survey called the ACS Nearby Galaxy Survey Treasury program (ANGST). The natural-color images were constructed using Hubble observations taken in infrared, visible, and blue light. Data from the Cerro Tololo Inter-American Observatory in Chile were used to fill in small gaps in the Hubble image of NGC 253.

NASA's Hubble Space Telescope is back in business.

Just a couple of days after the orbiting observatory was brought back online, Hubble aimed its prime working camera, the Wide Field Planetary Camera 2 (WFPC2), at a particularly intriguing target, a pair of gravitationally interacting galaxies called Arp 147.

The image demonstrated that the camera is working exactly as it was before going offline, thereby scoring a "perfect 10" both for performance and beauty.

The two galaxies happen to be oriented so that they appear to mark the number 10. The left-most galaxy, or the "one" in this image, is relatively undisturbed apart from a smooth ring of starlight. It appears nearly on edge to our line of sight. The right-most galaxy, resembling a zero, exhibits a clumpy, blue ring of intense star formation.

The blue ring was most probably formed after the galaxy on the left passed through the galaxy on the right. Just as a pebble thrown into a pond creates an outwardly moving circular wave, a propagating density wave was generated at the point of impact and spread outward. As this density wave collided with material in the target galaxy that was moving inward due to the gravitational pull of the two galaxies, shocks and dense gas were produced, stimulating star formation.

The dusty reddish knot at the lower left of the blue ring probably marks the location of the original nucleus of the galaxy that was hit.

Arp 147 appears in the Arp Atlas of Peculiar Galaxies, compiled by Halton Arp in the 1960s and published in 1966. This picture was assembled from WFPC2 images taken with three separate filters. The blue, visible-light, and infrared filters are represented by the colors blue, green, and red, respectively.

The galaxy pair was photographed on October 27-28, 2008. Arp 147 lies in the constellation Cetus, and it is more than 400 million light-years away from Earth.

For additional information, contact:

Ray Villard
Space Telescope Science Institute, Baltimore, Md.
410-338-4514
villard@stsci.edu

Mario Livio
Space Telescope Science Institute, Baltimore, Md.
410-338-4439
mlivio@stsci.edu

This image taken by NASA's Hubble Space Telescope showcases the brilliant core of one of the most active galaxies in our local neighborhood. The entire core is 5,000 light-years wide.

The galaxy, called NGC 1569, sparkles with the light from millions of newly formed young stars. NGC 1569 is pumping out stars at a rate that is 100 times faster than the rate observed in our Milky Way Galaxy. This frenzied pace has been almost continuous for the past 100 million years.

The core's centerpiece is a grouping of three giant star clusters, each containing more than a million stars. (Two of the clusters are so close they appear as one grouping.) The clusters reside in a large, central cavity. The gas in the cavity has been blown out by the multitude of massive, young stars that already exploded as supernovae. These explosions also triggered a violent flow of gas and particles that is sculpting giant gaseous structures. The sculpted structure at lower right is about 3,700 light-years long.

Huge bubbles of gas, such as the two at left, appear like floating islands. The largest bubble is about 378 light-years wide and the smallest 119 light-years wide. They are being illuminated by the radiation from the bright, young stars within them. Some of those stars are peeking through their gaseous cocoons.

The biggest and brightest objects surrounding the core are stars scattered throughout our Milky Way Galaxy. In contrast, the thousands of tiny white dots in the image are stars in the halo of NGC 1569. The galaxy is 11 million light-years from Earth.

A new analysis of NGC 1569 shows that it is one and a half times farther from Earth than astronomers previously thought. The extra distance places the galaxy in the middle of a group of about 10 galaxies centered on the spiral galaxy IC 342. Gravitational interactions among the group's galaxies may be compressing gas in NGC 1569 and igniting the star-birthing frenzy.

Hubble's Wide Field Planetary Camera 2 and Advanced Camera for Surveys made the observations of NGC 1569 in September 1999, November 2006, and January 2007.

NASA's Hubble Space Telescope has imaged one of the most active galaxies in our local neighborhood. NGC 1569, sparkles with the light from millions of newly formed young stars. At the nucleus of the starburst galaxy is a grouping of three giant star clusters, each containing more than a million stars. The clusters reside in a large, central cavity. The gas in the cavity has been blown out by the multitude of massive, young stars that already exploded as supernovae. NGC 1569 is located 11 million light-years from Earth in the constellation Camelopardalis. Hubble's Wide Field Planetary Camera 2 and Advanced Camera for Surveys made the observations of NGC 1569 in September 1999, November 2006, and January 2007. This image shows the full region that was imaged by both detectors.

This image, taken with the Advanced Camera for Surveys aboard NASA's Hubble Space Telescope, shows the newly discovered planet, Fomalhaut b, orbiting its parent star, Fomalhaut.

The small white box at lower right pinpoints the planet's location. Fomalhaut b has carved a path along the inner edge of a vast, dusty debris ring encircling Fomalhaut that is 21.5 billion miles across. Fomalhaut b lies 1.8 billion miles inside the ring's inner edge and orbits 10.7 billion miles from its star.

The inset at bottom right is a composite image showing the planet's position during Hubble observations taken in 2004 and 2006. Astronomers have calculated that Fomalhaut b completes an orbit around its parent star every 872 years.

The white dot in the center of the image marks the star's location. The region around Fomalhaut's location is black because astronomers used the Advanced Camera's coronagraph to block out the star's bright glare so that the dim planet could be seen. Fomalhaut b is 1 billion times fainter than its star. The radial streaks are scattered starlight. The red dot at lower left is a background star.

The Fomalhaut system is 25 light-years away in the constellation Piscis Australis.

This false-color image was taken in October 2004 and July 2006.

Like a whirl of shiny flakes sparkling in a snow globe, Hubble catches an instantaneous glimpse of many hundreds of thousands of stars moving about in the globular cluster M13, one of the brightest and best-known globular clusters in the northern sky. This glittering metropolis of stars is easily found in the winter sky in the constellation Hercules and can even be glimpsed with the unaided eye under dark skies.

M13 is home to over 100,000 stars and located at a distance of 25,000 light-years. These stars are packed so closely together in a ball, approximately 150 light-years across, that they will spend their entire lives whirling around in the cluster.

Near the core of this cluster, the density of stars is about a hundred times greater than the density in the neighborhood of our sun. These stars are so crowded that they can, at times, slam into each other and even form a new star, called a "blue straggler."

The brightest reddish stars in the cluster are ancient red giants. These aging stars have expanded to many times their original diameters and cooled. The blue-white stars are the hottest in the cluster.

Globular clusters can be found spread largely in a vast halo around our galaxy. M13 is one of nearly 150 known globular clusters surrounding our Milky Way galaxy.

Globular clusters have some of the oldest stars in the universe. They likely formed before the disk of our Milky Way, so they are older than nearly all other stars in our galaxy. Studying globular clusters therefore tells us about the history of our galaxy.

This image is a composite of archival Hubble data taken with the Wide Field Planetary Camera 2 and the Advanced Camera for Surveys. Observations from four separate science proposals taken in November 1999, April 2000, August 2005, and April 2006 were used. The image includes broadband filters that isolate light from the blue, visible, and infrared portions of the spectrum.

For additional information, contact:

Ray Villard
Space Telescope Science Institute, Baltimore, Md.
410-338-4514
villard@stsci.edu

Keith Noll
Space Telescope Science Institute, Baltimore, Md.
410-338-1828
noll@stsci.edu

Hubble catches an instantaneous glimpse of many hundreds of thousands of stars moving about in the globular cluster M13, one of the brightest and best-known globular clusters in the northern sky. This glittering metropolis of stars is easily found in the winter sky in the constellation Hercules. This image is a composite of archival Hubble data taken with the Wide Field Planetary Camera 2 and the Advanced Camera for Surveys. Observations from four separate science proposals taken in November 1999, April 2000, August 2005, and April 2006 were used. The image includes broadband filters that isolate light from the blue, visible, and infrared portions of the spectrum.

NASA's Hubble Space Telescope has caught Jupiter's moon Ganymede playing a game of "peek-a-boo." In this crisp Hubble image, Ganymede is shown just before it ducks behind the giant planet.

Ganymede completes an orbit around Jupiter every seven days. Because Ganymede's orbit is tilted nearly edge-on to Earth, it routinely can be seen passing in front of and disappearing behind its giant host, only to reemerge later.

Composed of rock and ice, Ganymede is the largest moon in our solar system. It is even larger than the planet Mercury. But Ganymede looks like a dirty snowball next to Jupiter, the largest planet in our solar system. Jupiter is so big that only part of its Southern Hemisphere can be seen in this image.

Hubble's view is so sharp that astronomers can see features on Ganymede's surface, most notably the white impact crater, Tros, and its system of rays, bright streaks of material blasted from the crater. Tros and its ray system are roughly the width of Arizona.

The image also shows Jupiter's Great Red Spot, the large eye-shaped feature at upper left. A storm the size of two Earths, the Great Red Spot has been raging for more than 300 years. Hubble's sharp view of the gas giant planet also reveals the texture of the clouds in the Jovian atmosphere as well as various other storms and vortices.

Astronomers use these images to study Jupiter's upper atmosphere. As Ganymede passes behind the giant planet, it reflects sunlight, which then passes through Jupiter's atmosphere. Imprinted on that light is information about the gas giant's atmosphere, which yields clues about the properties of Jupiter's high-altitude haze above the cloud tops.

This color image was made from three images taken on April 9, 2007, with the Wide Field Planetary Camera 2 in red, green, and blue filters. The image shows Jupiter and Ganymede in close to natural colors.

For additional information, contact:

Donna Weaver / Ray Villard
Space Telescope Science Institute, Baltimore, Md.
410-338-4493 / 410-338-4514
dweaver@stsci.edu / villard@stsci.edu

Erich Karkoschka
University of Arizona, Lunar and Planetary Lab
520-621-3994
erich@lpl.arizona.edu

This series of images taken with NASA's Hubble Space Telescope shows Jupiter's largest moon, Ganymede, disappearing behind the planet.

Ganymede completes an orbit around Jupiter every seven days. Because Ganymede's orbit is tilted nearly edge-on to Earth, it routinely can be seen playing a game of "peek-a- boo," passing in front of and disappearing behind its giant host, only to reemerge later. Composed of rock and ice, Ganymede is the largest moon in our solar system. It is even larger than the planet Mercury.

The top images show Ganymede next to Jupiter. The images were taken in blue and red light on Jan. 19, 2005 with Hubble's Advanced Camera for Surveys. The close-up images at bottom follow Ganymede as it ducks behind Jupiter a few minutes later.

This pair of NASA Hubble Space Telescope images of the binary brown dwarf Kelu-1 trace the orbital motion of the two stars over a seven-year span as photographed by the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) on Hubble.

In 1998, the "stars" were too close together to be resolved by Hubble. By 2005, they had moved apart to a separation of 520 million miles. The projected maximum separation is 550 million miles.

Binary systems allow astronomers to estimate the mass of companion objects. The brown dwarfs are 61 and 50 times the mass of Jupiter. They are therefore too small to burn as stars, but too large to have formed as planets. Based on the total estimated mass of the system, astronomers suspect there is a third brown dwarf member that has not yet been resolved.

NEED CAPTION

NEED CAPTION

This composite color infrared image of the center of our Milky Way galaxy reveals a new population of massive stars and new details in complex structures in the hot ionized gas swirling around the central 300 light-years. This sweeping panorama is the sharpest infrared picture ever made of the Galactic core. It offers a nearby laboratory for how massive stars form and influence their environment in the often violent nuclear regions of other galaxies.

This view combines the sharp imaging of the Hubble Space Telescope's Near Infrared Camera and Multi-Object Spectrometer (NICMOS) with color imagery from a previous Spitzer Space Telescope survey done with its Infrared Astronomy Camera (IRAC). The Galactic core is obscured in visible light by intervening dust clouds, but infrared light penetrates the dust.

The spatial resolution of the NICMOS image corresponds to 0.025 light-years at the distance of the Galactic core of 26,000 light-years. Hubble reveals details in objects as small as 20 times the size of our own solar system.

The NICMOS mosaic image represents the largest piece of sky ever mapped for one NICMOS observing program. It was combined with a full-color Spitzer image to yield a color composite of the nuclear region. The picture measures 300 x 115 light-years. Outside the boundary of the NICMOS survey, the IRAC exposures (which are 1/10th as sharp) can be seen at wavelengths of 3.6 microns (shown as blue), 4.5 microns (shown as green), 5.8 microns (shown as orange), and 8.0 microns (shown as red).

The new NICMOS data show the glow from ionized hydrogen gas as well as a multitude of stars. Hubble reveals an important population of stars with strong stellar winds, signified by excess emission from ionized gas at one infrared wavelength (1.87 microns) compared to another slightly different wavelength (1.90 microns).

NICMOS shows a large number of these massive stars distributed throughout the region. A new finding is that astronomers now see that the massive stars are not confined to one of the three known clusters of massive stars in the Galactic Center, known as the Central cluster, the Arches cluster, and the Quintuplet cluster. These three clusters are easily seen as tight concentrations of bright, massive stars in the NICMOS image. The distributed stars may have formed in isolation, or they may have originated in clusters that have been disrupted by strong gravitational tidal forces.

The winds and radiation from these stars form the complex structures seen in the core, and in some cases, they may be triggering new generations of stars. At upper left, large arcs of ionized gas are resolved into arrays of intriguingly organized linear filaments indicating perhaps a critical role of the influence of locally strong magnetic fields.

The lower left region shows pillars of gas sculpted by winds from hot massive stars in the Quintuplet cluster. At the center of the image, ionized gas surrounding the supermassive black hole at the center of the galaxy is confined to a bright spiral embedded within a circum-nuclear dusty inner-tube-shaped torus.

The NICMOS mosaic required 144 Hubble orbits to make 2,304 science exposures. It was taken between February 22 and June 5, 2008.

This NASA Hubble Space Telescope infrared mosaic image represents the sharpest survey of the Galactic Center to date. It reveals a new population of massive stars and new details in complex structures in the hot ionized gas swirling around the central 300 x 115 light-years. This sweeping infrared panorama offers a nearby laboratory for how massive stars form and influence their environment in the often violent nuclear regions of other galaxies.

The infrared mosaic was taken with Hubble's Near Infrared Camera and Multi-Object Spectrometer (NICMOS). The Galactic core is obscured in visible light by intervening dust clouds, but infrared light penetrates the dust. The spatial resolution of this image corresponds to 0.025 light-years at the distance of the Galactic core of 26,000 light-years. Hubble reveals details in objects as small as 20 times the size of our own solar system.

The new NICMOS data show the glow from ionized hydrogen gas as well as a multitude of stars. NICMOS shows a large number of these massive stars distributed throughout the region. A new finding is that astronomers now see that the massive stars are not confined to one of the three known clusters of massive stars in the Galactic Center, known as the Central cluster, the Arches cluster, and the Quintuplet cluster. These three clusters are easily seen as tight concentrations of bright, massive stars in the NICMOS image. The distributed stars may have formed in isolation, or they may have originated in clusters that have been disrupted by strong gravitational tidal forces.

The winds and radiation from these stars form the complex structures seen in the core and in some cases they may be triggering new generations of stars. At upper left, large arcs of ionized gas are resolved into arrays of intriguingly organized linear filaments indicating a critical role of the influence of locally strong magnetic fields.

The lower left region shows pillars of gas sculpted by winds from hot massive stars in the Quintuplet cluster. At the center of the image, ionized gas surrounding the supermassive black hole at the center of the galaxy is confined to a bright spiral embedded within a circum-nuclear dusty inner-tube-shaped torus.

The false-color image was taken through a filter that reveals the glow of hot hydrogen in space.

The NICMOS mosaic required 144 Hubble orbits to make 2,304 science exposures. It was taken between February 22 and June 5, 2008.

Resembling comets streaking across the sky, these four speedy stars are plowing through regions of dense interstellar gas and creating brilliant arrowhead structures and trailing tails of glowing gas.

These bright arrowheads, or bow shocks, can be seen in these four images taken with NASA's Hubble Space Telescope. The bow shocks form when the stars' powerful stellar winds, streams of matter flowing from the stars, slam into surrounding dense gas. The phenomenon is similar to that seen when a speeding boat pushes through water on a lake.

The stars in these images are among 14 runaway stars spotted by Hubble's Advanced Camera for Surveys. The stars appear to be young, just millions of years old. Their ages are based on their colors and the presence of strong stellar winds, a signature of youthful stars.

Depending on their distance from Earth, the bullet-nosed bow shocks could be 100 billion to a trillion miles wide (the equivalent of 17 to 170 solar system diameters, measured out to Neptune's orbit). The bow shocks indicate that the stars are moving fast, more than 112,000 miles an hour (more than 180,000 kilometers an hour) with respect to the dense gas they are plowing through. They are traveling roughly five times faster than typical young stars, relative to their surroundings.

The high-speed stars have traveled far from their birth places. Assuming their youthful phase lasts only a million years and they are moving at roughly 112,000 miles an hour, the stars have journeyed 160 light-years.

The Hubble observations were taken between October 2005 and July 2006.

This pair of NASA Hubble Space Telescope pictures shows the appearance of a mysterious burst of light that was detected on February 21, 2006, brightened over 100 days, and then faded into oblivion after another 100 days. The source of the outburst remains unidentified.

The event was detected serendipitously in a Hubble search for supernovae in a distant cluster of galaxies. The light-signature of this event does not match the behavior of a supernova or any previously observed astronomical transient phenomenon in the universe.

Astronomers do not know the object's distance, so it can either be in our Milky Way galaxy or at a great astronomical distance. The optical spectrum of the object contains absorption features that have not yet been identified. This may represent a previously undetected class of transient phenomenon in the universe.

The Hubble Space Telescope has imaged striking details of the famed planetary nebula designated NGC 2818, which lies in the southern constellation of Pyxis (the Compass). The spectacular structure of the planetary nebula contains the outer layers of a star that were expelled into interstellar space.

The glowing gaseous shrouds in the nebula were shed by the central star after it ran out of fuel to sustain the nuclear reactions in its core. Our own sun will undergo a similar process, but not for another 5 billion years or so. Planetary nebulae fade gradually over tens of thousands of years. The hot, remnant stellar core of NGC 2818 will eventually cool off for billions of years as a white dwarf.

NGC 2818 is often heralded as one of the Galaxy’s few planetary nebulae to be discovered as a member of an open star cluster. The other celebrated case is the planetary nebula NGC 2438 in the open star cluster designated Messier 46. Recent investigations, however, suggest that both cases merely amount to a chance alignment, as the objects are actually located at varying distances along the line-of-sight. To date, there has yet to be a single established case of a Galactic planetary nebula discovered in an open cluster.

Planetary nebulae have been detected in several globular star clusters in our Galaxy. These densely-packed, gravitationally-bound groups of 100,000s to millions of stars are far older than their open cluster counterparts.

This Hubble image was taken in November 2008 with the Wide Field Planetary Camera 2. The colors in the image represent a range of emissions coming from the clouds of the nebula: red represents nitrogen, green represents hydrogen, and blue represents oxygen.

In 1609, Galileo improved the newly invented telescope, turned it toward the heavens, and revolutionized our view of the universe. In celebration of the 400th anniversary of this milestone, 2009 has been designated as the International Year of Astronomy.

Today, NASA's Great Observatories are continuing Galileo's legacy with stunning images and breakthrough science from the Hubble Space Telescope, the Spitzer Space Telescope, and the Chandra X-ray Observatory.

While Galileo observed the sky using visible light seen by the human eye, technology now allows us to observe in many wavelengths, including Spitzer's infrared view and Chandra's view in X-rays. Each wavelength region shows different aspects of celestial objects and often reveals new objects that could not otherwise be studied.

This image of the spiral galaxy Messier 101 is a composite of views from Spitzer, Hubble, and Chandra.

• The red color shows Spitzer's view in infrared light. It highlights the heat emitted by dust lanes in the galaxy where stars can form.

• The yellow color is Hubble's view in visible light. Most of this light comes from stars, and they trace the same spiral structure as the dust lanes.

• The blue color shows Chandra's view in X-ray light. Sources of X-rays include million-degree gas, exploded stars, and material colliding around black holes.

Such composite images allow astronomers to see how features seen in one wavelength match up with those seen in another wavelength. It's like seeing with a camera, night vision goggles, and X-ray vision all at once.

In the four centuries since Galileo, astronomy has changed dramatically. Yet our curiosity and quest for knowledge remain the same. So, too, does our wonder at the splendor of the universe.

The International Year of Astronomy Great Observatories Image Unveiling is supported by the NASA Science Mission Directorate Astrophysics Division. The project is a collaboration between the Space Telescope Science Institute, the Spitzer Science Center, and the Chandra X-ray Center.

This image of the spiral galaxy Messier 101 is a composite of views from the Spitzer Space Telescope, Hubble Space Telescope, and Chandra X-ray Observatory. Each wavelength region shows different aspects of celestial objects and often reveals new objects that could not otherwise be studied. The red color shows Spitzer's view in infrared light. It highlights the heat emitted by dust lanes in the galaxy where stars can form. The yellow color is Hubble's view in visible light. Most of this light comes from stars, and they trace the same spiral structure as the dust lanes. The blue color shows Chandra's view in X-ray light. Sources of X-rays include million-degree gas, exploded stars, and material colliding around black holes. Such composite images allow astronomers to see how features seen in one wavelength match up with those seen in another wavelength. It's like seeing with a camera, night vision goggles, and X-ray vision all at once.

The yellow color is Hubble's view in visible light. Most of this light comes from stars, and they trace the same spiral structure as the dust lanes.

The galaxy Messier 101 is a swirling spiral of stars, gas, and dust. Messier 101 is nearly twice as wide as our Milky Way Galaxy.

Spitzer's view [left frame], taken in infrared light, reveals the galaxy's delicate dust lanes as yellow-green filaments. Such dense dust clouds are where new stars can form. In this image, dust warmed by the light of hot, young stars glows red. The rest of the galaxy's hundreds of billions of stars are less prominent and form a blue haze. Astronomers can use infrared light to examine the dust clouds where stars are born.

Messier 101 has a pancake-like shape that we view face-on. This perspective shows off the spiral structure that gives it the nickname the Pinwheel Galaxy. In this Hubble image [middle frame], taken in visible light, the bright blue clumps are regions where new stars have formed. The yellowish core consists mainly of old stars. The dark brown dust lanes are colder and denser regions where interstellar clouds may collapse to form new stars. All of these features are shaped into a beautiful spiral pattern by a combination of gravity and rotation. Astronomers use visible light to study where and how stars form in spiral galaxies.

Chandra's image of Messier 101 [right frame], taken in X-ray light, shows the high- energy features of this spiral galaxy. X-rays are generally created in violent and/or high- temperature events. The white dots are X-ray sources that include the remains of exploded stars as well as material colliding at extreme speeds around black holes. The pink and blue colors are emission from million-degree gas and from clusters of massive stars. The pink emission indicates lower-energy X-rays and the blue higher-energy X- rays. One reason astronomers study Messier 101's X-rays is to better understand how black holes grow in spiral galaxies.

The International Year of Astronomy Great Observatories Image Unveiling is supported by the NASA Science Mission Directorate Astrophysics Division. The project is a collaboration between the Space Telescope Science Institute, the Spitzer Science Center, and the Chandra X-ray Center.

Messier 101 has a pancake-like shape that we view face-on. This perspective shows off the spiral structure that gives it the nickname the Pinwheel Galaxy. In this Hubble image, taken in visible light, the bright blue clumps are regions where new stars have formed. The yellowish core consists mainly of old stars. The dark brown dust lanes are colder and denser regions where interstellar clouds may collapse to form new stars. All of these features are shaped into a beautiful spiral pattern by a combination of gravity and rotation. Astronomers use visible light to study where and how stars form in spiral galaxies.

Messier 101 (also known as NGC 5457) is a stunning face-on spiral galaxy about 22 million light-years away in the direction of the constellation Ursa Major. Hubble's visible-light view shows off luminous swirling spirals of bright stars and glowing gas that give M101 a classic spiral look. It is no wonder it has been dubbed the "Pinwheel Galaxy."

This galaxy is similar to our own Milky Way galaxy, except M101 is nearly twice the size. The section of M101 shown here is 22,500 light-years across, while the entire galaxy is on the order of 114,000 light-years across.

In this unique black and white Hubble Space Telescope image, bright knots of glowing gas highlight regions of active star formation. These star forming regions are concentrated in M101's spiral arms along with brilliant clusters of hot, newborn stars. The softer, less-bright areas near the core and between the arms consist mainly of old stars. The dark dust lanes, also visible in the image, are colder and denser regions where interstellar clouds may collapse to form new stars.

This image was made using Hubble archival data taken with the Advanced Camera for Surveys in 2002-2004. The image is a combination of two types of data: images taken with broad band blue, visible, and infrared filters show the stars while the glowing hydrogen gas is revealed in a narrow band filter designed especially for that purpose. The combination of different types of observations taken at multiple wavelengths is essential to the complete understanding of any celestial object.

This is a Hubble Space Telescope photo of the spiral galaxy NGC 3021. This was one of several hosts of recent Type Ia supernovae observed by astronomers to refine the measure of the universe's expansion rate, called the Hubble constant. Hubble made precise measurements of Cepheid variable stars in the galaxy, highlighted by green circles in the four inset boxes. These stars pulsate at a rate that is matched closely to their intrinsic brightness. This makes them ideal for measuring intergalactic distances. The Cepheids are used to calibrate an even brighter milepost marker that can be used over greater distances, a Type Ia supernova. The supernova was observed in the galaxy in 1995. The images in the boxes were taken with the Near Infrared Camera and Multi-Object Spectrometer (NICMOS).

This NASA Hubble Space Telescope image shows three galaxies playing a game of gravitational tug-of-war that may result in the eventual demise of one of them.

Located about 100 million light-years away in the constellation Piscis Austrinus (the Southern Fish), the galaxy interaction may ultimately lead to the three reforming into two larger star cities.

The three galaxies—NGC 7173 (middle left), NGC 7174 (middle right), and NGC 7176 (lower right)—are part of Hickson Compact Group 90, named after astronomer Paul Hickson, who first cataloged these small clusters of galaxies in the 1980s. NGC 7173 and NGC 7176 appear to be smooth, normal elliptical galaxies without much gas and dust.

In stark contrast, NGC 7174 is a mangled spiral galaxy that appears as though it is being ripped apart by its close neighbors. The galaxies are experiencing a strong gravitational interaction, and as a result, a significant number of stars have been ripped away from their home galaxies. These stars are now spread out, forming a tenuous luminous component in the galaxy group.

Ultimately, astronomers believe that NGC 7174 will be shredded and only the two "normal" elliptical galaxies (NGC 7173 and NGC 7176) will remain.

Hubble imaged these galaxies with the Advanced Camera for Surveys in May 2006.

For additional information, contact:

Colleen Sharkey
Hubble/ESA, Garching, Germany
011-49-89-3200-6306
011-49-015115373591 (cell)
csharkey@eso.org

Ray Villard
Space Telescope Science Institute, Baltimore, Md.
410-338-4514
villard@stsci.edu

These four dwarf galaxies are part of a census of small galaxies in the tumultuous heart of the nearby Perseus galaxy cluster.

The galaxies appear smooth and symmetrical, suggesting that they have not been tidally disrupted by the pull of gravity in the dense cluster environment. Larger galaxies around them, however, are being ripped apart by the gravitational tug of other galaxies.

The images, taken by NASA's Hubble Space Telescope, are evidence that the undisturbed galaxies are enshrouded by a "cushion" of dark matter, which protects them from their rough-and-tumble neighborhood.

Dark matter is an invisible form of matter that accounts for most of the universe's mass. Astronomers have deduced the existence of dark matter by observing its gravitational influence on normal matter, consisting of stars, gas, and dust.

Observations by Hubble's Advanced Camera for Surveys spotted 29 dwarf elliptical galaxies in the Perseus Cluster, located 250 million light-years away and one of the closest galaxy clusters to Earth. Of those galaxies, 17 are new discoveries.

The images were taken in 2005.

On February 24, 2009, the Hubble Space Telescope took a photo of four moons of Saturn passing in front of their parent planet. In this view, the giant orange moon Titan casts a large shadow onto Saturn's north polar hood. Below Titan, near the ring plane and to the left is the moon Mimas, casting a much smaller shadow onto Saturn's equatorial cloud tops. Farther to the left, and off Saturn's disk, are the bright moon Dione and the fainter moon Enceladus.

These rare moon transits only happen when the tilt of Saturn's ring plane is nearly "edge on" as seen from the Earth. Saturn's rings will be perfectly edge on to our line of sight on August 10, 2009, and September 4, 2009. Unfortunately, Saturn will be too close to the sun to be seen by viewers on Earth at that time. This "ring plane crossing" occurs every 14-15 years. In 1995-96 Hubble witnessed the ring plane crossing event, as well as many moon transits, and even helped discover several new moons of Saturn.

The banded structure in Saturn's atmosphere is similar to Jupiter's.

Early 2009 was a favorable time for viewers with small telescopes to watch moon and shadow transits crossing the face of Saturn. Titan, Saturn's largest moon, crossed Saturn on four separate occasions: January 24, February 9, February 24, and March 12, although not all events were visible from all locations on Earth.

These pictures were taken with Hubble's Wide Field Planetary Camera 2 on February 24, 2009, when Saturn was at a distance of roughly 775 million miles (1.25 billion kilometers) from Earth. Hubble can see details as small as 190 miles (300 km) across on Saturn. The dark band running across the face of the planet slightly above the rings is the shadow of the rings cast on the planet.

This sequence of images captures the parade of several of Saturn's moons transiting the face of the gas giant planet. This is a rare event because the rings are tilted edge on to Earth every 15 years. The top frame captures the giant moon Titan and its shadow near Saturn's northern polar hood. Tiny Mimas and its shadow have just entered the left limb of Saturn, slightly above the rings. To the far left off the disk, Dione, the brightest of the icy moons in this view – and Enceladus, fainter and farther to the left – can easily be seen just above the rings. In the center frame, Dione and Enceladus can be seen near the western limb of Saturn, while Titan's shadow is off the limb, and Mimas is on the right most limb, its shadow also now off the limb. In the bottom frame, Dione and its shadow are centered above Enceladus and its shadow. Titan is now off the right limb. This picture sequence was taken with Hubble's Wide Field Planetary Camera 2 on February 24, 2009, when Saturn was at a distance of roughly 775 million miles (1.25 billion kilometers) from Earth. Hubble can see details as small as 190 miles (300 km) across on Saturn.

This close-up view of Saturn's disk captures the transit of several moons across the face of the gas giant planet. The giant orange moon Titan – larger than the planet Mercury – can be seen at upper right. The white icy moons that are much closer to Saturn, hence much closer to the ring plane in this view, are, from left to right: Enceladus, Dione, and Mimas. The dark band running across the face of the planet slightly above the rings is the shadow of the rings cast on the planet. This picture was taken with Hubble's Wide Field Planetary Camera 2 on February 24, 2009, when Saturn was at a distance of roughly 775 million miles (1.25 billion kilometers) from Earth. Hubble can see details as small as 190 miles (300 km) across on Saturn.

Archival photographs from NASA's Hubble Space Telescope have been used to uncover the progenitor star to a supernova that exploded in 2005. To the surprise of astronomers, the progenitor is a rare class of ultra-bright star that, according to theory, shouldn't explode so early in its evolution.

[Top Center] This is a 2005 ground-based photograph of the supernova as seen in host galaxy NGC 266, located in the constellation Pisces.

Credit: Puckett Observatory

[Bottom Left] This is a 1997 Hubble archival visible-light image of the region of the galaxy where the supernova exploded. The white circle marks a star that Hubble measured to have an absolute magnitude of -10.3. This corresponds to the brightness of 1 million suns (at the galaxy's distance of 215 million light-years).

Credit: NASA, ESA, and A. Gal-Yam (Weizmann Institute of Science, Israel)

[Bottom Center] This is a near-infrared-light photo of the supernova explosion taken on Nov. 11, 2005, with the Keck telescope, using adaptive optics. The blast is centered on the position of the progenitor.

Credit: NASA, ESA, and A. Gal-Yam (Weizmann Institute of Science, Israel), D. Leonard (San Diego State University), and D. Fox (Penn State University)

[Bottom Right] This is a visible-light Hubble follow-up image taken on September 26, 2007. Note that a bright source near the site of the supernova can be seen in all three panels, but the progenitor star is gone. The Hubble pictures from both epochs were taken with the Wide Field Planetary Camera 2.

Credit: NASA, ESA, and A. Gal-Yam (Weizmann Institute of Science, Israel)

On April 1-2, the Hubble Space Telescope photographed the winning target in the Space Telescope Science Institute's "You Decide" competition in celebration of the International Year of Astronomy (IYA).

The winner is a group of galaxies called Arp 274. The striking object received 67,021 votes out of the nearly 140,000 votes cast for the six candidate targets.

Arp 274, also known as NGC 5679, is a system of three galaxies that appear to be partially overlapping in the image, although they may be at somewhat different distances. The spiral shapes of two of these galaxies appear mostly intact. The third galaxy (to the far left) is more compact, but shows evidence of star formation.

Two of the three galaxies are forming new stars at a high rate. This is evident in the bright blue knots of star formation that are strung along the arms of the galaxy on the right and along the small galaxy on the left.

The largest component is located in the middle of the three. It appears as a spiral galaxy, which may be barred. The entire system resides at about 400 million light-years away from Earth in the constellation Virgo.

Hubble's Wide Field Planetary Camera 2 was used to image Arp 274. Blue, visible, and infrared filters were combined with a filter that isolates hydrogen emission. The colors in this image reflect the intrinsic color of the different stellar populations that make up the galaxies. Yellowish older stars can be seen in the central bulge of each galaxy. A bright central cluster of stars pinpoint each nucleus. Younger blue stars trace the spiral arms, along with pinkish nebulae that are illuminated by new star formation. Interstellar dust is silhouetted against the starry population. A pair of foreground stars inside our own Milky Way are at far right.

The International Year of Astronomy is the celebration of the 400th anniversary of Galileo's first observations with a telescope. People around the world are coming together to participate in the IYA's 100 Hours of Astronomy, April 2 to 5. This global astronomy event is geared toward encouraging as many people as possible to experience the night sky.

For additional information, contact:

Ray Villard
Space Telescope Science Institute, Baltimore, Md.
410-338-4514
villard@stsci.edu

Mario Livio
Space Telescope Science Institute, Baltimore, Md.
410-338-4439
mlivio@stsci.edu

Keith Noll
Space Telescope Science Institute, Baltimore, Md.
410-338-1828
noll@stsci.edu

This is a Hubble Space Telescope NICMOS (Near Infrared Camera and Multi-Object Spectrometer) coronagraphic image of a planet orbiting the star HR 8799, located 130 light-years away.

The coronagraph has been used to block the light from the bright star (black circle) allowing the search for the dim glow of the planet HR 8799b. A special image-processing algorithm was used to suppress the starlight bleeding around the coronagraph to the point where the planet was detectable.

The planet was first discovered in 2007 at the Gemini North observatory. It was identified in the NICMOS archival data in a follow-up search to see if Hubble had serendipitously imaged the planet. The planet changed position between the two epochs as it moved along its centuries-long orbit about the star.

The planet is estimated to be at least seven times the mass of Jupiter and about the same diameter. It is located 6.3 billion miles from its parent star.

These images taken in ultraviolet light by NASA's Hubble Space Telescope reveal the brightening of a jet of gas blasting from the core of the gigantic elliptical galaxy M87. M87 is located 54 million light-years away in the Virgo Cluster.

The flare-up is coming from a knot of hot gas, called HST-1, embedded in the jet. The jet is powered by accretion onto a supermassive black hole, one of the most massive black holes yet discovered.

Hubble's Space Telescope Imaging Spectrograph (STIS) snapped the top row of images and Hubble's Advanced Camera for Surveys (ACS) the bottom row. The core of M87 is located at lower left in the images. HST-1 is the bright blob at center. The glowing material at far right is part of a stream of particles in the jet that speed up and glow in the ultraviolet.

The Hubble images, obtained from the Hubble archive, show the jet growing brighter over a seven-year period, eventually outshining even the luminous core of M87. The ACS image taken on May 9, 2005, reveals that HST-1 has become brighter than M87's core. HST-1 is 214 light-years from the core.

Hubble's crisp vision gives astronomers a clear view of the brightening knot. The telescope resolves HST-1 and separates it from the galaxy's core.

This composite image shows the massive galaxy cluster MACS J0717.5+3745 (MACS J0717, for short), where four separate galaxy clusters have been involved in a collision — the first time such a phenomenon has been documented. Hot gas is shown in an image from NASA's Chandra X-ray Observatory, and galaxies are shown in an optical image from NASA's Hubble Space Telescope. The hot gas is color-coded to show temperature, where the coolest gas is reddish purple, the hottest gas is blue, and the temperatures in between are purple.

The repeated collisions in MACS J0717 are caused by a 13-million-light-year-long stream of galaxies, gas, and dark matter — known as a filament — pouring into a region already full of matter. A collision between the gas in two or more clusters causes the hot gas to slow down. However, the massive and compact galaxies do not slow down as much as the gas does, and so move ahead of it. Therefore, the speed and direction of each cluster's motion — perpendicular to the line of sight — can be estimated by studying the offset between the average position of the galaxies and the peak in the hot gas.

MACS J0717 is located about 5.4 billion light-years from Earth. It is one of the most complex galaxy clusters ever seen. Other well-known clusters, like the Bullet Cluster and MACS J0025.4-1222, involve the collision of only two galaxy clusters and show much simpler geometry.

To commemorate the Hubble Space Telescope's 19 years of historic, trailblazing science, the orbiting telescope has photographed a peculiar system of galaxies known as Arp 194. This interacting group contains several galaxies, along with a "cosmic fountain" of stars, gas, and dust that stretches over 100,000 light-years.

The northern (upper) component of Arp 194 appears as a haphazard collection of dusty spiral arms, bright blue star-forming regions, and at least two galaxy nuclei that appear to be connected and in the early stages of merging. A third, relatively normal, spiral galaxy appears off to the right. The southern (lower) component of the galaxy group contains a single large spiral galaxy with its own blue star-forming regions.

However, the most striking feature of this galaxy troupe is the impressive blue stream of material extending from the northern component. This "fountain" contains complexes of super star clusters, each one of which may contain dozens of individual young star clusters. The blue color is produced by the hot, massive stars which dominate the light in each cluster. Overall, the "fountain" contains many millions of stars.

These young star clusters probably formed as a result of the interactions between the galaxies in the northern component of Arp 194. The compression of gas involved in galaxy interactions can enhance the star-formation rate and give rise to brilliant bursts of star formation in merging systems.

Hubble's resolution shows clearly that the stream of material lies in front of the southern component of Arp 194, as evidenced by the dust that is silhouetted around the star-cluster complexes. It is therefore not entirely clear whether the southern component actually interacts with the northern pair.

The details of the interactions among the multiple galaxies that make up Arp 194 are complex. The shapes of all the galaxies involved appear to have been distorted, possibly by their gravitational interactions with one another.

Arp 194, located in the constellation Ursa Major, resides approximately 600 million light-years away from Earth. It contains some of the many interacting and merging galaxies known in our relatively nearby universe. These observations were taken in January of 2009 with the Wide Field Planetary Camera 2. Images taken through blue, green, and red filters were combined to form this picturesque image of galaxy interaction.

For additional information, contact:

Ray Villard
Space Telescope Science Institute, Baltimore, Md.
410-338-4514
villard@stsci.edu

Keith Noll
Space Telescope Science Institute, Baltimore, Md.
410-338-1828
noll@stsci.edu

This composite image shows the galaxy cluster 1E 0657-556, also known as the "bullet cluster." This cluster was formed after the collision of two large clusters of galaxies, the most energetic event known in the universe since the Big Bang.

Hot gas detected by Chandra in X-rays is seen as two pink clumps in the image and contains most of the "normal," or baryonic, matter in the two clusters. The bullet-shaped clump on the right is the hot gas from one cluster, which passed through the hot gas from the other larger cluster during the collision. An optical image from Magellan and the Hubble Space Telescope shows the galaxies in orange and white. The blue areas in this image depict where astronomers find most of the mass in the clusters. The concentration of mass is determined by analyzing the effect of so-called gravitational lensing, where light from the distant objects is distorted by intervening matter. Most of the matter in the clusters (blue) is clearly separate from the normal matter (pink), giving direct evidence that nearly all of the matter in the clusters is dark.

The hot gas in each cluster was slowed by a drag force, similar to air resistance, during the collision. In contrast, the dark matter was not slowed by the impact because it does not interact directly with itself or the gas except through gravity. Therefore, during the collision the dark matter clumps from the two clusters moved ahead of the hot gas, producing the separation of the dark and normal matter seen in the image. If hot gas was the most massive component in the clusters, as proposed by alternative theories of gravity, such an effect would not be seen. Instead, this result shows that dark matter is required.

Comparing the optical image with the blue emission shows that the most of the galaxies in each cluster are located near the two dark matter clumps. This shows that the galaxies in each cluster did not slow down because of the collision, unlike the hot gas.

This image, taken with the Advanced Camera for Surveys aboard NASA's Hubble Space Telescope, shows the newly discovered planet, Fomalhaut b, orbiting its parent star, Fomalhaut.

The small white box at lower right pinpoints the planet's location. Fomalhaut b has carved a path along the inner edge of a vast, dusty debris ring encircling Fomalhaut that is 21.5 billion miles across. Fomalhaut b lies 1.8 billion miles inside the ring's inner edge and orbits 10.7 billion miles from its star.

The inset at bottom right is a composite image showing the planet's position during Hubble observations taken in 2004 and 2006. Astronomers have calculated that Fomalhaut b completes an orbit around its parent star every 872 years.

The white dot in the center of the image marks the star's location. The region around Fomalhaut's location is black because astronomers used the Advanced Camera's coronagraph to block out the star's bright glare so that the dim planet could be seen. Fomalhaut b is 1 billion times fainter than its star. The radial streaks are scattered starlight. The red dot at lower left is a background star.

The Fomalhaut system is 25 light-years away in the constellation Piscis Australis.

This false-color image was taken in October 2004 and July 2006.

These postage-stamp-size images reveal 36 young galaxies caught in the act of merging with other galaxies. These galaxies appear as they existed many billions of years ago. Astronomers have dubbed them "tadpole galaxies" because of their distinct knot-and-tail shapes, which suggest that they are engaging in galactic mergers.

The galaxies were captured in 2004 in the Hubble Space Telescope's Ultra Deep Field (HUDF) survey of thousands of distant galaxies. They are part of more than 165 tadpole galaxies in the HUDF studied recently by a team of astronomers. The team was looking for indications of black hole activity in these young galaxies. A characteristic signature of such activity is a fluctuation in brightness over time, an indication that a black hole is feasting on surrounding stars and gas. The flickering light does not come from the black hole itself but from the area immediately surrounding the black hole. Astronomers did not see brightness fluctuations in any of the tadpole galaxies they surveyed. They did, however, observe the fluctuations in 46 different faint galaxies in the HUDF. These galaxies existed millions of years after the tadpole galaxies. This result suggests that black holes did not begin eating when galaxies merged. Rather, it took several hundred million years for the gas and stars from the merger to arrive on the black hole's dinner plate and become visible as flickering light. This finding agrees with recent computer models which predicted that the feeding habits of black holes would become visible after galactic mergers.

Each postage-stamp image is roughly 84,000 light-years on a side, which is about the size of our Milky Way Galaxy today. The tadpole galaxies are shown in the middle of each image and are considerably smaller than today's giant galaxies. The image was taken by Hubble's Advanced Camera for Surveys.

This is a sampling of the host galaxies of long-duration gamma-ray bursts taken by NASA's Hubble Space Telescope. Gamma-ray bursts are powerful flashes of high-energy radiation that arise from some supernovae, the explosive deaths of extremely massive stars. Long-duration bursts last more than one to two seconds.

The green crosshairs pinpoint the location of the gamma-ray bursts, now long faded away. The galaxies in these images were part of a study that compared the environments of long bursts with those of supernovae. Only a small fraction of a certain type of supernovae produces gamma-ray bursts.

These six images show the wide variety of host galaxies of gamma-ray bursts. The distances of these bursts range from 2 billion to 10 billion light-years from Earth. Most of the galaxies in these images are misshapen, irregular galaxies. The only exception is the spiral galaxy in the middle image on the top row. In this image, the bright round objects above, below, and to the right of the cross hairs are foreground stars in the Small Magellanic Cloud, a satellite galaxy of our Milky Way Galaxy.

Researchers conducting the study found that long bursts occur in the brightest regions of mostly irregular galaxies where the most massive stars are forming. Typical supernovae, on the other hand, are more uniformly distributed across their host galaxies. Supernovae also come from larger, more developed galaxies than do the gamma-ray bursts.

The images were taken between 1999 and 2005 by Hubble's Wide Field Planetary Camera 2, Space Telescope Imaging Spectrograph, and Advanced Camera for Surveys.

The team that made the study consists of A. Fruchter (Space Telescope Science Institute, or STScI); A. Levan (STScI/University of Leicester/University of Hertfordshire); L. Strolger (STScI/Western Kentucky University); P. Vreeswijk (European Southern Observatory, Chile); S.Thorsett (University of California, Santa Cruz); D. Bersier (STScI/Astrophysics Research Institute/Liverpool John Moores University); I. Burud (STScI/Norwegian Meteorological Institute, Copenhagen); J. Castro Ceron (STScI/Niels Bohr Institute/University of Copenhagen); A. Castro-Tirado (Instituto de Astrofisica de Andalucia, Spain); C. Conselice (California Institute of Technology/University of Nottingham); T. Dahlen (Stockholm University); H. Ferguson (STScI); J. Fynbo (Niels Bohr Institute/University of Copenhagen); P. Garnavich (University of Notre Dame); R. Gibbons (STScI/Vanderbilt University); J. Gorosabel (STScI/Instituto de Astrofisica de Andalucia, Spain); T. Gull (NASA/GSFC); J. Hjorth (Niels Bohr Institute/University of Copenhagen); S. Holland (NASA/GSFC); C. Kouveliotou (NASA/MSFC); Z. Levay and M. Livio (STScI); M.R. Metzger (Renaissance Technologies Corporation, New York); P. Nugent (Lawrence Berkeley National Laboratory); L. Petro (STScI); E. Pian (INAF, Osservatorio Astronomico di Trieste, Italy); J. Rhoads, A. Riess, and K. Sahu (STScI); A. Smette (European Southern Observatory, Chile); N. Tanvir (University of Hertfordshire); R. Wijers (University of Amsterdam); and S. Woosley (University of California, Santa Cruz)

Two decades ago, astronomers spotted one of the brightest exploding stars in more than 400 years.

Since that first sighting, the doomed star, called Supernova 1987A, has continued to fascinate astronomers with its spectacular light show. NASA's Hubble Space Telescope is one of many observatories that has been monitoring the blast's aftermath.

This image shows the entire region around the supernova. The most prominent feature in the image is a ring with dozens of bright spots. A shock wave of material unleashed by the stellar blast is slamming into regions along the ring's inner regions, heating them up, and causing them to glow. The ring, about a light-year across, was probably shed by the star about 20,000 years before it exploded.

Astronomers detected the first bright spot in 1997, but now they see dozens of spots around the ring. Only Hubble can see the individual bright spots. In the next few years, the entire ring will be ablaze as it absorbs the full force of the crash. The glowing ring is expected to become bright enough to illuminate the star's surroundings, providing astronomers with new information on how the star expelled material before the explosion.

The pink object in the center of the ring is debris from the supernova blast. The glowing debris is being heated by radioactive elements, principally titanium 44, created in the explosion. The debris will continue to glow for many decades.

The origin of a pair of faint outer red rings, located above and below the doomed star, is a mystery. The two bright objects that look like car headlights are a pair of stars in the Large Magellanic Cloud. The supernova is located 163,000 light-years away in the Large Magellanic Cloud.

The image was taken in December 2006 with Hubble's Advanced Camera for Surveys.

This image shows the quasar HE0450-2958 after advanced image processing known as MCS-deconvolution. Thanks to this technique, it is possible to remove the brilliant glare from the quasar itself.

The most interesting feature in the image is the nearly total absence of starlight from a host galaxy. The processing also reveals an interesting smaller cloud of gas about 2,500 light-years wide, which the scientists call "the blob," just next to the quasar. Very Large Telescope (VLT) observations show this cloud to be glowing because it is bathed in the intense radiation coming from the quasar. Most likely, it is the gas from this ‘blob' that feeds the supermassive black hole, thereby allowing it to shine as a quasar.

This is a composite photo, assembled from separate images of Jupiter and Comet P/Shoemaker-Levy 9, as imaged by the Wide Field & Planetary Camera 2 (WFPC2), aboard. NASA's Hubble Space Telescope (HST).

Jupiter was imaged on May 18, 1 994, when the giant planet was at a distance of 420 million miles (670 million km) from Earth. This "true-color" picture was assembled from separate HST exposures in red, blue, and green light. Jupiter's rotation between exposures creates the blue and red fringe on either side of the disk. HST can resolve details in Jupiter's magnificent cloud belts and zones as small as 200 miles (320 km) across (wide field mode). This detailed view is only surpassed by images from spacecraft that have traveled to Jupiter.

The dark spot on the disk of Jupiter is the shadow of the inner moon lo. This volcanic moon appears as an orange and yellow disk just to the upper right of the shadow. Though lo is approximately the size of Earth's Moon (but 2,000 times farther away), HST can resolve surface details.

When the comet was observed on May 17, its train of 21 icy fragments stretched across 710 thousand miles (1.1 million km) of space, or 3 times the distance between Earth and the Moon This required six WFPC exposures along the comet train to include all the nuclei. The image was taken in red light.

The apparent angular size of Jupiter relative to the comet, and its angular separation from the comet when the images were taken, have been modified for illustration purposes.

A pair of small moons that NASA's Hubble Space Telescope discovered orbiting Pluto now have official names: Nix and Hydra. Photographed by Hubble in 2005, Nix and Hydra are roughly 5,000 times fainter than Pluto and are about two to three times farther from Pluto than its large moon, Charon, which was discovered in 1978.

These images, taken by NASA's Hubble Space Telescope, show myriad stars residing in the central regions of the three dwarf galaxies NGC 4163, NGC 4068, and IC 4662.

The bluish dots are younger stars; the reddish dots, older stars. The irregularly shaped red blobs in the images of NGC 4163 and IC 4662 are regions of current starburst activity. Starbursts are areas of intense star formation.

The three galaxies are part of a Hubble study of starbursts in nearby, small, or dwarf, galaxies. Based on this study, astronomers have found that starbursts continue 100 times longer than first thought, lasting 200 million to 400 million years. These galaxies show that starbursts are not isolated events, but sweep across a galaxy.

Each of the three starburst galaxies has a different shape. The collection of stars in NGC 4163 is more spherical, with a higher concentration of stars forming in the center. By contrast, the grouping of stars in NGC 4068 is more elongated and has fewer new stars than the other two galaxies. Astronomers think the starburst in this galaxy is ending. In the image of IC 4662 the clumpy red blobs peppered throughout the galaxy indicate active regions of star birth. One such region extends off the image's top, right edge. This galaxy exhibits the strongest star formation of the three galaxies in the study.

The distances of the galaxies range from 8 million to 14 million light-years away.

The images were taken in 2004 by the Advanced Camera for Surveys.

The Hubble community bids farewell to the soon-to-be decommissioned Wide Field Planetary Camera 2 (WFPC2) onboard the Hubble Space Telescope. In tribute to Hubble's longest-running optical camera, a planetary nebula has been imaged as WFPC2's final "pretty picture."

This planetary nebula is known as Kohoutek 4-55 (or K 4-55). It is one of a series of planetary nebulae that were named after their discoverer, Czech astronomer Lubos Kohoutek. A planetary nebula contains the outer layers of a red giant star that were expelled into interstellar space when the star was in the late stages of its life. Ultraviolet radiation emitted from the remaining hot core of the star ionizes the ejected gas shells, causing them to glow.

In the specific case of K 4-55, a bright inner ring is surrounded by a bipolar structure. The entire system is then surrounded by a faint red halo, seen in the emission by nitrogen gas. This multi-shell structure is fairly uncommon in planetary nebulae.

This Hubble image was taken by WFPC2 on May 4, 2009. The colors represent the makeup of the various emission clouds in the nebula: red represents nitrogen, green represents hydrogen, and blue represents oxygen. K 4-55 is nearly 4,600 light-years away in the constellation Cygnus.

The WFPC2 instrument, which was installed in 1993 to replace the original Wide Field/Planetary Camera, will be removed to make room for Wide Field Camera 3 during the upcoming Hubble Servicing Mission.

During the camera's amazing, nearly 16-year run, WFPC2 provided outstanding science and spectacular images of the cosmos. Some of its best-remembered images are of the Eagle Nebula pillars, Comet P/Shoemaker-Levy 9's impacts on Jupiter's atmosphere, and the 1995 Hubble Deep Field — the longest and deepest Hubble optical image of its time.

The scientific and inspirational legacy of WFPC2 will be felt by astronomers and the public alike, for as long as the story of the Hubble Space Telescope is told.

WFPC2 was developed and built by NASA's Jet Propulsion Laboratory, Pasadena, Calif.

This Hubble picture, taken on July 23, is the sharpest visible-light picture taken of the impact feature. The observations were made with Hubble's new camera, the Wide Field Camera 3 (WFC3).

The combination of the Hubble data with mid-infrared images from ground-based telescopes will give astronomers an insight into changes of the vertical structure of Jupiter's atmosphere due to the impact. The expanding spot is twice the length of the United States.

First discovered by Australian amateur astronomer Anthony Wesley, the feature is the impact site and "backsplash" of material from a small object that plunged into Jupiter's atmosphere and disintegrated.

The only other time in history such a feature has been seen on Jupiter was in 1994 during the collision of fragments from comet Shoemaker-Levy 9. The spot looks strikingly similar to comet Shoemaker-Levy 9's impact features. The details seen in the Hubble view shows lumpiness in the debris plume caused by turbulence in Jupiter's atmosphere.

The impactor is estimated to be the size of several football fields. The force of the explosion on Jupiter was thousands of times more powerful than the suspected comet or asteroid that exploded in June 1908 over the Tunguska River Valley in Siberia.

This is a natural color image of Jupiter as seen in visible light.

Closeup view of the new dark spot on Jupiter taken with Hubble's Wide Field Camera 3 on July 23, 2009.

WFC3 image of Jupiter taken July 23, 2009.

This illustration compares the Milky Way with a compact galaxy in the early universe.

Looking almost 11 billion years into the past, astronomers have measured the motions of stars for the first time in a very distant galaxy. They are whirling at a speed of one million miles per hour—about twice the speed of our Sun through the Milky Way. The galaxies are a fraction the size of our Milky Way, and so may have evolved over billions of years into the full-grown galaxies seen around us today.

These four images are among the first observations made by the new Wide Field Camera 3 aboard the upgraded NASA Hubble Space Telescope.

The image at top left shows NGC 6302, a butterfly-shaped nebula surrounding a dying star. At top right is a picture of a clash among members of a galactic grouping called Stephan's Quintet. The image at bottom left gives viewers a panoramic portrait of a colorful assortment of 100,000 stars residing in the crowded core of Omega Centauri, a giant globular cluster. At bottom right, an eerie pillar of star birth in the Carina Nebula rises from a sea of greenish-colored clouds.

The wispy, glowing, magenta structures in this NASA Hubble Space Telescope image are the remains of a star 10 to 15 times the mass of the Sun that we would have seen exploding as a supernova 3,000 years ago. The remnant's fast-moving gas is plowing into the surrounding gas of the galaxy, creating a supersonic shock wave in the surrounding medium and making the material glow.

The Hubble visible-light image reveals, deep within the remnant, a crescent-shaped cloud of pink emission from hydrogen gas and soft purple wisps that correspond to regions of glowing oxygen. A dense background of colorful stars is also visible.

Probing this tattered gaseous relic, the newly installed Cosmic Origins Spectrograph (COS) aboard NASA's Hubble Space Telescope detected pristine gas ejected by the doomed star that has not yet mixed with the gas in the interstellar medium. The supernova remnant, called N132D, resides in the Large Magellanic Cloud, a small companion galaxy of the Milky Way located 170,000 light-years away. The resulting spectrum, taken in ultraviolet light, shows glowing oxygen and carbon in the remnant.

These results allow astronomers to better understand why some stars form an abundance of certain elements, like oxygen, but not others.

Ultraviolet light is blocked by the Earth's atmosphere, so the observation of N132D in the ultraviolet requires the use of the space-borne Hubble telescope. The broadest range of spectral signatures of the glowing gas appear in the ultraviolet, allowing astronomers to determine the quantities, or abundances, of key elements such as oxygen, as well as elements whose abundances cannot be traced from visible-light images, including carbon, magnesium, and silicon.

Previous ultraviolet instruments on Hubble were not sensitive enough to distinguish between the unmixed ejecta and the "shocked" gas of the surrounding interstellar medium.

Supernova remnants provide a rare opportunity to search for the material hidden deep inside a star. This in turn yields information on how stars evolve and how they manufacture chemicals in their interiors. Supernova explosions also enrich the interstellar medium with new chemical elements, which are incorporated into future generations of stars.

The COS observations were made on August 10, 2009. COS was installed by NASA astronauts in May 2009, during the servicing mission to upgrade and repair the 19-year-old Hubble telescope.

The visible-light image was taken on August 2, 2009, with Hubble's new Wide Field Camera 3 (WFC3). A filter that isolates emission from sulfur was combined with archival data from the Advanced Camera for Surveys (ACS). The ACS data include color filters that sample starlight in the blue, green, and red portions of the spectrum, as well as the pink emission from glowing hydrogen gas.

These Hubble observations of N132D are part of the Hubble Servicing Mission 4 Early Release Observations.

Supernova remnant N132D in the Large Magellanic Cloud

Spectrum of the supernova remnant LMC N132D taken with Hubble's Cosmic Origins Spectrograph.

Rings of brilliant blue stars encircle the bright, active core of this spiral galaxy, whose monster black hole is blasting material into space at 9 million miles an hour.

Viewed nearly face-on, the galaxy, called Markarian 817, shows intense star-forming regions and dark bands of interstellar dust along its spiral arms.

Observations by the new Cosmic Origins Spectrograph (COS) aboard NASA's Hubble Space Telescope captured the powerful outflow of material from this galaxy.

The COS spectrum of Markarian 817 highlights the outflow's dynamic nature. A gas cloud containing hydrogen gas that was detected in Hubble data taken in 1997 does not appear in the COS observation because the cloud has apparently been driven out by an outflow of material from the galaxy.

This discharge is being powered by a huge disk of matter encircling the supermassive black hole, which is 40 million times more massive than our Sun. The disk is driving the material out of the galaxy through powerful winds, produced by streams of charged particles. Some of the outflow rains back onto the galaxy. The rest settles into the intergalactic gas.

Astronomers want to know how much of the outflow lands in the galaxy and how much escapes into intergalactic space. To achieve this, astronomers need high-quality spectroscopic observations to detect the signatures of the outflowing material, which includes carbon, nitrogen, and oxygen. This will allow them to determine the composition, location, and dynamics of the winds that distribute the material.

Markarian 817 is 430 million light-years away in the northern constellation Draco. COS observed the galaxy on August 4, 2009, using its far-ultraviolet detector to distinguish the outflow from the galaxy's core. NASA astronauts installed COS during a servicing mission in May to upgrade and repair the 19-year-old Hubble telescope.

The Hubble image was taken with Hubble's Wide Field Camera 3 on August 2, 2009. The composite image was made by using filters that isolate light from the blue, green, and infrared portions of the spectrum, as well as emission from glowing hydrogen.

The Hubble observations are part of the Hubble Servicing Mission 4 Early Release Observations.

Active galaxy Markarian 817

Comparison of Markarian 817 spectra taken with the COS detector in 2009 and GHRS detector in 1997

Using a distant quasar as a cosmic flashlight, a new instrument aboard NASA's Hubble Space Telescope has begun probing the invisible, skeletal structure of the universe.

Called the cosmic web, it is the diffuse, faint gas located in the space between galaxies. More than half of all normal matter resides outside of galaxies. By observing the cosmic web, astronomers can probe the raw materials from which galaxies form, and determine how this gas was assembled into the complex structures of the present-day universe.

Using the light from the quasar PKS 0405-123, located 7 billion to 8 billion light-years away, the newly installed Cosmic Origins Spectrograph (COS) on Hubble probed a string of gas clouds residing along the light path at different distances. Quasars are the bright cores of active galaxies and are powered by supermassive black holes. Thousands of quasars have been observed, all at extreme distances from our Milky Way galaxy. The most luminous quasars radiate at a rate equivalent to a trillion suns.

The COS spectrum shown here reveals the absorption lines of elements that make up the intervening gas clouds traversed by the quasar's light. COS detected three to five times more lower-density filaments of hydrogen in the cosmic web than were seen in previous observations along this line of sight. The instrument also detected evidence of glowing oxygen and nitrogen that predominantly trace strong shocks in the filamentary cosmic web.

These shocks are produced by gravitational interactions between intergalactic clouds of gas falling onto filaments in the web and by the fast outflow of material from star-forming galaxies.

COS produced this spectrum and detected many previously unseen filaments in only a quarter of the time it took to produce spectra in previous studies of this object (using earlier instruments). The spectrum is also of higher quality (with a better signal-to-noise ratio) than those spectra produced by the best previous observations.

With the COS, astronomers have access to thousands of quasars where only a handful could be observed before in the ultraviolet. Each quasar sightline passes through multiple filaments of the cosmic web, providing a picture of how intergalactic spaces evolve over time, as light passes from the quasar to us.

These data are the first in a series of large observation programs that will map out the cosmic web. The studies will trace the complex cycles of how material flows between galaxies and intergalactic space.

COS observed the quasar in far-ultraviolet light in August 2009. The instrument was installed by NASA astronauts in May 2009, during the servicing mission to upgrade and repair the 19-year-old Hubble telescope.

These Hubble observations of the quasar PKS 0405-123 are part of the Hubble Servicing Mission 4 Early Release Observations.

Spectrum of PKS 0405-123 quasar, showing evidence of intergalactic clouds at different distances

Hubble Space Telescope's newly repaired Advanced Camera for Surveys (ACS) has peered nearly 5 billion light-years away to resolve intricate details in the galaxy cluster Abell 370.

Abell 370 is one of the very first galaxy clusters where astronomers observed the phenomenon of gravitational lensing, where the warping of space by the cluster's gravitational field distorts the light from galaxies lying far behind it. This is manifested as arcs and streaks in the picture, which are the stretched images of background galaxies.

Gravitational lensing proves a vital tool for astronomers when measuring the dark matter distribution in massive clusters, since the mass distribution can be reconstructed from its gravitational effects.

Ground-based telescopic observations in the mid-1980s of the most prominent arc (near the right-hand side of the picture) allowed astronomers to deduce that the arc was not a structure of some kind within the cluster, but the gravitationally lensed image of an object two times farther away. Hubble resolves unseen new details in the arc that reveal structure in the lensed background galaxy.

Galaxy clusters are the most massive structures of the universe, located at the crossing of the filaments of the cosmic web of dark matter. The most massive clusters can contain up to 1,000 galaxies and intergalactic hot gas, all held together primarily by the gravity of dark matter.

These observations were taken with Hubble's Advanced Camera for Surveys (ACS) in its Wide Field mode on July 16, 2009. The composite image was made using filters that isolate light from green, red, and infrared wavelengths.

These Hubble data are part of the Hubble Servicing Mission 4 Early Release Observations.

Details of ACS Hubble image of galaxy cluster Abell 370

The signature balloon-shaped clouds of gas blown from a pair of massive stars called Eta Carinae have tantalized astronomers for decades. Eta Carinae has a volatile temperament, prone to violent outbursts over the past 200 years.

Observations by the newly repaired Space Telescope Imaging Spectrograph (STIS) aboard NASA's Hubble Space Telescope reveal a stream of charged particles from a massive stellar wind and some of the chemical elements that were ejected in the eruption seen in the middle of the nineteenth century.

STIS resolved the chemical information along a narrow section of one of the giant lobes of ejected material. In the resulting spectrum, iron and nickel define the outer material cast off in the nineteenth century from Eta Carinae. STIS also reveals the interior material being carried away by the ongoing wind from Eta Car A, the primary star. The amount of mass being carried away by the wind is the equivalent of one sun every thousand years.

While this "mass loss" may not sound very large, in fact it is an enormous rate among stars of all types. A very faint structure, seen in argon, is evidence of an interaction between winds from Eta Car A and those of Eta Car B, the hotter, less massive, secondary star.

Eta Car A is one of the most massive and most visible stars in the sky. Because of the star's extremely high mass, it is unstable and uses its fuel very quickly, compared to other stars. Such massive stars also have a short lifetime, and astronomers expect that Eta Carinae will explode within a million years.

Eta Carinae was first catalogued by Edmund Halley in 1677. In 1843 Eta Carinae was one of the brightest stars in the sky. It then slowly faded until, in 1868, it became invisible in the sky. Eta Carinae started to brighten again in the 1990s and was again visible to the naked eye. Around 1998 and 1999 its brightness suddenly and unexpectedly doubled.

Eta Carinae is 7,500 light-years away in the constellation Carina.

The Hubble observations are part of the Hubble Servicing Mission 4 Early Release Observations. NASA astronauts repaired STIS during a servicing mission in May to upgrade and repair the 19-year-old Hubble telescope.

WFPC2 image of the variable star Eta Carinae

STIS spectrum of the variable star Eta Carinae

This Hubble picture, taken on July 23, is the first full-disk natural-color image of Jupiter made with Hubble's new camera, the Wide Field Camera 3 (WFC3). It is the sharpest visible-light picture of Jupiter since the New Horizons spacecraft flew by that planet in 2007. Each pixel in this high-resolution image spans about 74 miles (119 km) in Jupiter's atmosphere. Jupiter was more than 370 million miles (600 million km) from Earth when the images were taken.

The dark smudge at bottom right is debris from a comet or asteroid that plunged into Jupiter's atmosphere and disintegrated.

In addition to the fresh impact, the image reveals a spectacular variety of shapes in the swirling atmosphere of Jupiter. The planet is wrapped in bands of yellow, brown, and white clouds. These bands are produced by the atmosphere flowing in different directions at various latitudes. When these opposing flows interact, turbulence appears.

Such data complement the images taken from other telescopes and spacecraft by providing exquisite details of atmospheric phenomena. For example, the image suggests that dark "barges" —- tracked by amateur astronomers on a nightly basis —- may differ both in form and color from barge features identified by the Voyager spacecraft. (The Great Red Spot and the smaller Red Oval are both out of view on the other side of the planet.)

This color image is a composite of three separate color exposures (red, blue, and green) made by WFC3. Additional processing was done to compensate for asynchronous imaging in the color filters and other effects.

Hubble WFC3 image of NGC 6302, planetary nebula in Scorpius

Jupiter in single filter F437W, imaged with the WFC3/UVIS detector.

This is the first image of a celestial object taken with the newly repaired Advanced Camera for Surveys (ACS). The camera was restored to operation during the STS-125 servicing mission to upgrade the Hubble Space Telescope.

The barred spiral galaxy NGC 6217 was photographed on June 13 and July 8, 2009, as part of the initial testing and calibration of Hubble's ACS. The galaxy lies 60 million light-years away in the north circumpolar constellation Ursa Minor.

Galaxy group Stephan's Quintet is located in the constellation Pegasus.

Globular Cluster Omega Centauri imaged with Hubble's WFC3 detector

Jet in the Carina Nebula taken with Hubble's WFC3 detector

This celestial object looks like a delicate butterfly. But it is far from serene.

What resemble dainty butterfly wings are actually roiling cauldrons of gas heated to more than 36,000 degrees Fahrenheit. The gas is tearing across space at more than 600,000 miles an hour—fast enough to travel from Earth to the Moon in 24 minutes!

A dying star that was once about five times the mass of the Sun is at the center of this fury. It has ejected its envelope of gases and is now unleashing a stream of ultraviolet radiation that is making the cast-off material glow. This object is an example of a planetary nebula, so-named because many of them have a round appearance resembling that of a planet when viewed through a small telescope.

The Wide Field Camera 3 (WFC3), a new camera aboard NASA's Hubble Space Telescope, snapped this image of the planetary nebula, catalogued as NGC 6302, but more popularly called the Bug Nebula or the Butterfly Nebula. WFC3 was installed by NASA astronauts in May 2009, during the servicing mission to upgrade and repair the 19-year-old Hubble telescope.

NGC 6302 lies within our Milky Way galaxy, roughly 3,800 light-years away in the constellation Scorpius. The glowing gas is the star's outer layers, expelled over about 2,200 years. The "butterfly" stretches for more than two light-years, which is about half the distance from the Sun to the nearest star, Alpha Centauri.

The central star itself cannot be seen, because it is hidden within a doughnut-shaped ring of dust, which appears as a dark band pinching the nebula in the center. The thick dust belt constricts the star's outflow, creating the classic "bipolar" or hourglass shape displayed by some planetary nebulae.

The star's surface temperature is estimated to be about 400,000 degrees Fahrenheit, making it one of the hottest known stars in our galaxy. Spectroscopic observations made with ground-based telescopes show that the gas is roughly 36,000 degrees Fahrenheit, which is unusually hot compared to a typical planetary nebula.

The WFC3 image reveals a complex history of ejections from the star. The star first evolved into a huge red-giant star, with a diameter of about 1,000 times that of our Sun. It then lost its extended outer layers. Some of this gas was cast off from its equator at a relatively slow speed, perhaps as low as 20,000 miles an hour, creating the doughnut-shaped ring. Other gas was ejected perpendicular to the ring at higher speeds, producing the elongated "wings" of the butterfly-shaped structure. Later, as the central star heated up, a much faster stellar wind, a stream of charged particles traveling at more than 2 million miles an hour, plowed through the existing wing-shaped structure, further modifying its shape.

The image also shows numerous finger-like projections pointing back to the star, which may mark denser blobs in the outflow that have resisted the pressure from the stellar wind.

The nebula's reddish outer edges are largely due to light emitted by nitrogen, which marks the coolest gas visible in the picture. WFC3 is equipped with a wide variety of filters that isolate light emitted by various chemical elements, allowing astronomers to infer properties of the nebular gas, such as its temperature, density, and composition.

The white-colored regions are areas where light is emitted by sulfur. These are regions where fast-moving gas overtakes and collides with slow-moving gas that left the star at an earlier time, producing shock waves in the gas (the bright white edges on the sides facing the central star). The white blob with the crisp edge at upper right is an example of one of those shock waves.

NGC 6302 was imaged on July 27, 2009, with Hubble's Wide Field Camera 3 in ultraviolet and visible light. Filters that isolate emissions from oxygen, helium, hydrogen, nitrogen, and sulfur from the planetary nebula were used to create this composite image.

These Hubble observations of the planetary nebula NGC 6302 are part of the Hubble Servicing Mission 4 Early Release Observations.

These two images of a huge pillar of star birth demonstrate how observations taken in visible and in infrared light by NASA's Hubble Space Telescope reveal dramatically different and complementary views of an object.

The pictures demonstrate one example of the broad wavelength range of the new Wide Field Camera 3 (WFC3) aboard the Hubble telescope, extending from ultraviolet to visible to infrared light.

Composed of gas and dust, the pillar resides in a tempestuous stellar nursery called the Carina Nebula, located 7,500 light-years away in the southern constellation Carina. The pair of images shows that astronomers have a much more complete view of the pillar and its contents when distinct details not seen at visible wavelengths are uncovered in near-infrared light.

The top image, taken in visible light, shows the tip of the 3-light-year-long pillar, bathed in the glow of light from hot, massive stars off the top of the image. Scorching radiation and fast winds (streams of charged particles) from these stars are sculpting the pillar and causing new stars to form within it. Streamers of gas and dust can be seen flowing off the top of the structure.

Nestled inside this dense structure are fledgling stars. They cannot be seen in this image because they are hidden by a wall of gas and dust. Although the stars themselves are invisible, one of them is providing evidence of its existence. Thin puffs of material can be seen traveling to the left and to the right of a dark notch in the center of the pillar. The matter is part of a jet produced by a young star. Farther away, on the left, the jet is visible as a grouping of small, wispy clouds. A few small clouds are visible at a similar distance on the right side of the jet. Astronomers estimate that the jet is moving at speeds of up to 850,000 miles an hour. The jet's total length is about 10 light-years.

In the image at bottom, taken in near-infrared light, the dense column and the surrounding greenish-colored gas all but disappear. Only a faint outline of the pillar remains. By penetrating the wall of gas and dust, the infrared vision of WFC3 reveals the infant star that is probably blasting the jet. Part of the jet nearest the star is more prominent in this view. These features can be seen because infrared light, unlike visible light, can pass through the dust.

Other infant stars inside the pillar also appear to emerge. Three examples are the bright star almost directly below the jet-producing star, a fainter one to its right, and a pair of stars at the top of the pillar. Winds and radiation from some of the stars are blowing away gas from their neighborhoods, carving out large cavities that appear as faint dark holes.

Surrounding the stellar nursery is a treasure chest full of stars, most of which cannot be seen in the visible-light image because dense gas clouds veil their light. Many of them are background stars.

Hubble's Wide Field Camera 3 observed the Carina Nebula on July 24-30, 2009. WFC3 was installed aboard Hubble in May 2009 during Servicing Mission 4. The composite image was made from filters that isolate emission from iron, magnesium, oxygen, hydrogen, and sulfur.

These Hubble observations of the Carina Nebula are part of the Hubble Servicing Mission 4 Early Release Observations.

Hubble WFC3 image of a stellar jet in Carina, observed in ultraviolet/visible light

Hubble WFC3 image of a stellar jet in Carina, observed in infrared light

Hubble WFC3 image of a stellar jet in Carina, observed in ultraviolet/visible/infrared light

Full-field image of a stellar jet in the Carina Nebula, imaged by Hubble's WFC3/UVIS detector

NASA's Hubble Space Telescope snapped this panoramic view of a colorful assortment of 100,000 stars residing in the crowded core of a giant star cluster.

The image reveals a small region inside the massive globular cluster Omega Centauri, which boasts nearly 10 million stars. Globular clusters, ancient swarms of stars united by gravity, are the homesteaders of our Milky Way galaxy. The stars in Omega Centauri are between 10 billion and 12 billion years old. The cluster lies about 16,000 light-years from Earth.

This is one of the first images taken by the new Wide Field Camera 3 (WFC3), installed aboard Hubble in May 2009, during Servicing Mission 4. The camera can snap sharp images over a broad range of wavelengths.

The photograph showcases the camera's color versatility by revealing a variety of stars in key stages of their life cycles.

The majority of the stars in the image are yellow-white, like our Sun. These are adult stars that are shining by hydrogen fusion. Toward the end of their normal lives, the stars become cooler and larger. These late-life stars are the orange dots in the image.

Even later in their life cycles, the stars continue to cool down and expand in size, becoming red giants. These bright red stars swell to many times larger than our Sun's size and begin to shed their gaseous envelopes.

After ejecting most of their mass and exhausting much of their hydrogen fuel, the stars appear brilliant blue. Only a thin layer of material covers their super-hot cores. These stars are desperately trying to extend their lives by fusing helium in their cores. At this stage, they emit much of their light at ultraviolet wavelengths.

When the helium runs out, the stars reach the end of their lives. Only their burned-out cores remain, and they are called white dwarfs (the faint blue dots in the image). White dwarfs are no longer generating energy through nuclear fusion and have gravitationally contracted to the size of Earth. They will continue to cool and grow dimmer for many billions of years until they become dark cinders.

Other stars that appear in the image are so-called "blue stragglers." They are older stars that acquire a new lease on life when they collide and merge with other stars. The encounters boost the stars' energy-production rate, making them appear bluer.

All of the stars in the image are cozy neighbors. The average distance between any two stars in the cluster's crowded core is only about a third of a light-year, roughly 13 times closer than our Sun's nearest stellar neighbor, Alpha Centauri. Although the stars are close together, WFC3's sharpness can resolve each of them as individual stars. If anyone lived in this globular cluster, they would behold a star-saturated sky that is roughly 100 times brighter than Earth's sky.

Globular clusters were thought to be assemblages of stars that share the same birth date. Evidence suggests, however, that Omega Centauri has at least two populations of stars with different ages. Some astronomers think that the cluster may be the remnant of a small galaxy that was gravitationally disrupted long ago by the Milky Way, losing stars and gas.

Omega Centauri is among the biggest and most massive of some 200 globular clusters orbiting the Milky Way. It is one of the few globular clusters that can be seen with the unaided eye. Named by Johann Bayer in 1603 as the 24th brightest object in the constellation Centaurus, it resembles a small cloud in the southern sky and might easily be mistaken for a comet.

Hubble observed Omega Centauri on July 15, 2009, in ultraviolet and visible light. These Hubble observations of Omega Centauri are part of the Hubble Servicing Mission 4 Early Release Observations.

This is a Hubble Advanced Camera for Surveys image of the globular star cluster Omega Centauri. This image was used in a zoom animation highlighting the Omega Centauri Hubble release image.

A clash among members of a famous galaxy quintet reveals an assortment of stars across a wide color range, from young, blue stars to aging, red stars.

This portrait of Stephan's Quintet, also known as Hickson Compact Group 92, was taken by the new Wide Field Camera 3 (WFC3) aboard NASA's Hubble Space Telescope. Stephan's Quintet, as the name implies, is a group of five galaxies. The name, however, is a bit of a misnomer. Studies have shown that group member NGC 7320, at upper left, is actually a foreground galaxy about seven times closer to Earth than the rest of the group.

Three of the galaxies have distorted shapes, elongated spiral arms, and long, gaseous tidal tails containing myriad star clusters, proof of their close encounters. These interactions have sparked a frenzy of star birth in the central pair of galaxies. This drama is being played out against a rich backdrop of faraway galaxies.

The image, taken in visible and near-infrared light, showcases WFC3's broad wavelength range.

The colors trace the ages of the stellar populations, showing that star birth occurred at different epochs, stretching over hundreds of millions of years. The camera's infrared vision also peers through curtains of dust to see groupings of stars that cannot be seen in visible light.

NGC 7319, at top right, is a barred spiral with distinct spiral arms that follow nearly 180 degrees back to the bar. The blue specks in the spiral arm at the top of NGC 7319 and the red dots just above and to the right of the core are clusters of many thousands of stars. Most of the quintet is too far away even for Hubble to resolve individual stars.

Continuing clockwise, the next galaxy appears to have two cores, but it is actually two galaxies, NGC 7318A and NGC 7318B. Encircling the galaxies are young, bright blue star clusters and pinkish clouds of glowing hydrogen where infant stars are being born. These stars are less than 10 million years old and have not yet blown away their natal cloud. Far away from the galaxies, at right, is a patch of intergalactic space where many star clusters are forming.

NGC 7317, at bottom left, is a normal-looking elliptical galaxy that is less affected by the interactions.

Sharply contrasting with these galaxies is the dwarf galaxy NGC 7320 at upper left. Bursts of star formation are occurring in the galaxy's disk, as seen by the blue and pink dots. In this galaxy, Hubble can resolve individual stars, evidence that NGC 7320 is closer to Earth.

NGC 7320 is 40 million light-years from Earth. The other members of the quintet reside 290 million light-years away in the constellation Pegasus.

These farther members are markedly redder than the foreground galaxy, suggesting that older stars reside in their cores. The stars' light also may be further reddened by dust stirred up in the encounters.

Spied by Edouard M. Stephan in 1877, Stephan's Quintet is the first compact group ever discovered.

WFC3 observed the quintet in July and August 2009. The composite image was made by using filters that isolate light from the blue, green, and infrared portions of the spectrum, as well as emission from ionized hydrogen.

These Hubble observations are part of the Hubble Servicing Mission 4 Early Release Observations. NASA astronauts installed the WFC3 camera during a servicing mission in May to upgrade and repair the 19-year-old Hubble telescope.

In celebration of the International Year of Astronomy 2009, NASA's Great Observatories — the Hubble Space Telescope, the Spitzer Space Telescope, and the Chandra X-ray Observatory — have collaborated to produce an unprecedented image of the central region of our Milky Way galaxy.

In this spectacular image, observations using infrared light and X-ray light see through the obscuring dust and reveal the intense activity near the galactic core. Note that the center of the galaxy is located within the bright white region to the right of and just below the middle of the image. The entire image width covers about one-half a degree, about the same angular width as the full moon.

Each telescope's contribution is presented in a different color:

- Yellow represents the near-infrared observations of Hubble. These observations outline the energetic regions where stars are being born as well as reveal hundreds of thousands of stars.

- Red represents the infrared observations of Spitzer. The radiation and winds from stars create glowing dust clouds that exhibit complex structures from compact, spherical globules to long, stringy filaments.

- Blue and violet represent the X-ray observations of Chandra. X-rays are emitted by gas heated to millions of degrees by stellar explosions and by outflows from the supermassive black hole in the galaxy's center. The bright blue blob on the left side is emission from a double star system containing either a neutron star or a black hole.

When these views are brought together, this composite image provides one of the most detailed views ever of our galaxy's mysterious core.

In celebration of the International Year of Astronomy 2009, NASA's Great Observatories — the Hubble Space Telescope, the Spitzer Space Telescope, and the Chandra X-ray Observatory — have produced a matched trio of images of the central region of our Milky Way galaxy. Each image shows the telescope's different wavelength view of the galactic center region, illustrating the unique science each observatory conducts.

[Top Frame] — Spitzer's infrared-light observations provide a detailed and spectacular view of the galactic center region. The swirling core of our galaxy harbors hundreds of thousands of stars that cannot be seen in visible light. These stars heat the nearby gas and dust. These dusty clouds glow in infrared light and reveal their often dramatic shapes. Some of these clouds harbor stellar nurseries that are forming new generations of stars. Like the downtown of a large city, the center of our galaxy is a crowded, active, and vibrant place.

[Middle Frame] — Although best known for its visible-light images, Hubble also observes over a limited range of infrared light. The galactic center is marked by the bright patch in the lower right. Along the left side are large arcs of warm gas that have been heated by clusters of bright massive stars. In addition, Hubble uncovered many more massive stars across the region. Winds and radiation from these stars create the complex structures seen in the gas throughout the image. This sweeping panorama is one of the sharpest infrared pictures ever made of the galactic center region.

[Bottom Frame] — X-rays detected by Chandra expose a wealth of exotic objects and high-energy features. In this image, pink represents lower energy X-rays and blue indicates higher energy. Hundreds of small dots show emission from material around black holes and other dense stellar objects. A supermassive black hole — some four million times more massive than the Sun — resides within the bright region in the lower right. The diffuse X-ray light comes from gas heated to millions of degrees by outflows from the supermassive black hole, winds from giant stars, and stellar explosions. This central region is the most energetic place in our galaxy.

Although best known for its visible-light images, the Hubble Space Telescope also observes over a limited range of infrared light. The galactic center is marked by the bright patch in the lower right. Along the left side are large arcs of warm gas that have been heated by clusters of bright massive stars. In addition, Hubble uncovered many more massive stars across the region. Winds and radiation from these stars create the complex structures seen in the gas throughout the image. This sweeping panorama is the sharpest infrared picture ever made of the galactic center region.

In celebration of the International Year of Astronomy 2009, NASA's Great Observatories — the Hubble Space Telescope, the Spitzer Space Telescope, and the Chandra X-ray Observatory — have collaborated to produce an unprecedented image of the central region of our Milky Way galaxy.

[Top Frame] — The spectacular composite image combines observations using infrared light and X-ray light that see through the obscuring dust and reveal the intense activity near the galactic core. Note that the center of the galaxy is located within the bright white region on the lower right-hand side of the image. Each telescope's contribution is presented in a different color. Yellow represents the near-infrared observations of Hubble. Red represents the infrared observations of Spitzer. Blue and violet represent the X-ray observations of Chandra.

[Bottom Left Frame] — Spitzer's infrared-light observations provide a detailed and spectacular view of the galactic center region. The swirling core of our galaxy harbors hundreds of thousands of stars that cannot be seen in visible light. These stars heat the nearby gas and dust. These dusty clouds glow in infrared light and reveal their often dramatic shapes. Some of these clouds harbor stellar nurseries that are forming new generations of stars. Like the downtown of a large city, the center of our galaxy is a crowded, active, and vibrant place.

[Bottom Middle Frame] — Although best known for its visible-light images, Hubble also observes over a limited range of infrared light. The galactic center is marked by the bright patch in the lower right. Along the left side are large arcs of warm gas that have been heated by clusters of bright massive stars. In addition, Hubble uncovered many more massive stars across the region. Winds and radiation from these stars create the complex structures seen in the gas throughout the image. This sweeping panorama is one of the sharpest infrared pictures ever made of the galactic center region.

[Bottom Right Frame] — X-rays detected by Chandra expose a wealth of exotic objects and high-energy features. In this image, pink represents lower energy X-rays and blue indicates higher energy. Hundreds of small dots show emission from material around black holes and other dense stellar objects. A supermassive black hole — some four million times more massive than the Sun — resides within the bright region in the lower right. The diffuse X-ray light comes from gas heated to millions of degrees by outflows from the supermassive black hole, winds from giant stars, and stellar explosions. This central region is the most energetic place in our galaxy.

The spectacular new camera installed on NASA's Hubble Space Telescope during Servicing Mission 4 in May has delivered the most detailed view of star birth in the graceful, curving arms of the nearby spiral galaxy M83.

Nicknamed the Southern Pinwheel, M83 is undergoing more rapid star formation than our own Milky Way galaxy, especially in its nucleus. The sharp "eye" of the Wide Field Camera 3 (WFC3) has captured hundreds of young star clusters, ancient swarms of globular star clusters, and hundreds of thousands of individual stars, mostly blue supergiants and red supergiants.

The image at right is Hubble's close-up view of the myriad stars near the galaxy's core, the bright whitish region at far right. An image of the entire galaxy, taken by the European Southern Observatory's Wide Field Imager on the ESO/MPG 2.2-meter telescope at La Silla, Chile, is shown at left. The white box outlines Hubble's view.

WFC3's broad wavelength range, from ultraviolet to near-infrared, reveals stars at different stages of evolution, allowing astronomers to dissect the galaxy's star-formation history.

The image reveals in unprecedented detail the current rapid rate of star birth in this famous "grand design" spiral galaxy. The newest generations of stars are forming largely in clusters on the edges of the dark dust lanes, the backbone of the spiral arms. These fledgling stars, only a few million years old, are bursting out of their dusty cocoons and producing bubbles of reddish glowing hydrogen gas.

The excavated regions give a colorful "Swiss cheese" appearance to the spiral arm. Gradually, the young stars' fierce winds (streams of charged particles) blow away the gas, revealing bright blue star clusters. These stars are about 1 million to 10 million years old. The older populations of stars are not as blue.

A bar of stars, gas, and dust slicing across the core of the galaxy may be instigating most of the star birth in the galaxy's core. The bar funnels material to the galaxy's center, where the most active star formation is taking place. The brightest star clusters reside along an arc near the core.

The remains of about 60 supernova blasts, the deaths of massive stars, can be seen in the image, five times more than known previously in this region. WFC3 identified the remnants of exploded stars. By studying these remnants, astronomers can better understand the nature of the progenitor stars, which are responsible for the creation and dispersal of most of the galaxy's heavy elements.

M83, located in the Southern Hemisphere, is often compared to M51, dubbed the Whirlpool galaxy, in the Northern Hemisphere. Located 15 million light-years away in the constellation Hydra, M83 is two times closer to Earth than M51.

Credit for Hubble image: NASA, ESA, R. O'Connell (University of Virginia), B. Whitmore (Space Telescope Science Institute), M. Dopita (Australian National University), and the Wide Field Camera 3 Science Oversight Committee

For additional information, contact:

Donna Weaver / Ray Villard
Space Telescope Science Institute, Baltimore, Md.
410-338-4493 / 410-338-4514
dweaver@stsci.edu / villard@stsci.edu

Robert O'Connell
University of Virginia, Charlottesville, Va.
434-924-7494
rwo@virginia.edu

Brad Whitmore
Space Telescope Science Institute, Baltimore, Md.
410-338-4474
whitmore@stsci.edu

The spectacular new camera installed on NASA's Hubble Space Telescope during Servicing Mission 4 in May has delivered the most detailed view of star birth in the graceful, curving arms of the nearby spiral galaxy M83.

Nicknamed the Southern Pinwheel, M83 is undergoing more rapid star formation than our own Milky Way galaxy, especially in its nucleus. The sharp "eye" of the Wide Field Camera 3 (WFC3) has captured hundreds of young star clusters, ancient swarms of globular star clusters, and hundreds of thousands of individual stars, mostly blue supergiants and red supergiants.

The image, taken in August 2009, provides a close-up view of the myriad stars near the galaxy's core, the bright whitish region at far right.

WFC3's broad wavelength range, from ultraviolet to near-infrared, reveals stars at different stages of evolution, allowing astronomers to dissect the galaxy's star-formation history.

The image reveals in unprecedented detail the current rapid rate of star birth in this famous "grand design" spiral galaxy. The newest generations of stars are forming largely in clusters on the edges of the dark dust lanes, the backbone of the spiral arms. These fledgling stars, only a few million years old, are bursting out of their dusty cocoons and producing bubbles of reddish glowing hydrogen gas.

The excavated regions give a colorful "Swiss cheese" appearance to the spiral arm. Gradually, the young stars' fierce winds (streams of charged particles) blow away the gas, revealing bright blue star clusters. These stars are about 1 million to 10 million years old. The older populations of stars are not as blue.

A bar of stars, gas, and dust slicing across the core of the galaxy may be instigating most of the star birth in the galaxy's core. The bar funnels material to the galaxy's center, where the most active star formation is taking place. The brightest star clusters reside along an arc near the core.

The remains of about 60 supernova blasts, the deaths of massive stars, can be seen in the image, five times more than known previously in this region. WFC3 identified the remnants of exploded stars. By studying these remnants, astronomers can better understand the nature of the progenitor stars, which are responsible for the creation and dispersal of most of the galaxy's heavy elements.

M83, located in the Southern Hemisphere, is often compared to M51, dubbed the Whirlpool galaxy, in the Northern Hemisphere. Located 15 million light-years away in the constellation Hydra, M83 is two times closer to Earth than M51.

The magnificent galaxy NGC 4710 is tilted nearly edge-on to our view from Earth. This perspective allows astronomers to easily distinguish the central bulge of stars from its pancake-flat disk of stars, dust, and gas. Like the yellow yolk on a fried egg, the central bulge extends outside of the central disk. Dark dust lanes — raw material for future generations of stars and planets — also appear confined to the central disk. What's striking in the image is a ghostly "X" pattern of stars. This is due to the inclined orbits of the stars in the galaxy's central bar-like structure. Located 65 million light-years away, NGC 4710 is a member of the giant Virgo Cluster of galaxies. It can be seen as a dim, 11th-magnitude, spindle-like smudge in a medium-sized amateur telescope. This natural-color photo was taken with the Hubble Space Telescope's Advanced Camera for Surveys on January 15, 2006.

For additional information, contact:

Colleen Sharkey
Hubble/ESA, Garching, Germany
011-49-89-3200-6306
csharkey@eso.org

NASA's Hubble Space Telescope has made the deepest image of the universe ever taken in near-infrared light. The faintest and reddest objects in the image are galaxies that formed 600 million years after the Big Bang. No galaxies have been seen before at such early times. The new deep view also provides insights into how galaxies grew in their formative years early in the universe's history.

The image was taken in the same region as the Hubble Ultra Deep Field (HUDF), which was taken in 2004 and is the deepest visible-light image of the universe. Hubble's newly installed Wide Field Camera 3 (WFC3) collects light from near-infrared wavelengths and therefore looks even deeper into the universe, because the light from very distant galaxies is stretched out of the ultraviolet and visible regions of the spectrum into near-infrared wavelengths by the expansion of the universe.

This image was taken by the HUDF09 team, which was awarded the time for the observation and made it available for research by astronomers worldwide. In just three months, 12 scientific papers have already been submitted on these new data.

The photo was taken with the new WFC3/IR camera on Hubble in late August 2009 during a total of four days of pointing for 173,000 seconds of total exposure time. Infrared light is invisible and therefore does not have colors that can be perceived by the human eye. The colors in the image are assigned comparatively short, medium, and long, near-infrared wavelengths (blue, 1.05 microns; green, 1.25 microns; red, 1.6 microns). The representation is "natural" in that blue objects look blue and red objects look red. The faintest objects are about one-billionth as bright as can be seen with the naked eye.

These Hubble observations are trailblazing a path for Hubble's successor, the James Webb Space Telescope (JWST), which will look even farther into the universe than Hubble, at infrared wavelengths. The JWST is planned to be launched in 2014.

The HUDF09 team members are Garth Illingworth (University of California Observatories/Lick Observatory and the University of California, Santa Cruz), Rychard Bouwens (University of California Observatories/Lick Observatory and Leiden University), Pascal Oesch and Marcella Carollo (Swiss Federal Institute of Technology, Zurich (ETH)), Marijn Franx (Leiden University), Ivo Labbe (Carnegie Institute of Washington), Daniel Magee (University of California, Santa Cruz), Massimo Stiavelli (Space Telescope Science Institute), Michele Trenti (University of Colorado, Boulder), and Pieter van Dokkum (Yale University).

For additional information, contact:

Ray Villard
Space Telescope Science Institute, Baltimore, Md.
410-338-4514
villard@stsci.edu

Garth Illingworth
University of California Observatories/Lick Observatory and
the University of California, Santa Cruz, Calif.
831-459-2843
gdi@ucolick.org

Just in time for the holidays: a Hubble Space Telescope picture postcard of hundreds of brilliant blue stars wreathed by warm, glowing clouds. The festive portrait is the most detailed view of the largest stellar nursery in our local galactic neighborhood.

The massive, young stellar grouping, called R136, is only a few million years old and resides in the 30 Doradus Nebula, a turbulent star-birth region in the Large Magellanic Cloud (LMC), a satellite galaxy of our Milky Way. There is no known star-forming region in our galaxy as large or as prolific as 30 Doradus.

Many of the diamond-like icy blue stars are among the most massive stars known. Several of them are over 100 times more massive than our Sun. These hefty stars are destined to pop off, like a string of firecrackers, as supernovas in a few million years.

The image, taken in ultraviolet, visible, and red light by Hubble's Wide Field Camera 3, spans about 100 light-years. The nebula is close enough to Earth that Hubble can resolve individual stars, giving astronomers important information about the stars' birth and evolution.

The brilliant stars are carving deep cavities in the surrounding material by unleashing a torrent of ultraviolet light, and hurricane-force stellar winds (streams of charged particles), which are etching away the enveloping hydrogen gas cloud in which the stars were born. The image reveals a fantasy landscape of pillars, ridges, and valleys, as well as a dark region in the center that roughly looks like the outline of a holiday tree. Besides sculpting the gaseous terrain, the brilliant stars can also help create a successive generation of offspring. When the winds hit dense walls of gas, they create shocks, which may be generating a new wave of star birth.

The movement of the LMC around the Milky Way may have triggered the massive cluster's formation in several ways. The gravitational tug of the Milky Way and the companion Small Magellanic Cloud may have compressed gas in the LMC. Also, the pressure resulting from the LMC plowing through the Milky Way's halo may have compressed gas in the satellite. The cluster is a rare, nearby example of the many super star clusters that formed in the distant, early universe, when star birth and galaxy interactions were more frequent. Previous Hubble observations have shown astronomers that super star clusters in faraway galaxies are ubiquitous.

The LMC is located 170,000 light-years away and is a member of the Local Group of Galaxies, which also includes the Milky Way.

The Hubble observations were taken Oct. 20-27, 2009. The blue color is light from the hottest, most massive stars; the green from the glow of oxygen; and the red from fluorescing hydrogen.

For additional information, contact:

Donna Weaver / Ray Villard
Space Telescope Science Institute, Baltimore, Md.
410-338-4493 / 410-338-4514
dweaver@stsci.edu / villard@stsci.edu

Francesco Paresce
National Institute for Astrophysics (INAF/IASF), Bologna, Italy
011-39-51-946576
fparesce@iasfbo.inaf.it

Robert O'Connell
University of Virginia, Charlottesville, Va.
434-924-7494
rwo@virginia.edu

These two images, taken in visible and infrared light by the Wide Field Camera 3 aboard NASA's Hubble Space Telescope, reveal a massive star cluster nestled in the largest stellar nursery in our local galactic neighborhood.

The massive, young stellar grouping, called R136, is only a few million years old and resides in the 30 Doradus Nebula, a turbulent star-birth region in the Large Magellanic Cloud (LMC), a satellite galaxy of our Milky Way. The nebula is close enough to Earth that Hubble can resolve individual stars, giving astronomers important information about the stars' birth and evolution.

In the image at left, taken in ultraviolet, visible, and red light, the stars look like icy blue diamonds. The green in the nebula is from the glow of oxygen and the red is from fluorescing hydrogen.

In the image at right, taken at infrared wavelengths, Hubble sees through the dusty nebula, revealing many stars that cannot be seen in the visible-light view. The large bright star just above the center of the image is in 30 Doradus. The observation was taken through two infrared filters (1.1 microns and 1.6 microns).

The Hubble observations of 30 Doradus were made Oct. 20-27, 2009.

The massive, young stellar grouping, called R136, is only a few million years old and resides in the 30 Doradus Nebula, a turbulent star-birth region in the Large Magellanic Cloud (LMC), a satellite galaxy of our Milky Way. Many of the stars are among the most massive known. Several of them are over 100 times more massive than our Sun. These hefty stars are destined to become supernovae in a few million years.

The image, taken by Hubble's Wide Field Camera 3, spans about 100 light-years. The nebula is close enough to Earth that Hubble can resolve individual stars, giving astronomers important information about the stars' birth and evolution.

The brilliant stars are carving deep cavities in the surrounding material by unleashing a torrent of ultraviolet light, and hurricane-force stellar winds (streams of charged particles), which are etching away the enveloping hydrogen gas cloud in which the stars were born. The image reveals a fantasy landscape of pillars, ridges, and valleys, as well as a dark region in the center that roughly looks like the outline of a holiday tree. Besides sculpting the gaseous terrain, the brilliant stars can also help create a successive generation of offspring. When the winds hit dense walls of gas, they create shocks, which may be generating a new wave of star birth.

The movement of the LMC around the Milky Way may have triggered the massive cluster's formation in several ways. The gravitational tug of the Milky Way and the companion Small Magellanic Cloud may have compressed gas in the LMC. Also, the pressure resulting from the LMC plowing through the Milky Way's halo may have compressed gas in the satellite. The cluster is a rare, nearby example of the many super star clusters that formed in the distant, early universe, when star birth and galaxy interactions were more frequent. Previous Hubble observations have shown astronomers that super star clusters in faraway galaxies are ubiquitous. The LMC is located 170,000 light-years away and is a member of the Local Group of Galaxies, which also includes the Milky Way.

The Hubble image was taken at infrared wavelengths (1.1 microns and 1.6 microns). Hubble sees through the dusty nebula, revealing many stars that cannot be seen in visible light. The large bright star just above the center of the image is in the 30 Doradus nebula. The Hubble observations of 30 Doradus were made October 20-27, 2009.

More than 12 billion years of cosmic history are shown in this unprecedented, panoramic, full-color view of thousands of galaxies in various stages of assembly.

This image, taken by NASA's Hubble Space Telescope, was made from mosaics taken in September and October 2009 with the newly installed Wide Field Camera 3 (WFC3) and in 2004 with the Advanced Camera for Surveys (ACS). The view covers a portion of the southern field of a large galaxy census called the Great Observatories Origins Deep Survey (GOODS), a deep-sky study by several observatories to trace the formation and evolution of galaxies.

The final image combines a broad range of colors, from the ultraviolet, through visible light, and into the near-infrared. Such a detailed multi-color view of the universe has never before been assembled in such a combination of color, clarity, accuracy, and depth.

Hubble's sharp resolution and new color versatility, produced by combining data from the two cameras, are allowing astronomers to sort out the various stages of galaxy formation. The image reveals galaxy shapes that appear increasingly chaotic at each earlier epoch, as galaxies grew through accretion, collisions, and mergers. The galaxies range from the mature spirals and ellipticals in the foreground, to smaller, fainter, irregularly shaped galaxies, most of which are farther away, and therefore existed farther back in time. These smaller galaxies are considered the building blocks of the larger galaxies we see today.

Astronomers are using this multi-color panorama to trace many details of galaxy assembly over cosmic time, including the star-formation rate in galaxies, the rate of mergers among galaxies, and the abundance of weak active galactic nuclei.

The image shows a rich tapestry of 7,500 galaxies stretching back through most of the universe's history. The closest galaxies seen in the foreground emitted their observed light about a billion years ago. The farthest galaxies, a few of the very faint red specks, are seen as they appeared more than 13 billion years ago, or roughly 650 million years after the Big Bang. This mosaic spans a slice of space that is equal to about a third of the diameter of the full Moon (10 arcminutes).

The new Hubble view highlights a wide variety of stages in the galaxy assembly process. Ultraviolet light taken by WFC3 shows the blue glow of hot, young stars in galaxies teeming with star birth. The orange light reveals the final buildup of massive galaxies about 8 billion to 10 billion years ago. The near-infrared light displays the red glow of very distant galaxies — in a few cases as far as 12 billion to 13 billion light-years away — whose light has been stretched, like a toy Slinky, from ultraviolet light to longer-wavelength infrared light due to the expansion of the universe.

In this ambitious use of Hubble's observing time, astronomers used 96 Hubble orbits to make the ACS optical observations of this slice of the GOODS field and 104 orbits to make the WFC3 ultraviolet and near-infrared exposures. WFC3 peered deeper into the universe in this study than comparable near-infrared observations from ground-based telescopes. This set of unique new Hubble observations reveals galaxies to about 27th magnitude in brightness over a factor of 10 in wavelength. That's over 250 million times fainter than the unaided eye can see in visual light from a dark ground-based site.

For additional information, contact:

Ray Villard
Space Telescope Science Institute, Baltimore, Md.
410-338-4514
villard@stsci.edu

Rogier Windhorst
Arizona State University, Tempe, Ariz.
480-965-7143 (office) or 480-540-0816 (cell)
rogier.windhorst@asu.edu

These three close-up views show the rich variety of galaxies that appear in the new panoramic, full-color image of the Great Observatories Origins Deep Survey (GOODS) field, taken by NASA's Hubble Space Telescope. The full field reveals 7,500 galaxies in various stages of assembly and stretching back through most of the universe's history.

Astronomers combined new observations taken by the Wide Field Camera 3 (WFC3) and data taken by the Advanced Camera for Surveys (ACS) to make this mosaic.

The image combines a broad range of colors, from the ultraviolet, through visible light, and into the near-infrared. Such a detailed multi-color view of the universe has never before been assembled in such a combination of color, clarity, accuracy, and depth.

Hubble's sharp resolution and new color versatility, produced by combining data from the two cameras, are allowing astronomers to sort out the various stages of galaxy formation. These three views reveal galaxy shapes that appear increasingly chaotic at each earlier epoch, as galaxies grew through accretion, collisions, and mergers. The galaxies range from the mature spirals and ellipticals in the foreground, to smaller, fainter, irregularly shaped galaxies, most of which are farther away, and therefore existed farther back in time. These smaller galaxies are considered the building blocks of the larger galaxies we see today.

Ultraviolet light taken by WFC3 shows the blue glow of hot, young stars in galaxies teeming with star birth. The orange light reveals the final buildup of massive galaxies about 8 billion to 10 billion years ago. The near-infrared light displays the red glow of very distant galaxies — in a few cases as far as 12 billion to 13 billion light-years away — whose light has been stretched, like a toy Slinky, from ultraviolet light to longer- wavelength infrared light due to the expansion of the universe.

The WFC3 observations were taken in September and October 2009; the ACS observations in 2004. The view covers a portion of the southern field of a large galaxy census called the Great Observatories Origins Deep Survey (GOODS), a deep-sky study by several observatories to trace the evolution of galaxies.

This is the deepest image of the universe ever taken in near-infrared light by NASA's Hubble Space Telescope. The faintest and reddest objects (left inset) in the image are galaxies that correspond to "look-back times" of approximately 12.9 billion years to 13.1 billion years ago. No galaxies have been seen before at such early epochs. These galaxies are much smaller than the Milky Way galaxy and have populations of stars that are intrinsically very blue. This may indicate the galaxies are so primordial that they are deficient in heavier elements, and as a result, are quite free of the dust that reddens light through scattering.

The image was taken with Hubble's newly installed Wide Field Camera 3 (WFC3), which collects light from near-infrared wavelengths and therefore looks even deeper into the universe. The light from very distant galaxies is stretched out of the ultraviolet and visible regions of the spectrum into near-infrared wavelengths by the expansion of the universe.

Hubble's WFC3 took this image in late August 2009 during a total of four days of pointing for 173,000 seconds of exposure time. Infrared light is invisible and therefore does not have colors that can be perceived by the human eye. The colors in the image are assigned comparatively short, medium, and long near-infrared wavelengths (blue, 1.05 microns; green, 1.25 microns; and red, 1.6 microns). The representation is "natural" in that blue objects appear blue and red objects look red. The faintest objects are about one-billionth as bright as can be seen with the naked eye. The galaxy distances are estimated from the infrared colors of their light.

These Hubble observations are trailblazing a path for Hubble's successor, the James Webb Space Telescope (JWST), which will look even farther into the universe than Hubble, at infrared wavelengths. The JWST is planned to be launched in 2014.

The image was created from Hubble data from proposal 11563: G. Illingworth (UCO/Lick Observatory and the University of California, Santa Cruz), R. Bouwens (UCO/Lick Observatory and Leiden University),M. Carollo (Swiss Federal Institute of Technology, Zurich), M. Franx (Leiden University), I. Labbe (Carnegie Institution of Washington), D.Magee (University of California, Santa Cruz), P. Oesch (Swiss Federal Institute of Technology, Zurich), M. Stiavelli (STScI), M. Trenti (University of Colorado, Boulder), and P. van Dokkum (Yale University).

This is a Hubble Space Telescope image of young brown dwarf 2M J044144. It has a companion object at the 8 o'clock position that is estimated to be 5-10 times the mass of Jupiter. In the right panel, the light from the brown dwarf has been subtracted to provide a clearer view of the companion object. The separation of the companion corresponds to 1.4 billion miles at the distance of the Taurus star-forming region, which is only about 1 million years old. The companion may be a very small brown dwarf or a large planet, depending on how it formed. Images were taken with Hubble's Wide Field Planetary Camera 2 to track the motion of the two objects to see if they actually do travel across space together. Additional observations were done with the Gemini North telescope on Mauna Kea, Hawaii.

NGC 2976 does not look like a typical spiral galaxy, as this NASA Hubble Space Telescope image shows.

In this view of the oddball galaxy's inner region, there are no obvious spiral arms. Dusty filaments running through the disk show no clear spiral structure. A raucous interaction with a neighboring group of hefty galaxies stripped away some gas and funneled the rest to the galaxy's inner region, fueling star birth about 500 million years ago. At the same time, the galaxy's outer regions stopped making stars because the gas ran out. Now, the inner disk is almost out of gas as new stars burst to life, shrinking the star-formation region to a small area of about 5,000 light-years around the core.

Astronomers pieced together the galaxy's star-formation story with the help of Hubble's sharp vision. The galaxy's relatively close distance to Earth allowed Hubble's Advanced Camera for Surveys (ACS) to resolve hundreds of thousands of individual stars. What look like grains of sand in the image are actually single stars.

Studying the individual stars allowed astronomers to determine their color and brightness, which provided information about when they formed. Based on this analysis, the astronomers reconstructed the star-making history for large areas of the galaxy.

The blue dots in the image are fledgling blue giant stars residing in the remaining active star-birth regions. NGC 2976 resides on the fringe of the M81 group of galaxies, located about 12 million light-years away in the constellation Ursa Major.

The observation is part of the ACS Nearby Galaxy Survey Treasury (ANGST) program. Data for the image were taken Dec. 27, 2006, to Jan. 10, 2007.

This is the most detailed view to date of the entire surface of the dwarf planet Pluto, as constructed from multiple NASA Hubble Space Telescope photographs taken from 2002 to 2003.

Hubble's view isn't sharp enough to see craters or mountains, if they exist on the surface, but Hubble reveals a complex-looking and variegated world with white, dark-orange, and charcoal-black terrain. The overall color is believed to be a result of ultraviolet radiation from the distant Sun breaking up methane that is present on Pluto's surface, leaving behind a dark, molasses-colored, carbon-rich residue.

The center disk (180 degrees) has a mysterious bright spot that is unusually rich in carbon monoxide frost. This region will be photographed in the highest possible detail when NASA's New Horizons probe flies by Pluto in 2015.

The Hubble images are a few pixels wide. But through a technique called dithering, multiple, slightly offset pictures can be combined through computer-image processing to synthesize a higher-resolution view than could be seen in a single exposure. This series of pictures took four years and 20 computers operating continuously and simultaneously to accomplish.

These are two Hubble photo maps of the dwarf planet Pluto, as seen in 1994 and 2002-2003. Hubble's view isn't sharp enough to see craters or mountains, if they exist on the surface, but Hubble does reveal a complex-looking and variegated world with white and charcoal-black terrain. The white areas are surface frost, and the dark areas are a carbon-rich residue caused by sunlight breaking up methane that is present on Pluto's surface.

A comparison of the maps shows that Pluto's brightness has changed between 1994 and 2003. The northern pole is brighter and the southern hemisphere is darker. Summer is approaching Pluto's north pole, and this may cause surface ices to melt and refreeze in the colder shadowed portion of the planet.

The Hubble pictures underscore that Pluto is not simply a ball of ice and rock but a dynamic world that undergoes dramatic atmospheric changes. These atmospheric changes are driven by seasonal changes that are as much propelled by the planet's 248-year elliptical orbit as its axial tilt, unlike Earth where the tilt alone drives seasons.

The top picture was taken in 1994 by the European Space Agency's Faint Object Camera. The bottom image was taken in 2002-2003 by the Advanced Camera for Surveys. The dark band at the bottom of each map is the region that was hidden from view at the time the data were taken.

This is the most detailed view to date of the entire surface of the dwarf planet Pluto, as constructed from multiple NASA Hubble Space Telescope photographs taken from 2002 to 2003. NASA's New Horizons space probe, now halfway to Pluto, will get sharper images of Pluto when it is six months away from a close flyby in 2015.

Hubble's view isn't sharp enough to see craters or mountains, if they exist on the surface, but Hubble reveals a complex-looking and variegated world with white, dark-orange, and charcoal-black terrain. The overall color is believed to be a result of ultraviolet radiation from the distant Sun breaking up methane that is present on Pluto's surface, leaving behind a dark, molasses-colored, carbon-rich residue.

Pluto is so small and distant that the task of resolving the surface is as challenging as trying to see the markings on a soccer ball 40 miles away. The Hubble raw images are a few pixels wide. But through a technique called dithering, multiple, slightly offset pictures can be combined through computer-image processing to synthesize a higher-resolution view than could be seen in a single exposure. This series of pictures took four years and 20 computers operating continuously and simultaneously to accomplish.

This is a NASA Hubble Space Telescope picture of a comet-like object called P/2010 A2, which was first discovered by the LINEAR (Lincoln Near-Earth Asteroid Research program) sky survey on January 6. The object appears so unusual in ground-based telescopic images that discretionary time on Hubble was used to take a close-up look. This picture, from the January 29 observation, shows a bizarre X-pattern of filamentary structures near the point-like nucleus of the object and trailing streamers of dust.

The inset picture shows a complex structure that suggests the object is not a comet but instead the product of a head-on collision between two asteroids traveling five times faster than a rifle bullet (5 kilometers per second). Astronomers have long thought that the asteroid belt is being ground down through collisions, but such a smashup has never before been seen.

The filaments are made of dust and gravel, presumably recently thrown out of the 460-foot-diameter nucleus. Some of the filaments are swept back by radiation pressure from sunlight to create straight dust streaks. Embedded in the filaments are co-moving blobs of dust that likely originate from tiny unseen parent bodies. An impact origin would also be consistent with the absence of gas in spectra recorded using ground-based telescopes.

At the time of the Hubble observations, the object was approximately 180 million miles (300 million km) from the Sun and 90 million miles (140 million km) from Earth. The Hubble images were recorded with the new Wide Field Camera 3 (WFC3). The image was taken in visible light. The color in the image is not what the human eye would see. A blue color map was added to bring out subtle details.

These four dwarf galaxies waited billions of years to come together, setting off a fireworks show as thousands of new star clusters come to life. The distorted galaxies are quickly producing massive, hot, young stars that are pumping out ultraviolet radiation, heating up surrounding gas clouds, and causing them to glow.

Such encounters between dwarf galaxies are normally seen billions of light-years away and therefore occurred billions of years ago. But these galaxies, members of Hickson Compact Group 31, are relatively nearby, only 166 million light-years away.

In this composite image of the galaxy grouping, the bright, distorted object at middle, left, is actually two colliding dwarf galaxies. Myriad star clusters have formed in the streamers of debris pulled from the galaxies and at the site of their head-on collision. The cigar-shaped object above the galaxy duo is another member of the group. A bridge of star clusters connects the trio. A long rope of bright star clusters points to the fourth member of the group, at lower right. The bright object in the center is a foreground star. The image was composed from observations made by the Hubble Space Telescope's Advanced Camera for Surveys, NASA's Spitzer Space Telescope, and the Galaxy Evolution Explorer (GALEX).

Astronomers used Hubble's Advanced Camera for Surveys to resolve the youngest and brightest of star clusters, which allowed them to calculate the clusters' ages, map the star-formation history, and determine that the galaxies are starting the final stages of galaxy assembly. Hubble reveals that the brightest clusters, hefty groups each holding at least 100,000 stars, are less than 10 million years old.

Astronomers say the interacting galaxies will form a large elliptical galaxy in another billion years.

The Advanced Camera for Surveys data were taken on Aug. 8, 2006. The principal investigator was Jane Charlton of Pennsylvania State University, University Park.

The Spitzer observations were made on Feb. 22, 2005. The principal investigator was Kelsey Johnson of the University of Virginia and the National Radio Astronomy Observatory, both in Charlottesville.

The GALEX data were taken on Dec. 27, 2004.

These four dwarf galaxies waited billions of years to come together, setting off a fireworks show as thousands of new star clusters come to life. The distorted galaxies are quickly producing massive, hot, young stars that are pumping out ultraviolet radiation, heating up surrounding gas clouds, and causing them to glow.

Such encounters between dwarf galaxies are normally seen billions of light-years away and therefore occurred billions of years ago. But these galaxies, members of Hickson Compact Group 31, are relatively nearby, only 166 million light-years away.

In this image, taken by NASA's Hubble Space Telescope, the bright, distorted object at middle, left, is actually two colliding dwarf galaxies. Myriad star clusters have formed in the streamers of debris pulled from the galaxies and at the site of their head-on collision. The cigar-shaped object above the galaxy duo is another member of the group. A bridge of star clusters connects the trio. A long rope of bright star clusters points to the fourth member of the group, at lower right. The bright object in the center is a foreground star.

Astronomers used Hubble's Advanced Camera for Surveys to resolve the youngest and brightest of star clusters, which allowed them to calculate the clusters' ages, map the star-formation history, and determine that the galaxies are starting the final stages of galaxy assembly. Hubble reveals that the brightest clusters, hefty groups each holding at least 100,000 stars, are less than 10 million years old.

Astronomers say the interacting galaxies will form a large elliptical galaxy in another billion years.

The Advanced Camera for Surveys data were taken on Aug. 8, 2006. The principal investigator was Jane Charlton of Pennsylvania State University, University Park.

In January and March 2009, astronomers using NASA's Hubble Space Telescope took advantage of a rare opportunity to record Saturn when its rings were edge-on, resulting in a unique movie featuring the nearly symmetrical light show at both of the giant planet's poles. It takes Saturn almost thirty years to orbit the Sun, with the opportunity to image both of its poles occurring only twice during that time.

The light shows, called aurorae, are produced when electrically charged particles race along the planet's magnetic field and into the upper atmosphere where they excite atmospheric gases, causing them to glow. Saturn's aurorae resemble the same phenomena that take place at the Earth's poles.

The 2009 Hubble Advanced Camera for Surveys observations have allowed astronomers to monitor the behavior of Saturn's poles in the same shot over a sustained period of time and to analyze the planet's northern and southern lights simultaneously. The northern auroral oval appears to be slightly smaller and more intense than the southern one, implying that Saturn's magnetic field is not equally distributed across the planet; it is slightly uneven and stronger in the north than the south.

For additional information, contact:

Colleen Sharkey
Hubble/ESA, Garching, Germany
011-49-89-3200-6306
csharkey@eso.org

Jonathan Nichols
University of Leicester, Leicester, United Kingdom
011-44-116-252-5049
jdn@ion.le.ac.uk

Cheryl Gundy
Space Telescope Science Institute, Baltimore, Md.
410-338-4707
gundy@stsci.edu

This craggy fantasy mountaintop enshrouded by wispy clouds looks like a bizarre landscape from Tolkien's "The Lord of the Rings" or a Dr. Seuss book, depending on your imagination. The NASA Hubble Space Telescope image, which is even more dramatic than fiction, captures the chaotic activity atop a three-light-year-tall pillar of gas and dust that is being eaten away by the brilliant light from nearby bright stars. The pillar is also being assaulted from within, as infant stars buried inside it fire off jets of gas that can be seen streaming from towering peaks.

This turbulent cosmic pinnacle lies within a tempestuous stellar nursery called the Carina Nebula, located 7,500 light-years away in the southern constellation Carina. The image celebrates the 20th anniversary of Hubble's launch and deployment into an orbit around Earth.

Scorching radiation and fast winds (streams of charged particles) from super-hot newborn stars in the nebula are shaping and compressing the pillar, causing new stars to form within it. Streamers of hot ionized gas can be seen flowing off the ridges of the structure, and wispy veils of gas and dust, illuminated by starlight, float around its towering peaks. The denser parts of the pillar are resisting being eroded by radiation much like a towering butte in Utah's Monument Valley withstands erosion by water and wind.

Nestled inside this dense mountain are fledgling stars. Long streamers of gas can be seen shooting in opposite directions off the pedestal at the top of the image. Another pair of jets is visible at another peak near the center of the image. These jets (known as HH 901 and HH 902, respectively) are the signpost for new star birth. The jets are launched by swirling disks around the young stars, which allow material to slowly accrete onto the stars' surfaces.

Hubble's Wide Field Camera 3 observed the pillar on Feb. 1-2, 2010. The colors in this composite image correspond to the glow of oxygen (blue), hydrogen and nitrogen (green), and sulfur (red).

These two images of a three-light-year-high pillar of star birth demonstrate how observations taken in visible and infrared light by NASA's Hubble Space Telescope reveal dramatically different and complementary views of an object. The pair of images demonstrate how Hubble's new panchromatic view of the universe shows striking differences between visible and infrared wavelengths. This turbulent cosmic pinnacle lies within a tempestuous stellar nursery called the Carina Nebula, located 7,500 light-years away in the southern constellation Carina. The images mark the 20th anniversary of Hubble's launch and deployment into an orbit around Earth.

[Left] — This visible-light view shows how scorching radiation and fast winds (streams of charged particles) from super-hot newborn stars in the nebula are shaping and compressing the pillar, causing new stars to form within it. Infant stars buried inside it fire off jets of gas that can be seen streaming from towering peaks. Streamers of hot ionized gas can be seen flowing off the ridges of the structure, and wispy veils of gas and dust, illuminated by starlight, float around it. The dense parts of the pillar are resisting being eroded by radiation much like a towering butte in Utah's Monument Valley withstands erosion by water and wind. The colors in this composite image correspond to the glow of oxygen (blue), hydrogen and nitrogen (green), and sulfur (red).

[Right] — This near-infrared-light image shows a plethora of stars behind the gaseous veil of the nebula's background wall of hydrogen, laced with dust. The foreground pillar becomes semi-transparent because infrared light from background stars penetrates through much of the dust. A few stars inside the pillar also become visible. The false colors are assigned to three different infrared wavelength ranges.

Hubble's Wide Field Camera 3 observed the pillar in February and March 2010.

This craggy fantasy mountaintop enshrouded by wispy clouds looks like a bizarre landscape from Tolkien's "The Lord of the Rings" or a Dr. Seuss book, depending on your imagination. The NASA Hubble Space Telescope photograph, which is stranger than fiction, captures the chaotic activity atop a three-light-year-tall pillar of gas and dust that is being eaten away by the brilliant light from nearby bright stars. The pillar is also being assaulted from within, as infant stars buried inside it fire off jets of gas that can be seen streaming from towering peaks.

This turbulent cosmic pinnacle lies within a tempestuous stellar nursery called the Carina Nebula, located 7,500 light-years away in the southern constellation Carina. The image marks the 20th anniversary of Hubble's launch and deployment into Earth orbit.

Scorching radiation and fast winds (streams of charged particles) from hot newborn stars in the nebula are shaping and compressing the pillar, causing new stars to form within it. Streamers of hot ionized gas can be seen flowing off the ridges of the structure, and wispy veils of dust, illuminated by starlight, float around its peaks. The pillar is resisting being eroded by radiation much like a towering butte in Utah's Monument Valley withstands erosion by water and wind.

Nestled inside this dense mountain are fledgling stars. Long streamers of gas can be seen shooting in opposite directions off the pedestal at the top of the image. Another pair of jets is visible at another peak near the center of the image. These jets are the signpost for new star birth. The jets are launched by swirling disks around the stars, as these disks allow material to slowly accrete onto the stars' surfaces.

Hubble's Wide Field Camera 3 observed the pillar on Feb. 1-2, 2010. The colors in this composite image correspond to the glow of oxygen (blue), hydrogen and nitrogen (green), and sulfur (red).

This is a series of close-up views of the complex gas structures in a small portion of the Carina Nebula. The nebula is a cold cloud of predominantly hydrogen gas. It is laced with dust, which makes the cloud opaque. The cloud is being eroded by a gusher of ultraviolet light from young stars in the region. They sculpt a variety of fantasy shapes, many forming tadpole-like structures. In some frames, smaller pieces of nebulosity can be seen freely drifting, such as the 2.3-trillion-mile-long structure at upper right. The most striking feature is a 3.5-trillion-mile-long horizontal jet in the upper left frame. It is being blasted into space by a young star hidden in the tip of the pillar-like structure. A bowshock has formed near the tip of the jet.

NASA's Hubble Space Telescope captured this billowing cloud of cold interstellar gas and dust rising from a tempestuous stellar nursery located in the Carina Nebula, 7,500 light-years away in the southern constellation Carina. This pillar of dust and gas serves as an incubator for new stars and is teeming with new star-forming activity.

Hot, young stars erode and sculpt the clouds into this fantasy landscape by sending out thick stellar winds and scorching ultraviolet radiation. The low-density regions of the nebula are shredded while the denser parts resist erosion and remain as thick pillars. In the dark, cold interiors of these columns new stars continue to form.

In the process of star formation, a disk around the proto-star slowly accretes onto the star's surface. Part of the material is ejected along jets perpendicular to the accretion disk. The jets have speeds of several hundreds of miles per second. As these jets plow into the surround nebula, they create small, glowing patches of nebulosity, called Herbig-Haro (HH) objects.

Long streamers of gas can be seen shooting in opposite directions off the pedestal on the upper right-hand side of the image. Another pair of jets is visible in a peak near the top-center of the image. These jets (known as HH 901 and HH 902, respectively) are common signatures of the births of new stars.

This image celebrates the 20th anniversary of Hubble's launch and deployment into an orbit around Earth. Hubble's Wide Field Camera 3 observed the pillar on Feb. 1-2, 2010. The colors in this composite image correspond to the glow of oxygen (blue), hydrogen and nitrogen (green), and sulfur (red).

This is a NASA Hubble Space Telescope near-infrared-light image of a three-light-year-tall pillar of gas and dust that is being eaten away by the brilliant light from nearby stars in the tempestuous stellar nursery called the Carina Nebula, located 7,500 light-years away in the southern constellation Carina. The image marks the 20th anniversary of Hubble's launch and deployment into an orbit around Earth.

The image reveals a plethora of stars behind the gaseous veil of the nebula's wall of hydrogen, laced with dust. The foreground pillar becomes semi-transparent because infrared light from background stars penetrates through much of the dust. A few stars inside the pillar also become visible. The false colors are assigned to three different infrared wavelength ranges.

Hubble's Wide Field Camera 3 observed the pillar in February and March 2010.

This image of the 30 Doradus nebula, a rambunctious stellar nursery, and the enlarged inset photo show a heavyweight star that may have been kicked out of its home by a pair of heftier siblings.

In the inset image at right, an arrow points to the stellar runaway and a dashed arrow to its presumed direction of motion. The image was taken by the Wide Field and Planetary Camera 2 (WFPC2) aboard NASA's Hubble Space Telescope. The heavyweight star, called 30 Dor #016, is 90 times more massive than the Sun and is traveling at more than 250,000 miles an hour.

In the wider view of 30 Doradus, the homeless star, located on the outskirts of the nebula, is centered within a white box. The box shows Hubble's field of view. The image was taken by the European Southern Observatory's (ESO) Wide Field Imager at the 2.2-meter telescope on La Silla, Chile.

The young star, only 1 million to 2 million years old, may have traveled about 375 light-years from its suspected home in R136, the bright star cluster marked by a circle. Nestled in the core of 30 Doradus, R136 is one of the most massive young star clusters in nearby galaxies, containing several stars topping 100 solar masses each. 30 Doradus, also called the Tarantula Nebula, resides roughly 170,000 light-years from Earth, in the Large Magellanic Cloud.

Instruments at three observatories, including Hubble's WFPC2 and recently installed Cosmic Origins Spectrograph, have provided tantalizing clues that the star was ejected from R136.

In the ESO and WFPC2 images, hot stars are represented by the color blue. Hydrogen is in red and oxygen in green. Radiation from the runaway star is making the nebula glow.

The Hubble image was taken on June 30, 1995; the ESO image was released in December 2006.

The runaway star research team consists of C. Evans, V. Henault-Brunet, and W. Taylor (Royal Observatory Edinburgh); N. Walborn and D. Massa (Space Telescope Science Institute, Baltimore); D. Lennon (European Space Agency/Space Telescope Science Institute); P. Crowther (University of Sheffield, UK); I. Howarth (University College London); H. Sana (ESO/University of Amsterdam); and J. van Loon (Keele University, UK).

These NASA Hubble Space Telescope snapshots reveal an impact scar on Jupiter fading from view over several months between July 2009 and November 2009.

The Hubble image of Jupiter's full disk was taken July 23, 2009, revealing an elongated, dark spot at lower, right (inside the rectangular box).

The photograph was taken four days after an amateur astronomer first spotted the scar. The unexpected blemish was created when an unknown object plunged into Jupiter and exploded, scattering debris into the giant planet's cloud tops. The strike was equal to the explosion of a few thousand standard nuclear bombs.

The series of close-up images at right, taken between July 23, 2009 and Nov. 3, 2009, show the impact site rapidly disappearing. Jupiter's winds also are spreading the debris into intricate swirls.

To determine the nature of the culprit that smacked Jupiter, astronomers compared the Hubble images of the 2009 impact site with Hubble photographs of the Comet P/Shoemaker-Levy 9 (SL9) assault on Jupiter in July 1994. In the SL9 collision, more than 20 pieces of a known comet bombarded Jupiter.

Based on that comparison, astronomers say the intruder may have been a rogue asteroid about 1,600 feet (500 meters) wide. The images of the 2009 impact, therefore, may show for the first time the immediate aftermath of an asteroid striking another planet.

One clue pointing to a possible asteroid strike is the swiftly vanishing impact site, which may be due to a lack of lightweight particles in the debris. An asteroid collision may produce fewer fine particles than a strike by a dusty comet.

The impact site's elongated shape also indicates that the object descended from a shallower angle than the SL9 fragments.

The natural-color images are composites made from separate exposures in blue, green, and red light.

Astronomers find that the supermassive black hole at the center of the most massive local galaxy (M87) is not where it was expected. Their research, conducted using the Hubble Space Telescope, concludes that the supermassive black hole in M87 is displaced from the galaxy center.

At right is a large-scale image of galaxy M87 taken in 1998 with Hubble's Wide-Field Planetary Camera 2. The two images at left show an image taken in 2006 with Hubble's Advanced Camera for Surveys. The position of the supermassive black hole is indicated by the black dot in the lower left panel, and a knot in the jet (HST-1), which was flaring in 2006, is also indicated on this panel. The red dot indicates the center of the galaxy's light distribution, which is offset from the position of the black hole by about 22 light-years.

For more information, contact:

Karen Rhine
Florida Institute of Technology Office of Communications
321-674-8964
krhine@fit.edu

Daniel Batcheldor
Florida Institute of Technology, Melbourne, Fla.
321-674-7717
dbatcheldor@fit.edu

Eric Perlman
Florida Institute of Technology, Melbourne, Fla.
321-674-7741
eperlman@fit.edu

This NASA Hubble Space Telescope image shows the hypervelocity star that was kicked out of the center of our Milky Way galaxy with enough energy to escape the galaxy's gravitational grip. Dubbed HE 0437-5439, the stellar speedster may have been a member of a triple-star system and was jettisoned from the galaxy by the monster central black hole.

Galaxies in this image provide a grid of landmarks, which astronomers used to measure the full speed of this stellar outcast over 3 1/2 years. The stellar outcast is rocketing through the Milky Way's distant outskirts at 1.6 million miles an hour, high above the galaxy's disk, about 200,000 light-years from the center. The star is destined to roam the empty depths of intergalactic space.

Based on the speed and position of HE 0437-5439, the star would need 100 million years to have journeyed from the Milky Way's core. Yet its mass — nine times that of our Sun — and blue color mean that it should have burned out after only 20 million years — far shorter than the transit time it took to get to its current location. The most likely explanation for this paradox is that the star is a blue straggler, a pair of smaller and longer-lived stars that merged during flight.

Hubble's Advanced Camera for Surveys made this observation on July 8, 2006, in near-infrared light.

Detailed observations made by the Hubble Space Telescope have found an answer to the flash of light seen June 3 on Jupiter. It came from a giant meteor burning up high above Jupiter's cloud tops. The space visitor did not plunge deep enough into the atmosphere to explode and leave behind any telltale cloud of debris, as seen in previous Jupiter collisions.

Hubble's sharp vision and ultraviolet sensitivity were brought to bear on seeking out any trace evidence of the aftermath of the cosmic collision (right inset). Images taken on June 7 show no sign of dark debris above Jupiter's cloud tops. This means that the object didn't descend beneath the clouds and explode as a fireball. If it had, dark sooty blast debris would have been ejected and subsequently would have settled down onto the cloud tops.

Australian amateur astronomer Anthony Wesley saw the flash at 4:31 p.m. (EDT) on June 3. He was watching a live video feed of Jupiter from his telescope. In the Philippines, amateur astronomer Chris Go confirmed that he had simultaneously recorded the transitory event on video.

This natural color photo was taken in visible light with Hubble's Wide Field Camera 3.

The giant stormy planet Jupiter has gone through a makeover, as seen in these comparative Hubble Space Telescope images taken nearly 11 months apart. Several months ago the dark Southern Equatorial Belt (SEB) vanished. The last time this happened was in the early 1970s, when we didn't have powerful enough telescopes to study the change in detail.

Left
A Hubble picture from July 23, 2009, captures the planet's common appearance over the past several decades with alternating zones of high altitude ammonia ice crystal clouds (white strips) and belts of lower altitude material (dark strip). The image was taken to study a wispy patch of dark debris in the far Southern Hemisphere caused by the suspected explosion of an asteroid plunging into the lower atmosphere on July 19, 2009.

Right
A Hubble picture from June 7, 2010, reveals a slightly higher altitude layer of white ammonia ice crystal clouds that appears to obscure the deeper, darker belt clouds of the SEB. The team predicts that these clouds should clear out in a few months.

Hubble also resolved a string of dark spots farther south of the vanished belt. Based on past observations, the Hubble Jupiter team expects to see similar spots appear in the SEB, right before its white clouds clear out in a few months.

These natural color comparative planet portraits were taken in visible light with Hubble's new Wide Field Camera 3.

Like a July 4 fireworks display, a young, glittering collection of stars looks like an aerial burst. The cluster is surrounded by clouds of interstellar gas and dust—the raw material for new star formation. The nebula, located 20,000 light-years away in the constellation Carina, contains a central cluster of huge, hot stars, called NGC 3603.

This environment is not as peaceful as it looks. Ultraviolet radiation and violent stellar winds have blown out an enormous cavity in the gas and dust enveloping the cluster, providing an unobstructed view of the cluster.

Most of the stars in the cluster were born around the same time but differ in size, mass, temperature, and color. The course of a star's life is determined by its mass, so a cluster of a given age will contain stars in various stages of their lives, giving an opportunity for detailed analyses of stellar life cycles. NGC 3603 also contains some of the most massive stars known. These huge stars live fast and die young, burning through their hydrogen fuel quickly and ultimately ending their lives in supernova explosions.

Star clusters like NGC 3603 provide important clues to understanding the origin of massive star formation in the early, distant universe. Astronomers also use massive clusters to study distant starbursts that occur when galaxies collide, igniting a flurry of star formation. The proximity of NGC 3603 makes it an excellent lab for studying such distant and momentous events.

This Hubble Space Telescope image was captured in August 2009 and December 2009 with the Wide Field Camera 3 in both visible and infrared light, which trace the glow of sulfur, hydrogen, and iron.

A long-exposure Hubble Space Telescope image shows a majestic face-on spiral galaxy located deep within the Coma Cluster of galaxies, which lies 320 million light-years away in the northern constellation Coma Berenices.

The galaxy, known as NGC 4911, contains rich lanes of dust and gas near its center. These are silhouetted against glowing newborn star clusters and iridescent pink clouds of hydrogen, the existence of which indicates ongoing star formation. Hubble has also captured the outer spiral arms of NGC 4911, along with thousands of other galaxies of varying sizes. The high resolution of Hubble's cameras, paired with considerably long exposures, made it possible to observe these faint details.

NGC 4911 and other spirals near the center of the cluster are being transformed by the gravitational tug of their neighbors. In the case of NGC 4911, wispy arcs of the galaxy's outer spiral arms are being pulled and distorted by forces from a companion galaxy (NGC 4911A), to the upper right. The resultant stripped material will eventually be dispersed throughout the core of the Coma Cluster, where it will fuel the intergalactic populations of stars and star clusters.

The Coma Cluster is home to almost 1,000 galaxies, making it one of the densest collections of galaxies in the nearby universe. It continues to transform galaxies at the present epoch, due to the interactions of close-proximity galaxy systems within the dense cluster. Vigorous star formation is triggered in such collisions.

Galaxies in this cluster are so densely packed that they undergo frequent interactions and collisions. When galaxies of nearly equal masses merge, they form elliptical galaxies. Merging is more likely to occur in the center of the cluster where the density of galaxies is higher, giving rise to more elliptical galaxies.

This natural-color Hubble image, which combines data obtained in 2006, 2007, and 2009 from the Wide Field Planetary Camera 2 and the Advanced Camera for Surveys, required 28 hours of exposure time.

For additional information, contact:

Ray Villard
Space Telescope Science Institute, Baltimore, Md.
410-338-4514
villard@stsci.edu

Mario Livio
Space Telescope Science Institute, Baltimore, Md.
410-338-4439
mlivio@stsci.edu

Michael Gregg
University of California, Davis, Institute for Geophysics and Planetary Physics, Livermore, Calif.
925-423-8946
gregg@igpp.ucllnl.org

A beautiful new image of two colliding galaxies has been released by NASA's Great Observatories. The Antennae galaxies, located about 62 million light-years from Earth, are shown in this composite image from the Chandra X-ray Observatory (blue), the Hubble Space Telescope (gold and brown), and the Spitzer Space Telescope (red). The Antennae galaxies take their name from the long antenna-like "arms," seen in wide-angle views of the system. These features were produced by tidal forces generated in the collision.

The collision, which began more than 100 million years ago and is still occurring, has triggered the formation of millions of stars in clouds of dust and gas in the galaxies. The most massive of these young stars have already sped through their evolution in a few million years and exploded as supernovas.

The X-ray image from Chandra shows huge clouds of hot, interstellar gas that have been injected with rich deposits of elements from supernova explosions. This enriched gas, which includes elements such as oxygen, iron, magnesium, and silicon, will be incorporated into new generations of stars and planets. The bright, point-like sources in the image are produced by material falling onto black holes and neutron stars that are remnants of the massive stars. Some of these black holes may have masses that are almost one hundred times that of the Sun.

The Spitzer data show infrared light from warm dust clouds that have been heated by newborn stars, with the brightest clouds lying in the overlapping region between the two galaxies.

The Hubble data reveal old stars and star-forming regions in gold and white, while filaments of dust appear in brown. Many of the fainter objects in the optical image are clusters containing thousands of stars.

The Chandra image was taken in December 1999. The Spitzer image was taken in December 2003. The Hubble image was taken in July 2004 and February 2005.

For additional information, contact:

Megan Watzke
Chandra X-ray Center, Cambridge, Mass.
617-496-7998
mwatzke@cfa.harvard.edu

Whitney Clavin
Jet Propulsion Laboratory, Pasadena, Calif.
818-354-4673
whitney.clavin@jpl.nasa.gov

Cheryl Gundy
Space Telescope Science Institute, Baltimore, Md.
410-338-4707
gundy@stsci.edu

This is the Hubble Space Telescope image of the inner region of Abell 1689, an immense cluster of galaxies located 2.2 billion light-years away. Dark matter in the cluster is mapped by plotting the plethora of arcs produced by the light from background galaxies that is warped by the foreground cluster's gravitational field. Dark matter cannot be photographed, but its distribution is shown in the blue overlay. The dark matter concentration and distribution is then used to better understand the nature of dark energy, a pressure that is accelerating the expansion of the universe. The imaging data used in the natural-color photo was taken in 2002 with Hubble's Advanced Camera for Surveys.

A delicate sphere of gas, photographed by NASA's Hubble Space Telescope, floats serenely in the depths of space. The pristine shell, or bubble, is the result of gas that is being shocked by the expanding blast wave from a supernova. Called SNR 0509-67.5 (or SNR 0509 for short), the bubble is the visible remnant of a powerful stellar explosion in the Large Magellanic Cloud (LMC), a small galaxy about 160,000 light-years from Earth.

Ripples in the shell's surface may be caused by either subtle variations in the density of the ambient interstellar gas, or possibly driven from the interior by pieces of the ejecta. The bubble-shaped shroud of gas is 23 light-years across and is expanding at more than 11 million miles per hour (5,000 kilometers per second).

Astronomers have concluded that the explosion was one of an especially energetic and bright variety of supernovae. Known as Type Ia, such supernova events are thought to result from a white dwarf star in a binary system that robs its partner of material, takes on much more mass than it is able to handle, and eventually explodes.

Hubble's Advanced Camera for Surveys observed the supernova remnant on Oct. 28, 2006, with a filter that isolates light from glowing hydrogen seen in the expanding shell. These observations were then combined with visible-light images of the surrounding star field that were imaged with Hubble's Wide Field Camera 3 on Nov. 4, 2010.

With an age of about 400 years as seen from Earth, the supernova might have been visible to southern hemisphere observers around the year 1600. However, there are no known records of a "new star" in the direction of the LMC near that time. A more recent supernova in the LMC, SN 1987A, did catch the eye of Earth viewers and continues to be studied with ground- and space-based telescopes, including Hubble.

For additional information, contact:

Ray Villard
Space Telescope Science Institute, Baltimore, Md.
410-338-4514
villard@stsci.edu

Keith Noll
Space Telescope Science Institute, Baltimore, Md.
410-338-1828
noll@stsci.edu

This colorful creation was made by combining data from two of NASA's Great Observatories. Optical data of SNR 0509-67.5 and its accompanying star field, taken with the Hubble Space Telescope, are composited with X-ray images from the Chandra X-ray Observatory. The result shows soft green and blue hues of heated material from the X-ray data surrounded by the glowing pink optical shell, which shows the ambient gas being shocked by the expanding blast wave from the supernova. Ripples in the shell's appearance coincide with brighter areas of the X-ray data.

The Type Ia supernova that resulted in the creation of SNR 0509-67.5 occurred nearly 400 years ago for Earth viewers. The supernova remnant and its progenitor star reside in the Large Magellanic Cloud (LMC), a small galaxy about 160,000 light-years from Earth. The bubble-shaped shroud of gas is 23 light-years across and is expanding at more than 11 million miles per hour (5,000 kilometers per second).

Data from Hubble's Advanced Camera for Surveys, taken in 2006 with a filter that isolates light from glowing hydrogen, were combined with visible-light images of the surrounding star field that were taken with Hubble's Wide Field Camera 3 in 2010. These data were then merged with X-ray data from the Chandra X-ray Observatory taken with the Advanced CCD Imaging Spectrometer (ACIS) in 2000 and 2007.

The multicolor snapshot, at top, taken with Wide Field Camera 3 aboard NASA's Hubble Space Telescope, captures the central region of the giant globular cluster Omega Centauri. All the stars in the image are moving in random directions, like a swarm of bees. Astronomers used Hubble's exquisite resolving power to measure positions for stars in 2002 and 2006.

From these measurements, they can predict the stars' future movement. The bottom illustration charts the future positions of the stars highlighted by the white box in the top image. Each streak represents the motion of the star over the next 600 years. The motion between dots corresponds to 30 years.

Enjoying a frozen treat on a hot summer day can leave a sticky mess as it melts in the Sun and deforms. In the cold vacuum of space, there is no edible ice cream, but there is radiation from massive stars that is carving away at cold molecular clouds, creating bizarre, fantasy-like structures.

These one-light-year-tall pillars of cold hydrogen and dust, imaged by the Hubble Space Telescope, are located in the Carina Nebula. Violent stellar winds and powerful radiation from massive stars are sculpting the surrounding nebula. Inside the dense structures, new stars may be born.

This image of dust pillars in the Carina Nebula is a composite of 2005 observations taken of the region in hydrogen light (light emitted by hydrogen atoms) along with 2010 observations taken in oxygen light (light emitted by oxygen atoms), both times with Hubble's Advanced Camera for Surveys. The immense Carina Nebula is an estimated 7,500 light-years away in the southern constellation Carina.

For additional information, contact:

Ray Villard
Space Telescope Science Institute, Baltimore, Md.
410-338-4514
villard@stsci.edu

Mario Livio
Space Telescope Science Institute, Baltimore, Md.
410-338-4439
mlivio@stsci.edu

Keith Noll
Space Telescope Science Institute, Baltimore, Md.
410-338-1828
noll@stsci.edu

[LEFT] This is the Carina Nebula as imaged by ground-based telescopes at the Cerro Tololo Inter-american Observatory (CTIO) in La Serena, Chile. Narrow-band filters which allow emission from oxygen, hydrogen, and oxygen were used to create this multi-colored image. The white box outlines the Hubble Space Telescope/CTIO Carina Nebula mosaic, released in 2007. Image courtesy of N. Smith (University of California, Berkeley) and NOAO/AURA/NSF.

[TOP RIGHT] This is the Hubble Space Telescope/CTIO mosaic of a subsection of the Carina Nebula. CTIO emission filters were combined with Hubble Advanced Camera for Surveys (ACS) data taken with filters that isolate hydrogen emission. This higher-resolution ACS image was used as a luminosity layer and combined with the multi-filtered CTIO data. The white box outline indicates the Carina Nebula dust pillars. Image courtesy of NASA, ESA, N. Smith (University of California, Berkeley), and the Hubble Heritage Team (STScI/AURA).

[BOTTOM RIGHT] This is a photo of the Carina Nebula dust pillars imaged with Hubble's Advanced Camera for Surveys (ACS) detector using filters that allow emission from hydrogen (from 2005 data) and oxygen (2010 data). The recent oxygen observations were a "bonus" dataset that resulted when the ACS was used "in parallel" with the Wide Field Camera (WFC) as that detector imaged Herbig-Haro objects 901/902 in February 2010 for Hubble's 20th Anniversary image release. Image courtesy of NASA, ESA, the Hubble Heritage Team (STScI/AURA), N. Smith (University of California, Berkeley), and M. Livio (STScI).

This image shows the entire region around supernova 1987A. The most prominent feature in the image is a ring with dozens of bright spots. A shock wave of material unleashed by the stellar blast is slamming into regions along the ring's inner regions, heating them up, and causing them to glow. The ring, about a light-year across, was probably shed by the star about 20,000 years before it exploded.

This ultraviolet-light data from the Hubble Space Telescope's Cosmic Origins Spectrograph shows strong helium II absorption and transmission lines from a quasar, identifying an era 11.7 to 11.3 billion years ago when electrons were stripped from primeval helium atoms — a process called reionization.

This is an artist's concept of a craggy piece of solar system debris that belongs to a class of bodies called trans-Neptunian objects (TNOs). Most TNOs are small and faint, making them difficult to spot. Generally, they are more than 100 million times fainter than objects visible to the unaided eye. The newfound TNOs range from 25 to 60 miles (40-100 km) across. In this illustration, the distant Sun is reduced to a bright star at a distance of over 3 billion miles. Astronomers culling the data archives of NASA's Hubble Space Telescope have added 14 new TNOs to the catalog. Their search method promises to turn up hundreds more.

NASA's Hubble Space Telescope snapped these images of the asteroid Vesta in preparation for the Dawn spacecraft's visit in 2011.

Each of the four Hubble images captures views of Vesta during its 5.34-hour rotation period. Hubble's sharp "eye" can see features as small as about 25 miles (40 kilometers) across in these images. Vesta was 131 million miles (211 kilometers) from Earth when Hubble made the observations.

The images show the difference in brightness and color on the asteroid's surface. These characteristics hint at the large-scale features that the Dawn spacecraft will see when it visits the potato-shaped asteroid.

Vesta is somewhat like our Moon, with ancient lava beds (the dark patches) and powdery debris, the pulverized remains of impacts (the orange-colored areas). The flattened area on one end of Vesta, visible in the top row of images, is a giant impact crater formed by a collision billions of years ago. The crater is 285 miles (460 kilometers) across, which is close to Vesta's roughly 330-mile (530-kilometer) diameter. Vesta is about the size of Arizona.

Astronomers used the images, taken with Hubble's Wide Field Camera 3, to better determine the orientation of Vesta's spin axis.

This will help scientists refine the Dawn spacecraft's orbit around the asteroid. Dawn will orbit the rocky object for a year, beginning in July 2011. The spacecraft then will travel to the dwarf planet Ceres, arriving in 2015.

Vesta is one of the largest of a reservoir of about 100,000 asteroids, the leftover material from the formation of our solar system's planets 4.6 billion years ago.

Hubble has kept its "eye" on Vesta for more than 15 years, beginning in 1994. Hubble images of Vesta in 1997 helped astronomers discover the asteroid's immense impact crater. Astronomers combined views of Vesta in near-ultraviolet and blue light to construct these images. The images were taken on Feb. 28, 2010.

These four Hubble Space Telescope images, taken over a five-month period, show the odd-shaped debris that likely came from a collision between two asteroids.

The Hubble images, taken from January to May 2010 with Wide Field Camera 3, reveal a point-like object about 400 feet (120 meters) wide, with a long, flowing dust tail behind a never-before-seen X pattern, which remained intact. Particle sizes in the tail are estimated to vary from about 1/25th of an inch (a millimeter) to an inch (2.5 centimeters) in diameter. The tail contains enough dust to make a ball 65 feet (20 meters) wide, most of it blown out of the bigger body by the impact-caused explosion.

The asteroid debris, dubbed P/2010 A2, appears to be shrinking in each successive image because Earth's faster orbit is carrying the planet away from the object. Between January and May, Earth rotated more than 100 million miles away from the debris field. The object was 102 million miles from Earth when Hubble first observed it in January 2010.

P/2010 A2 was found cruising around the asteroid belt, a reservoir of millions of rocky bodies between the orbits of Mars and Jupiter.

The images were taken in visible light and artificially colored blue.

These seven Hubble Space Telescope images, taken over a five-month period, show the odd-shaped debris from a collision between two asteroids.

The Hubble images, taken from January to May 2010 with Wide Field Camera 3, reveal a point-like object about 400 feet (120 meters) wide, with a long, flowing dust tail behind a never-before-seen X pattern. Particle sizes in the tail are estimated to vary from about 1/25th of an inch (a millimeter) to an inch (2.5 centimeters) in diameter. The tail contains enough dust to make a ball 65 feet (20 meters) wide, most of it blown out of the bigger body by the impact-caused explosion.

The asteroid debris, dubbed P/2010 A2, appears to be shrinking in each successive image because Earth's faster orbit is carrying the planet away from the object. Between January and May, Earth rotated more than 100 million miles away from the debris field. During the observations, the X pattern remained intact.

P/2010 A2 was found cruising around the asteroid belt, a reservoir of millions of rocky bodies between the orbits of Mars and Jupiter.

The images were taken in visible light and artificially colored blue.

Hubble Space Telescope observations of comet 103P/Hartley 2, taken on September 25, are helping in the planning for a November 4 flyby of the comet by NASA's Deep Impact eXtended Investigation (DIXI) on NASA's Deep Impact Spacecraft performing the EPOXI mission.

Analysis of the new Hubble data shows that the nucleus has a diameter of approximately 0.93 miles (1.5 kilometers), which is consistent with previous estimates.

The comet is in a highly active state as it approaches the Sun. The Hubble data show that the coma is remarkably uniform, with no evidence for the types of outgassing jets seen from most "Jupiter Family" comets, of which Hartley 2 is a member.

Jets can be produced when the dust emanates from a few specific icy regions, while most of the surface is covered with relatively inert, meteoritic-like material. In stark contrast, the activity from Hartley 2's nucleus appears to be more uniformly distributed over its entire surface, perhaps indicating a relatively "young" surface that hasn't yet been crusted over.

Hubble's spectrographs — the Cosmic Origins Spectrograph (COS) and the Space Telescope Imaging Spectrograph (STIS) — are expected to provide unique information about the comet's chemical composition that might not be obtainable any other way, including measurements by DIXI. The Hubble team is specifically searching for emissions from carbon monoxide (CO) and diatomic sulfur (S2). These molecules have been seen in other comets but have not yet been detected in 103P/Hartley 2.

103P/Hartley has an orbital period of 6.46 years. It was discovered by Malcolm Hartley in 1986 at the Schmidt Telescope Unit in Siding Spring, Australia. The comet will pass within 11 million miles of Earth (about 45 times the distance to the Moon) on October 20. During that time the comet may be visible to the naked eye as a 5th magnitude "fuzzy star" in the constellation Auriga.

For additional information, contact:

Ray Villard
Space Telescope Science Institute, Baltimore, Md.
410-338-4514
villard@stsci.edu

Hal Weaver
The Johns Hopkins University Applied Physics Laboratory, Laurel, Md.
443-778-8078
hal.weaver@jhuapl.edu

Though the universe is chock full of spiral-shaped galaxies, no two look exactly the same. This face-on spiral galaxy, called NGC 3982, is striking for its rich tapestry of star birth, along with its winding arms. The arms are lined with pink star-forming regions of glowing hydrogen, newborn blue star clusters, and obscuring dust lanes that provide the raw material for future generations of stars. The bright nucleus is home to an older population of stars, which grow ever more densely packed toward the center.

NGC 3982 is located about 68 million light-years away in the constellation Ursa Major. The galaxy spans about 30,000 light-years, one-third of the size of our Milky Way galaxy. This color image is composed of exposures taken by the Hubble Space Telescope's Wide Field Planetary Camera 2 (WFPC2), the Advanced Camera for Surveys (ACS), and the Wide Field Camera 3 (WFC3). The observations were taken between March 2000 and August 2009. The rich color range comes from the fact that the galaxy was photographed invisible and near-infrared light. Also used was a filter that isolates hydrogen emission that emanates from bright star-forming regions dotting the spiral arms.

This NASA Hubble Space Telescope image shows the distribution of dark matter in the center of the giant galaxy cluster Abell 1689, containing about 1,000 galaxies and trillions of stars.

Dark matter is an invisible form of matter that accounts for most of the universe's mass. Hubble cannot see the dark matter directly. Astronomers inferred its location by analyzing the effect of gravitational lensing, where light from galaxies behind Abell 1689 is distorted by intervening matter within the cluster.

Researchers used the observed positions of 135 lensed images of 42 background galaxies to calculate the location and amount of dark matter in the cluster. They superimposed a map of these inferred dark matter concentrations, tinted blue, on an image of the cluster taken by Hubble's Advanced Camera for Surveys. If the cluster's gravity came only from the visible galaxies, the lensing distortions would be much weaker. The map reveals that the densest concentration of dark matter is in the cluster's core.

Abell 1689 resides 2.2 billion light-years from Earth. The image was taken in June 2002.

These images, taken with NASA's Hubble Space Telescope, reveal fresh star birth in the ancient elliptical galaxy NGC 4150, located about 44 million light-years away.

The images combine observations taken in visible and near-ultraviolet light with Hubble's Wide Field Camera 3. Ultraviolet light traces the glow of young stars.

In the large-scale image, NGC 4150 looks very much like a typical elliptical galaxy. The dark strands of dust in the center, however, provide tentative evidence of a recent galaxy merger. The inset image shows a magnified view of the chaotic activity inside the galaxy's core. Those regions within about 650 light-years of the center that are not obscured by dust appear bright in near-ultraviolet light (shown here in blue). The blue areas indicate a flurry of recent star birth. The stellar breeding ground is about 1,300 light-years across. The stars in this area are less than a billion years old. By comparison, most of the stars in the galaxy are about 10 billion years old. These young stars most likely formed during an encounter with a smaller galaxy that was about one-twentieth the mass of NGC 4150.

The Hubble observations bolster the emerging view that ancient elliptical galaxies like NGC 4150 harbor a significant amount of recent, merger-driven star formation.

The images were taken Oct. 30 and Nov. 9, 2009.

In this image by NASA's Hubble Space Telescope, an unusual, ghostly green blob of gas appears to float near a normal-looking spiral galaxy.

The bizarre object, dubbed Hanny's Voorwerp (Hanny's Object in Dutch), is the only visible part of a 300,000-light-year-long streamer of gas stretching around the galaxy, called IC 2497. The greenish Voorwerp is visible because a searchlight beam of light from the galaxy's core illuminated it. This beam came from a quasar, a bright, energetic object that is powered by a black hole. The quasar may have turned off about 200,000 years ago.

This Hubble view uncovers a pocket of star clusters, the yellowish-orange area at the tip of Hanny's Voorwerp. The star clusters are confined to an area that is a few thousand light-years wide. The youngest stars are a couple of million years old. The Voorwerp is the size of our Milky Way galaxy, and its bright green color is from glowing oxygen.

Hubble also shows that gas flowing from IC 2497 may have instigated the star birth by compressing the gas in Hanny's Voorwerp. The galaxy is located about 650 million light-years from Earth.

What appears to be a gaping hole in Hanny's Voorwerp actually may be a shadow cast by an object in the quasar's light path. The feature gives the illusion of a hole about 20,000 light-years wide. Hubble reveals sharp edges but no other changes in the gas around the apparent opening, suggesting that an object close to the quasar may have blocked some of the light and projected a shadow on the Voorwerp. This phenomenon is similar to a fly on a movie projector lens casting a shadow on a movie screen.

An interaction between IC 2497 and another galaxy about a billion years ago may have created Hanny's Voorwerp and fueled the quasar. The Hubble image shows that IC 2497 has been disturbed, with complex dust patches, warped spiral arms, and regions of star formation around its core. These features suggest the aftermath of a galaxy merger. The bright spots in the central part of the galaxy are star-forming regions. The small, pinkish object to the lower right of IC 2497 is an edge-on spiral galaxy in the background.

The image was made by combining data from the Advanced Camera for Surveys (ACS) and the Wide Field Camera 3 (WFC3). The ACS exposures were taken April 12, 2010; the WFC3 data, April 4, 2010.

A vast number of galaxies is seen in this Hubble infrared image of the area surrounding the space oddity, Hanny's Voorwerp. Located in the constellation Leo Minor, a faint outline of the mysterious object, which is primarily visible in oxygen light, can be seen below the large galaxy IC 2497 near the center.

Leo Minor is known for its galaxy clusters, and this image is a testament to that fact. Most galaxies in this picture are spirals. Some are nearly face-on, as is the case with IC 2497 and its smaller companion to the left. Others are edge-on, as demonstrated by the multitude of elongated objects in the background.

This Hubble image was taken on April 4, 2010, with the Wide Field Camera 3 infrared detector. This near-infrared view of galaxies is typical of what is to come with the James Webb Space Telescope, whose prime purpose will be to image the universe in infrared wavelengths with high resolution.

These images by NASA's Hubble Space Telescope show off two dramatically different face-on views of the spiral galaxy M51, dubbed the Whirlpool Galaxy.

The image at left, taken in visible light, highlights the attributes of a typical spiral galaxy, including graceful, curving arms, pink star-forming regions, and brilliant blue strands of star clusters.

In the image at right, most of the starlight has been removed, revealing the Whirlpool's skeletal dust structure, as seen in near-infrared light. This new image is the sharpest view of the dense dust in M51. The narrow lanes of dust revealed by Hubble reflect the galaxy's moniker, the Whirlpool Galaxy, as if they were swirling toward the galaxy's core.

To map the galaxy's dust structure, researchers collected the galaxy's starlight by combining images taken in visible and near-infrared light. The visible-light image captured only some of the light; the rest was obscured by dust. The near-infrared view, however, revealed more starlight because near-infrared light penetrates dust. The researchers then subtracted the total amount of starlight from both images to see the galaxy's dust structure.

The red color in the near-infrared image traces the dust, which is punctuated by hundreds of tiny clumps of stars, each about 65 light-years wide. These stars have never been seen before. The star clusters cannot be seen in visible light because dense dust enshrouds them. The image reveals details as small as 35 light-years across.

Astronomers expected to see large dust clouds, ranging from about 100 light-years to more than 300 light-years wide. Instead, most of the dust is tied up in smooth and diffuse dust lanes. An encounter with another galaxy may have prevented giant clouds from forming.

Probing a galaxy's dust structure serves as an important diagnostic tool for astronomers, providing invaluable information on how the gas and dust collapse to form stars. Although Hubble is providing incisive views of the internal structure of galaxies such as M51, the planned James Webb Space Telescope (JWST) is expected to produce even crisper images.

Researchers constructed the image by combining visible-light exposures from Jan. 18 to 22, 2005, with the Advanced Camera for Surveys (ACS) and near-infrared–light pictures taken in December 2005 with the Near Infrared Camera and Multi-Object Spectrometer (NICMOS).

This is a color composite image of the Hubble Ultra Deep Field. Green circles mark the locations of candidate galaxies at a redshift of z~8, while higher-redshift candidates are circled in red. The estimated distances to these candidates have not been confirmed spectroscopically.

About 20 to 30 percent of these high-z galaxy candidates are very close to foreground galaxies, which is consistent with the prediction that a significant fraction of galaxies at very high redshifts are gravitationally lensed by individual foreground galaxies. This will help as a guide for future observations planned for the James Webb Space Telescope when it is launched.

The farthest and one of the very earliest galaxies ever seen in the universe appears as a faint red blob in this ultra-deep–field exposure taken with NASA's Hubble Space Telescope. This is the deepest infrared image taken of the universe. Based on the object's color, astronomers believe it is 13.2 billion light-years away.

The most distant objects in the universe appear extremely red because their light is stretched to longer, redder wavelengths by the expansion of the universe. This object is at an extremely faint magnitude of 29, which is 500 million times fainter that the faintest stars seen by the human eye.

The dim object is a compact galaxy of blue stars that existed 480 million years after the Big Bang, only four percent of the universe's current age. It is tiny and considered a building block of today's giant galaxies. Over one hundred such mini-galaxies would be needed to make up our Milky Way galaxy.

Follow-up spectroscopic observations with the planned James Webb Space Telescope later in this decade will be needed to definitively confirm the object's distance.

The Hubble Ultra Deep Field infrared exposures were taken in 2009 and 2010, and required a total of 111 orbits or 8 days of observing. The new Wide Field Camera 3 has the sharpness and near-infrared light sensitivity that matches the Advanced Camera for Surveys' optical images and allows for such a faint object to be selected from the thousands of other galaxies in the incredibly deep images of the Hubble Ultra Deep Field.

NASA's Hubble Space Telescope reveals a majestic disk of stars and dust lanes in this view of the spiral galaxy NGC 2841.

A bright cusp of starlight marks the galaxy's center. Spiraling outward are dust lanes that are silhouetted against the population of whitish middle-aged stars. Much younger blue stars trace the spiral arms.

Notably missing are pinkish emission nebulae indicative of new star birth. It is likely that the radiation and supersonic winds from fiery, super-hot, young blue stars cleared out the remaining gas (which glows pink), and hence shut down further star formation in the regions in which they were born. NGC 2841 currently has a relatively low star formation rate compared to other spirals that are ablaze with emission nebulae.

NGC 2841 lies 46 million light-years away in the constellation of Ursa Major (The Great Bear). This image was taken in 2010 through four different filters on Hubble's Wide Field Camera 3. Wavelengths range from ultraviolet light through visible light to near-infrared light.

The brilliant, blue glow of young stars traces the graceful spiral arms of galaxy NGC 5584 in this Hubble Space Telescope image. Thin, dark dust lanes appear to be flowing from the yellowish core, where older stars reside. The reddish dots sprinkled throughout the image are largely background galaxies.

Among the galaxy's myriad stars are pulsating stars called Cepheid variables and one recent Type Ia supernova, a special class of exploding stars. Astronomers use Cepheid variables and Type Ia supernovae as reliable distance markers to measure the universe's expansion rate. NGC 5584 was one of eight galaxies astronomers studied to measure the universe's expansion rate. In those galaxies, astronomers analyzed more than 600 Cepheid variables, including 250 in NGC 5584.

Cepheid variables pulsate at a rate matched closely by their intrinsic brightness, making them ideal for measuring distances to relatively nearby galaxies. Type Ia supernovae flare with the same brightness and are brilliant enough to be seen from relatively longer distances.

Astronomers search for Type Ia supernovae in nearby galaxies containing Cepheid variables so they can compare true brightness of both types of stars. They then use that information to calibrate the measurement of Type Ia supernovae in far-flung galaxies and calculate their distance from Earth. Once astronomers know accurate distances to galaxies near and far, they can determine the universe's expansion rate.

The image is a composite of several exposures taken in visible light between January and April 2010 with Hubble's Wide Field Camera 3.

NGC 5584 resides 72 million light-years away in the constellation Virgo.

This illustration shows the location of Cepheid variables found in the spiral galaxy NGC 5584. Ultraviolet, visible, and infrared data taken with Hubble's Wide Field Camera 3 in 2010 reveal Cepheids of varying periods. Those stars with periods of less than 30 days and between 30 and 60 days are marked with green and blue circles, respectively. A small number of Cepheids, with periods larger than 60 days, are marked in red.