... IC 4406: A Seemingly Square Nebula . ... How can a round star make a square nebula? ... Like a butterfly, a white dwarf star begins its life by casting off a cocoon that enclosed its former self. ... A massive star ends life as a supernova, blasting its outer layers back to interstellar space. ... Three Dusty Stars . ... These separate radio images reveal three dusty debris disks surrounding three bright, young, nearby stars - evidence for solar systems in formation. ... Water From Orion . ...

... Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. 2001 December 25 . Star Forming Region Hubble-V . ... Hubble Heritage Team , NASA . ... Inspection of NGC 6822 shows several bright star groups, including two dubbed Hubble-X and Hubble-V. Pictured above , the Hubble Space Telescope has resolved Hubble V into the energetic stars that are lighting up the surrounding gas. ... About APOD | ...

... HST . ... Data . ... HST Overview . Overview . ... Retrieving HST Data . ... This FORM is a quick tool for flux conversion between diverse unit systems. ... INPUT FLUX or MAGNITUDE UNITS CLEAR Jy W/m2/Hz W/m2/um W/cm2/um erg/cm2/s/Hz erg/cm2/s/A photons/m2/w/um photons/cm2/s/A AB magnitude magnitude V magnitude U magnitude B magnitude R magnitude I magnitude J magnitude H magnitude K magnitude L magnitude L1 magnitude M magnitude N magnitude Q . ... Enter the Input Flux or Magnitude Value : . ...

... Tonight's Sky . ... The Magazine . ... Observing . ... The double star 54 Leonis, spiral galaxy NGC 3198, and emission nebula NGC 3199 . ... Astronomy for Kids . ... Observing springtime deep-sky objects with a large telescope . ... Bright planets meet at dusk . ... Astronomy magazine subscribers can read the full article for free. ... Get instant access to subscriber content on Astronomy.com! ... Receive news, sky-event information, observing tips, and more from Astronomy's weekly email newsletter....

... STScI-PRC00-10 "HUBBLE TAKES A CLOSE-UP VIEW OF A REFLECTION NEBULA IN ORION" Just weeks after NASA astronauts repaired the Hubble Space Telescope in December 1999, the Hubble Heritage Project snapped this picture of NGC 1999, a nebula in the constellation Orion. ... NGC 1999 is an example of a reflection nebula. ... The star is so young that it is still surrounded by a cloud of material left over from its formation, here seen as the NGC 1999 reflection nebula. ...

... STScI-PRC95-45a CRUCIBLE OF CREATION: PANORAMIC HUBBLE MOSAIC ZOOMS IN ON MAELSTROM OF STAR BIRTH This spectacular color panorama of the center the Orion nebula is one of the largest pictures ever assembled from individual images taken with NASA's Hubble Space Telescope. ... Though this 2.5 light-years wide view is still a small portion of the entire nebula, it includes almost all of the light from the bright glowing clouds of gas and a star cluster associated with the nebula. ...

Photon Scattering: Basic Principle of Photon Scattering . Audio Narration is available . No Scattering: Photon Source and Detector . ... For optical photons, scattering goes as wavelength to the -4 power. In the case of blue photons compared to red photons, this means that blue photons are about 10 times more likely to get scattered than red photons. ... Watch the blue photons scatter away from the detector . ... Interstellar dust make stars appear redder than they really are . ...

... The European HST Archive has been moved to ESA's European Space Astronomy Centre ( ESAC ), Spain, where most of ESA's Space Science Archives are located and operated from. ... The Space Telescope European Coordinating Facility (ST-ECF), jointly operated by ESA and the European Southern Observatory ( ESO ) was, until the end of 2010, the European HST science facility, supporting the European astronomy community in exploiting the research opportunities provided by the Hubble Space Telescope. ...

Astronotes Armagh Planetarium's Stellar Blog! ... Stars . ... Monthly Sky Notes . ... This month Jupiter the largest of all planets, remains visible in the sky after sunset, not setting until after 11pm.€а On the evening of 12and 13 December the bright star-like object close to the Moon will be this gas giant planet. ... Rising this month is the great winter constellation of Orion the Hunter who will remain in our night sky through until March. ... Tweets that mention Wonders of the December Sky | ...

... Gallery . ... Wide Field Survey Images . Miscellaneous Wide Field Images . Orion Nebula by the Hubble Space Telescope . Sidebar Left . Sidebar Top . ... Title: Orion Nebula by the Hubble Space Telescope . Description: NOTE: All images are copyright and must not be reproduced or mirrored in any form without written permission. ... Orion Nebula by the Hubble Space Telescope NOTE: All images are copyright and must not be reproduced or mirrored in any form without written permission. ...

... International Year of Astronomy in Ireland . ... Christmas Moon", painting by Miruna Popescu, Armagh Observatory, featured as " Lunar photo of the Day " and " Astronomy Sketch of the Day " on 25 December 2009. ... To mark the 400th anniversary of GalileoтАЩs first use of the telescope to observe the sky, 2009 has been celebrated worldwide as the International Year of Astronomy. Moon over Armagh - link to Astronomy Sketch of the Day on 25 December 2009 . ... Monday, 11 May 2009 23:54 . ...

... Science User Portal . ... ESO, the European Southern Observatory . ... Travel and Contacts . Travel to ESO Headquarters . ... Survey Telescopes . ... Star Clusters . ... FLAMES . ... 100 Hours of Astronomy . ... IMAX€о 3D Film Hidden Universe . ... This image, the first to be released publicly from VISTA, the worldтАЩs largest survey telescope, shows the spectacular star-forming region known as the Flame Nebula, or NGC 2024, in the constellation of Orion (the Hunter) and its surroundings. ...

... Dept. for Astrometry & Space Geodynamics . ... Dept. for Physics of Stars&Galaxies . ... Dept. for Physics of Planetary Systems . ... Science . ... All Pages . ... Research of the stars with planets which pass apparent star disk (transiting exoplanets). The transit method based on a detection star brightness decrease during a passing of planet in front of its disk. Observed brightness system decries when planet pass star disk and its volume depend of the relative sizes star and planet. ...

Class 1 Introduction, Background History of Modern Astronomy The Night Sky, Eclipses and the Seasons Kepler's Laws Newtonian Gravity General Relativity Matter and Light Telescopes Class 2 Solar System Characteristics Formation Exosolar Planets Class 3 Stars The Sun Stellar Evolution of Low and High Mass Stars Deaths of Stars Exotic Stars Class 4 Galaxies Galaxy Classification Formation of Galaxies Galactic Evolution ... So far, one planet has been studied by this method. ...

National Aeronautics and Space Administration . ... Carl E. Walz (Colonel, USAF, Ret.) NASA ASTRONAUT (FORMER) . ... NASA EXPERIENCE: Selected by NASA in January 1990, Walz is a veteran of four space flights, and has logged a total of 231 days in space. He was a mission specialist on STS-51 (1993), was the Orbiter flight engineer (MS-2) on STS-65 (1994), was a mission specialist on STS-79 (1996), and served 196 days in space as flight engineer (FE-1) on ISS Expedition-Four (2001-2002). ...

... The expansion is measured as a number called the Hubble Constant . ... Our value is about 20% lower than the one got with the Hubble Space Telescope in 1994," said Dr Jim Lovell, leader of the team that made the measurement. The Hubble Constant is named after American astronomer Edwin Hubble, who in the 1920s found that other galaxies were moving away from ours. ... The Hubble Constant links the galaxy's distance with its speed." ... A short run-down on the Hubble Constant: . ...

... V838 Mon is a member of a new class of eruptive variables which appear as a peculiar novae having late K-M type spectra in their outburst. Before its outburst, it was a wide binary system of B3V type stars. ... The B3V companion was seen in the outburst in the UV spectrum taken with HST (Rauch et al., ... In the latest spectra, the light of B3V companion was predominating in the short-wave photometric bands. ... CCD blue frames of V838 Mon before the eclipse (left) and in the eclipse (right). ...

... Its perihelion would occur on April 1, 1997, at which point the comet would be only 0.92 astronomical units from the Sun, just within the orbit of Earth. ... Taken in April 1993, the photo showed the comet over 13 astronomical units from the Sun, well beyond the orbit of Saturn. ... Hale, as in Comet Hale-Bopp, has written a book, Everybody's Comet (available through the ASP Catalog) and coordinated an Internet project, "Hale-Bopp: Live in the American Classroom." ... Anatomy of a comet. ...

... The Galactic low-mass X-ray binary GS 2023+338 was discovered during the burst on May 22, 1989 with the Japanise satellite Ginga (aka Galaxy). The flux reached 17 crabs (this unit of flux measurement is an bright X-ray source, Crab Nebula) at 10-35 keV. ... No other radio telescope worldwide carried out multi-frequency measurements. ... Upon 14 days the radio flux fell below the detection level at the RATAN-600 in relation to the decrease of the X-ray flux. ...

... Crescent Nebula . ... Above the Crescent are the Lynd's Bright Nebulae LBN 215, to the right is the filamentary LBN 208 and below is LBN 193. Hubble Palette, 5 nm Narrowband filters, S-II (Red Channel): H-alpha (Green Channel): O-III (Blue Channel) - 30: 55: 40 minutes, 5 minute subframe, binned 1x1, Total= 125 minutes, Takahashi Epsilon-180, SBIG STL-6303E CCD camera, ATMoB Clubhouse, Westford, MA, 13 August 2010. ... Copyright (c) Amateur Telescope Makers of Boston, Inc. ...