Astronomy Picture of the Day . ... The View Near a Black Hole . ... Studies of the bright light emitted by the swirling gas frequently indicate not only that a black hole is present, but also likely attributes. ... Medieval Astronomy from Melk Abbey . ... The intriguing page.. Castle and Full Moon . ... Exactly full on April 9 at 1456 UT, it followed the March equinox, making it the first Full Moon of spring in the north and autumn in the southern hemisphere. ... First page ] Prev. ... April . ...

... Bad Astronomy . ... Bitesize Astronomy . ... Last week's Snack talked about how black holes can affect the environment around them in such a way as to be very bright . ... It's a common misconception that black holes always have matter swirling into them. ... As this matter gets closer and closer to the black hole it piles up and a large, fairly flat disk forms. This is called the accretion disk , because matter from this disk accretes (that is, falls in) on the black hole. ... 2008 Phil Plait. ...

... ESO is building what will be the World's largest optical telescope array, The Very Large Telescope (VLT). The VLT Project organisation is responsible for the design and construction of the Unit Telescopes, including enclosures, optics, adapter-rotators and coating unit. ... Unit Telescopes Overview - This page is outdated, an update is in process. ... Secondary mirror (M2 Unit) - This page is outdated, an update is in process. ... Coating Unit - This page is outdated, an update is in process. ...

... Planets . ... Earth Satellites . ... Looking in the direction of the constellation Cygnus the Swan and launched by NASA in 2009 is the Kepler Space Observatory.Many previous missions searching for exoplanets mainly detected large giant planets, like large hot Jupiters (it is easier to detect larger planets).However KeplerтАЩs main objective is to search for much smaller planets located in a habitable zone which is not too close nor too far from their star; planets which may be just like our Earth. ...

... 2008 December 19 . The Large Cloud of Magellan . ... As a result, two fuzzy cloud-like objects easily visible to southern hemisphere skygazers are known as the Clouds of Magellan , now understood to be satellite galaxies of our much larger, spiral Milky Way galaxy. About 160,000 light-years distant in the constellation Dorado , the Large Magellanic Cloud (LMC) is seen here in a remarkably detailed, 10 frame mosaic image . ... About APOD | ... NASA Web Privacy Policy and Important Notices . ...

... The TRACE images may be used without restrictions in publications of any kind. ... These two images, taken on 18 November 2000 at 15:54UT and 16:11UT, respectively, show such an event: the red circle in the image to the left shows a region where many loops are cooling, with bright loop tops (the intensity scales with the square root of the image to reduce the dynamic range). ... See also a collection of images related to the Sun, other cool stars, and solar-terrestrial effects . ... Images | ...

You Can Make Stellar Images Brighter . Articles | ... A few months ago I wrote an article titled "You Can’t Make Them Brighter". So why am I now writing that you can make them brighter. ... The image of a focused star is actually a small disk called the Airy disk, named after the 19 th century scientist Sir George Airy. ... For a given aperture, a smaller Airy disk means that the light is focused to a smaller disk and is therefore brighter. ... www.astronomy.net . About Astronomy Net | ...

... 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: . ...

In this gallery are many images of Low Surface Brightness Galaxies which have recently been discovered and analyzed. ... The central surface brightness of this galaxy is 24.28 . Malin 2 This galaxy is another huge disk galaxy with a scale length of 15 kpc and a redshift of 15000 km/a. The high surface brightness knot in one of its spiral arms actually has the same color, luminosity and H-alpha equivalent width as the entire Large Magellanic Cloud . ... Truly it is a Low Surface Brightness Galaxy. ...

... Near Infrared Camera and Multi-Object Spectrometer Instrument Handbook for Cycle 17 > Chapter 4: Imaging > 4.6 Photon and Cosmic Ray Persistence . ... HgCdTe detector arrays like those in NICMOS are subject to image persistence. ... Experiments using Cycle 7 NICMOS data have shown that it is possible to scale and subtract such ?post-SAA darks? from subsequent science exposures taken later in the same orbit, and thus to remove a significant fraction of the CR persistence signal. ...

Because they are so distant from Earth, Centaurs appear as pinpricks of light in even the largest telescopes. Saturn's 200 kilometer moon Phoebe, depicted in this image, seems likely to be a Centaur that was captured by that planet's gravity at some time in the past. ... NASA s New Horizons spacecraft, having flown past Pluto six months ago, has been targeted to conduct an approach to a 45-kilometer-wide trans-Neptunian object at the end of 2018. NASA/JPL-Caltech/Space Science Institute ...

Ganymede . ... Ganymede Statistics . ... Hubble Finds Ozone on Jupiter's Moon Ganymede . ... Like Callisto , Ganymede is most likely composed of a rocky core with a water/ice mantle and a crust of rock and ice. ... Ganymede's mantle is most likely composed of ice and silicates, and its crust is probably a thick layer of water ice. ... Ganymede's surface is rich in water ice and Voyager and Galileo images show features which are evidence of geological and tectonic disruption of the surface in the past. ...

... Armagh Observatory, College Hill, Armagh BT61 9DG, +44 (0)28 3752 2928 . Armagh Observatory, 1st December 2015: This year s Geminid meteor display, the best of the annual meteor showers, will be visible from approximately the 7th to 17th December, peaking on the evening of the 14th. ... Unlike most meteor showers, however, which originate from dust grains ejected into space by comets, the Geminid meteors originate from an unusual near-Earth asteroid, namely (3200) Phaethon. ...

Some time in dec01 a large ripple appeared in the gregorian dome 430 Mhz data. ... While debugging the problem, it was discovered that turning on the gregorian dome motors caused the ripple to appear. ... The figures show the birdie and the ripple. ... Turning the motors on may have caused some vibrations (although you didn't have to move the dome for the modulation to appear) or the motors turning on could have caused the voltage to sag a bit causing the tone to switch to a modulated wave form. ...

Check out the new images (Jan 18-25) and (Jan 26-Feb 05) of the comet by Rob McNaught. ... Every few years a comet becomes bright enough to be easily seen with the naked eye but only every decade or so are these comparable with comets like Halley. ... Before Jan 13, the comet is not visible in the Australian sky after sunset. ... SOHO images . ... On Jan 12 at approximately 09:00 UT (8pm NSW time), comet C/2006 P1 McNaught appears at the 11 o'clock position in the images. ... STEREO images . ...

... From the chain visibility point of view, it is very recommended to look at the Javascript movies , especially if the frame rate can be not regulated in your MPEG player. ... The non-CH-associated large-scale chains visible on the SOHO/EIT images at three wavelengths of 171, 195 and 284 as well as on the MLSO/HAO He I 10830 spectroheliogram of December 16, 1997. ... The SOHO/EIT movies at 171 and 195 show the chain dynamics on June 1-3, 1998. ... Javascript movie (230 KB), SOHO/EIT, 171 . ...

... Baffled, you turn to the waiter. ... The waiter smiles. ... Some prefer small stars while others insist that the larger they are the better they are. ... Of course," he adds, sensing your concern, "you are the guest of Chez Stella. ... Immediately you hear the "tock... tock... tock" of the stopwatch, and you gaze deep into the distant star. ... You hadn't noticed before, but it is giving off vast symmetric clouds of what looks like smoke or dust hanging in the space around the beautiful star. ...

Next: Ejectors in Massive Binary Previous: Artificial Galaxy: Full Matrix . The first version of the Scenario Machine was aimed especially at the simulation of massive binary star evolution. ... First, there is a large class of intermediate mass binaries (say, consisting initially of 8 + 5 solar masses) that can also produce NS and thus lead to the formation of a bright X-ray source. ... Next: Ejectors in Massive Binary Previous: Artificial Galaxy: Full Matrix Mike E. Prokhorov . ...

... Users . ... Data Collection and Analysis . ... This particular part of the analysis has been disabled since the code is struggling to cope with the number of users seen this year, in particular the large contingent of people who have re-tweeted NASA. ... Order accounts: by user number (effectively random) by number of tweets (includes retweets) by number of followers by number of followers that also tweeted about AAS225 by number of friends that also tweeted about AAS225 . ... by user number . ...

... Today this year's largest group of sunspots will cross the Sun's central meridian. ... The next day, the number of spots in the group reached five, and the day after, on June 2nd, it was possible to count thirteen sunspots on solar disk, which had been clear prior to this. ... This year's two most powerful active areas, which passed across the solar disk at the beginning of May, 2009, are set to appear in the Sun's eastern sector in two days, on June 6th. ...