... Europa: The Latest From Galileo . ... Black Hole Signature From Advective Disks . ... If alone, a black hole would indeed appear quite black, but many black hole candidates are part of binary star systems. ... These spots appear dark in photographs like the one above, but in fact sunspots are quite bright - they are just dark compared to the rest of the Sun. Sunspots are about the size of the Earth and frequently occur in groups, as shown above. Mercury in Stereo: Craters Within Craters . ...

... Gift Center . ... Why do aurorae appear strongest within rings centered on Earth's poles instead of filled-in circles? ... RELATED TOPICS: AURORAE . The visible aurorae result from electrons that move along magnetic field lines from space into the upper atmosphere. ... Just make sure you're registered with the website. Get instant access to subscriber content on Astronomy.com! ... If you are already registered on Astronomy.com, please log in below. ...

... 2013 December 1 . A Laser Strike at the Galactic Center . ... Explanation: Why are these people shooting a powerful laser into the center of our Galaxy? ... Constant imaging of high-altitude atoms excited by the laser -- which appear like an artificial star -- allow astronomers to instantly measure atmospheric blurring . ... In this case , a VLT was observing our Galaxy's center , and so Earth's atmospheric blurring in that direction was needed. ... About APOD | ...

. " The Arecibo Observatory is sponsored by the National Science Foundation. Any opinions, findings and conclusions or recommendations . expressed in this publication are those of the author(s) and do not necessarily reflect the views of the National Science Foundation."

... 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. ...

... 2000 December 20 . Sgr A*: Fast Stars Near the Galactic Center . ... Explanation: Why are these stars moving so fast? Shown above is a time-lapse movie in infrared light detailing how stars in the central light-year of our Galaxy have moved over the past eight years. ... If these fast stars are held to the Galactic Center by gravity, then the central object exerting this gravity must be both compact and massive. ... About APOD | ...

... Home Observing Lincoln Center . ... AAA Fall Astronomy Class: Astronomy Basics тАУ October-November 2015 . ... This MonthтАЩs Sky тАУ April 2015 . This MonthтАЩs Sky тАУ May 2015 . This MonthтАЩs Sky тАУ June 2015 . ... Beyond New York City . ... Observing Resources for Amateur Astronomers - Part 1: Beginning Observers . ... A History of the First Forty Years of the Amateur Astronomers Association . ... 2016 Amateur Astronomers Association of New York Designed by Press Customizr Powered by . ...

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. ...

... НЕПРЕРЫВНОГО МАТЕМАТИЧЕСКОГО ОБРАЗОВАНИЯ . ... Кружок ?Олимпиады и математика? ... Московская математическая олимпиада . Заочный математический конкурс . ... Устные математические олимпиады . Олимпиады по программированию . Математический праздник . Математические регаты . ... Математические бои . Олимпиада по геометрии им. И.Ф.Шарыгина . ... Программа ?Math in Moscow? Научные конкурсы . Творческий конкурс . ... График олимпиад . ... XXVII Математический праздник . ...

... In summer 1994, the biggest news in astronomy was the collision of comet Shoemaker-Levy 9 with Jupiter. During this school year, Jupiter will charge back into the limelight with the arrival of the Galileo spacecraft (see figure 8 ). On Dec. 7, following a tortuous six-year ramble through the solar system, Galileo will begin its two-year mission studying Jupiter and its gaggle of moons. ... Besides the camera, Galileo will carry instruments capable of identifying minerals on Jupiter's moons. ...

... Институт прикладной математики им. М.В.Келдыша . БАЛЛИСТИЧЕСКИЙ ЦЕНТР . О Центре . ... Баллистический Центр Института прикладной математики им. М.В.Келдыша РАН . Баллистический центр (БЦ) ИПМ им. М.В. Келдыша создан по предложению С.П. Королева и М.В. Келдыша в 1965 году. На него были возложены работы по баллистико-навигационному обеспечению (БНО) управления полетом пилотируемых кораблей и автоматических космических аппаратов научного и народно-хозяйственного назначения. ...

... Armagh Observatory, College Hill, Armagh BT61 9DG, +44 (0)28 3752 2928 . ... Although the comet itself never comes dangerously close to the Earth, the particles of dust that it has shed during its many past passages through perihelion found their way into the Earth's atmosphere, appearing as meteors in the cold December sky. ... Animation 1 . ... An Ursid meteor captured by the Armagh Observatory's NE-facing meteor camera in the early morning of 23rd December. ... Meteor Showers Online . ...

M1 image More About M1 Nice Color Picture . ... M16 image More About M16 HST image . ... M31 image More About M31 Nice Color Picture . ... M42 image ; M43 image More About M42/43 Nice Color CCD Picture . M51 image More About M51 Color Image of M51 M51 Supernova . M57 image More About M57 Nice Color CCD Picture Very Deep M57 Image . ... M81 image More About M81 M81 Supernova Ultraviolet Image of M81 More about Ultraviolet Imaging . M82 image More About M82 M82 False Color M82 True Color . ...

EMBARGOED UNTIL: 9:20 AM CST, January 6, 1999 CONTACT: John Biretta Space Telecsope Science Institute, Baltimore, MD (Phone: (410) 338-4917; Internet: biretta@stsci.edu) HUBBLE DETECTS FASTER-THAN-LIGHT MOTION IN GALAXY M87 Astronomers reported today discovering clouds which appear to move many times faster than the speed of light, shooting out from the region of a black hole at the center of the M87 galaxy. ... It's an illusion created by the finite speed of light and rapid motion," Biretta said. ...

... Observations . ... Natural Satellites Data Center. ... Nomenclature of satellites | ... Inner satellites of Jupiter . ... Inner satellites . Mutual events of the Galileans . ... Inner satellites of Saturn . Main satellites of Saturn . ... Mutual events of the main satellites . Inner satellites of Uranus . Main satellites of Uranus . ... Mutual events of the Uranian satellites . Inner satellites of Neptune . Main satellites of Neptune . Outer satellites of Neptune . ...

... 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). ...

... SAO researchers have discovered that supercritical accretion disks eject hot gas with a velocity of a few thousand kilometers per second. The supercritical regime of accretion onto black holes is very important for astrophysics. In the first half-billion years just after our Universe was born, supermassive black holes (quasars) began to appear and grow in centers of young galaxies. ... Gas falling onto a black hole (accretion) is not a frequent phenomenon in our Galaxy. ...

... Universal time of geocentric opposition h m s in right ascension 2009, December 31, 19 04 46.9 Sun Moon h m s h m s Right ascension . ... 16 15.92 16 36.60 Circumstances of the Eclipse Position Angles of the Moon's axis h m o Moon enters penumbra . December 31, 17 15.3 2.44 Moon enters umbra . ... 62 55.3 E Magnitude of the eclipse 0.080 " Angular radius of the penumbra 4735.00 " Angular radius of the umbra 2744.39 ------------------------------------------------------------------------------- | ...