... Calibration and analysis of this observation posed very interesting challenges for the authors, in particular dealing with an exciting new instrument whose on-orbit calibration was not yet well defined. ... Five mosaic positions were observed during five consecutive orbits as well as observations for dark and flat calibration. ... Darks and flats had to be created from contemporaneous reference observations and problems within the calibration process had to be resolved. ...

... 2002 February 4 . Comet LINEAR (WM1) Shines in the South . ... Explanation: A new comet has brightened unexpectedly and is currently visible to unaided observers of southern skies. Comet C/2000 WM1 (LINEAR) is now reported by some observers to be at third magnitude , making it brighter -- although more diffuse -- than most visible stars. ... Pictured above is the center of Comet LINEAR (WM1) taken the morning of February 1 from 300 km north of Sydney, Australia . ... About APOD | ...

... Copyrightї1997 Bob Yen (byen@ix.netcom.com) (http://www.comet-track.com/hb/hb.html) . ... Information on Comet Hale-Bopp for the Non-Astronomer Hale-Bopp rotates about twice a day (3/14/97) . ... The Comet Observation Home Page was been selected to receive the Griffith Observatory Star Award for the week of February 2 - 8, 1997 for excellence in promoting astronomy to the public through the World Wide Web. ... Typically, about 1,000 individual users/computers access this page every day. ...

home publications > mercury . ... Astronomy Beat . ... Nearly four centuries ago, Galileo's simple observations of Earth's planetary sibling, Venus, buoyed the proponents of a Copernican universe. ... The Italian astronomer had settled into a new house in Florence and had begun to observe Venus, which in November 1610 would have appeared as an evening star, bright in the western sky after dusk. ... From these two observations, Galileo inferred that Venus must orbit closer to the Sun than does Earth. ...

... Tonight's Sky . ... The Magazine . News . Observing . ... Magazine . ... Gravitational wave search provides insights into galaxy evolution and mergers . ... The double star 54 Leonis, spiral galaxy NGC 3198, and emission nebula NGC 3199 . ... Open cluster NGC 2818, spiral galaxy NGC 2964, and spiral galaxy NGC 2976 . ... Astronomy for Kids . ... February 2006 . ... Receive news, sky-event information, observing tips, and more from Astronomy's weekly email newsletter. ... Astronomy Magazine . ...