... December 15, 1998 . Plains and Ridges on Europa . Credit: Galileo Project , JPL , NASA . Explanation: The ridges on Europa may be caused by cold water volcanoes. Europa , one of the largest moons of Jupiter , has been the source of intense scrutiny since speculation increased of there being oceans beneath its icy surface . ... The above image highlights features common to Europa's surface : pure blue water ice beneath lighter ridges that run for many kilometers. ... About APOD > . ...

... 2000 December 15 . IC443's Neutron Star . ... Explanation: Using x-ray data from the orbiting Chandra Observatory along with radio data from the Very Large Array , a team of researchers has discovered evidence for a new example of one of the most bizarre objects known to modern astrophysics -- a neutron star . ... The core collapsed when the star, located a reassuring 5,000 light-years away in the constellation Gemini , exploded long ago. How long ago? ... About APOD | ... NASA Technical Rep.: ...

Supernova 2002cr and 2002ed in NGC 5468 . This page is devoted to information on Supernova 2002cr and Supernova 2002ed in NGC 5468 Basic information on this SN, including the last reported brightness, on this Supernova can be found on the main page . ... 2002/05/02.39 . ... Rafael Ferrando image . ... J. Nicolas image . ... Image comparing 2002ed, 2002cr, and 1999cp , local mirror Light curves and Spectra: . ... vsnet-campaign-sn 453 ] SN 2002ed in NGC 5468, the host galaxy of SN 2002cr . ...

... At present, he is a Leading researcher at the Department of Non-Stationary Stars and Stellar Spectroscopy, heading the group of the General Catalogue of Variable Stars, and a Leading researcher at the Department of Variable Stars and Galactic Astronomy of the Sternberg Astronomical Institute, heading the group of Variable Stars. ... P.P. Parenago, B.V. Kukarkin, P.N. Kholopov leaded the team of variable star catalogue compilers at Astronomical Council/INASAN and at Sternberg Institute through years....

... Here is a brief outline of the current theory of the events in the early history of the solar system: . A cloud of interstellar gas and/or dust (the "solar nebula") is disturbed and collapses under its own gravity. ... The gas cools off enough for the metal, rock and (far enough from the forming star) ice to condense out into tiny particles. (i.e. some of the gas turns back into dust). ... Once the larger of these particles get big enough to have a nontrivial gravity, their growth accelerates. ...