Astronomy Picture of the Day . GL 229B: An Elusive Brown Dwarf? ... A leading candidate is a type of dim, low mass star called a "brown dwarf" star. ... In the center of the above photograph lies a star with one of the hottest surface temperatures yet confirmed. ... Releasing Compton . ... Named for Nobel laureate physicist Arthur Holly Compton, the Compton Gamma Ray Observatory (CGRO) Satellite was launched in April of 1991 aboard the Space Shuttle Atlantis. ... Too Close to a Black Hole . ...