September 2002: As SIRTF gathers infrared light into its three scientific instruments, its two-tone color scheme is hard at work. The side of SIRTF that faces the Sun is painted a reflective color, to bounce as much of the Sun's heat as possible off of the heat-sensitive telescope. Meanwhile, the other side of the telescope is painted black, because black is the best color for radiating the heat that SIRTF does pick up off into space. In order to be effective, the telescope needs to operate at an extremely cold temperature, only a few degrees above absolute zero!