Artist's impression of COBE, NASA's Cosmic Background Explorer satellite. Launched on 18 November 1989, COBE is a fundamental astronomy mission to investigate the cosmic background radiation & answer questions about the nature of the Universe as a whole. It is equipped with infrared & microwave sensors which will map the whole sky at 100 different wavelengths. In 1990, COBE returned the first spectrum of the cosmic background radiation - the heat signal" of the Big Bang - & showed it to be a perfect "black body" curve, so confirming the theory of the Big Bang. The picture represents COBE against the glow of the cosmic background radiation."