Cosmic Background Explorer (COBE), U.S. satellite placed in Earth orbit in 1989 to map the “smoothness” of the cosmic background radiation field and, by extension, to confirm the validity of the big bang theory of the origin of the universe.
WMAP measures anisotropy* with much finer detail and greater sensitivity than COBE did. These measurements reveal the size, matter content, age, geometry and fate of the universe. They also reveal the primordial structure that grew to form galaxies and will test ideas about the origins of these primordial structures.
