COBE Satellite Marks 20th Anniversary

NASA’s Cosmic Background Explorer (COBE) satellite rocketed into Earth orbit on Nov. 18, 1989, and quickly revolutionized our understanding of the early cosmos. Developed and built at Goddard Space Flight Center in Greenbelt, Md., COBE precisely measured and mapped the oldest light in the universe — the cosmic microwave background. COBE showed that the radiation's spectrum agrees exactly with