COBE (Cosmic Background Explorer)

Technicians work on the COBE spacecraft in a clean room at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. The mission launched into an Earth orbit in 1989 to make an all-sky map of the cosmic microwave background, the oldest light in the universe. The conical silver shield protects the scientific instruments from direct radiation from the Sun and Earth, isolates them from radio-frequency interference from the spacecraft transmitters and terrestrial sources, and provides thermal isolation for a dewar containing liquid helium coolant.