Mission Archive

NASA · 1999

High Earth orbit

The third of NASA's Great Observatories, an X-ray telescope with the sharpest vision of any yet flown. It studies black holes, supernova remnants and the hot gas in galaxy clusters.

NASA · 1991

Low Earth orbit

The second of NASA's Great Observatories, which studied the Universe in gamma rays and showed that gamma-ray bursts come from all directions in the sky. At 17 tonnes it was the heaviest astrophysics payload flown at the time.

NASA · 1973

Jupiter, Saturn

The second spacecraft to fly past Jupiter and the first to reach Saturn, passing within 21,000 km of its cloud tops in 1979.

NASA · 1972

Jupiter

The first spacecraft to cross the asteroid belt and fly past Jupiter, and the first sent on a path out of the Solar System.