April 5, 1991 – The Space Shuttle Atlantis launches from Cape Canaveral, Florida on its eighth mission, STS-37. The Atlantis’s crew launched the Compton Gamma Ray Observatory, part of the Great Observatory program that included the Hubble Telescope. Two of the crew members, Jerry Ross and Jerome Apt, performed two EVAs, the first scheduled and unscheduled EVAs since 1985.

Read more about the STS-37 mission and its crew.