He also flew with the first servicing and repair mission to the Hubble Space Telescope on the space shuttle Endeavour in December 1993. Musgrave was selected as an astronaut in 1967 and retired from NASA in 1997. He logged more than 1280 hours in space on six flights, including the first mission of the Challenger space shuttle in April 1983. In 1996 he became only the second astronaut to fly on six space flights, and he is the most formally educated astronaut, with six academic degrees.