US astronaut. Selected in 1966 for a potential Apollo mission, McCandless did not travel to space until February 1984 as a mission specialist on the space shuttle Challenger. He helped develop the manned manoeuvring unit, which he used to become the first person to fly as an independent satellite during a space walk on the mission. His other space shuttle flight was in Discovery, launched in April 1990 to deploy the Hubble Space Telescope.
Subjects: Astronomy and Astrophysics.