US astronaut. He was on four space shuttle flights, during which he made two space walks and logged 847 hours in space. He was a member of the crew of Atlantis in April 1991 that deployed the Gamma-Ray Observatory, flight engineer of Endeavour in September 1992 on a cooperative mission with Japan, commander of Endeavour in April 1994, mapping Earth's air pollution, and served aboard Atlantis in September 1996, docking with Russia's Mir space station. He joined NASA in 1980 and was a flight controller for shuttle payload operations when selected as an astronaut in 1985. He left NASA in 2001.
Subjects: Astronomy and Astrophysics.