US astronaut. His three space shuttle flights include the Discovery mission in February 1997 to service the Hubble Space Telescope. During the mission he made two space walks. He logged more than 742 hours in space and 33 hours of space walks. He was assigned to a 2004 flight that was postponed following the Columbia space shuttle disaster the previous year. Tanner joined NASA's Johnson Space Center in 1984 as an aerospace engineer and research pilot. He was selected as an astronaut in 1992.
Subjects: Astronomy and Astrophysics.