Astronaut who served on several Space Shuttle missions including a 128-day mission aboard the Russian space station Mir.
He received his medical degree from Indiana University and worked as a flight surgeon in the U.S. Air Force.
He began his work with NASA in the engineering and medical science division at the Johnson Space Center in Texas.
He married Tammy Kruse.
He and Kenneth Cockrell were both members of NASA Astronaut Group 13 in 1990.