A retired NASA astronaut who flew on three space shuttle missions: STS-72 (Endeavour), STS-96 (Discovery), and STS-105 (Discovery).
Married to Susan R. Barry, a professor of neurobiology at Mount Holyoke College and the author of the autobiographical book "Fixing My Gaze: A Scientist's Journey into Seeing in Three Dimensions" (2009). She was written about in a 2006 New Yorker article by Oliver Sacks.