Dr. Tom Marshburn

Dr. Tom Marshburn is Chief Astronaut and Vice President, Mission Integrity of Sierra Space, a proven defense-tech space company delivering solutions for the nation's most critical space missions and advancing the future of security in space.

Based in Houston near NASA’s Johnson Space Center, the veteran NASA astronaut has been at Sierra Space for three years. He serves as a Clinical Assistant Professor of Aerospace Medicine at University of Texas Medical Branch.

Before joining Sierra Space, Dr. Marshburn served 28 years at NASA, where he was a veteran of three spaceflights, STS-127, Expedition 34/35, and Expedition 66/67 as part of Crew-3. Prior to his selection as an astronaut in 2004, Dr. Marshburn served as a Flight Surgeon for Space Shuttle Medical Operations and the joint U.S./Russian Space Program. He also served as Medical Operations Lead for the International Space Station and piloted the NASA SpaceX Crew-3 mission to the International Space Station. Marshburn was a flight engineer on Expeditions 34, 35 and 66. He spent 337 total days in space over his career and over 30 hours on spacewalks.

Dr. Marshburn is the recipient of the NASA Superior Achievement Award, the Space and Life Sciences Division Special Space Flight Achievement Award twice, and the Lyndon B. Johnson Space Center Superior Achievement Award.

He holds a Bachelor of Science in Physics from Davidson College, North Carolina, a Masters in Engineering Physics from the University of Virginia, a Doctorate of Medicine from Wake Forest University and a Masters in Medical Science from the University of Texas Medical Branch.

Tom is married to the former Ann M. Sanders, and they have one daughter.