Thomas Marshburn

Sierra Space • Chief Astronaut and VP of Mission Integrity

Dr. Tom Marshburn serves as a Chief Astronaut and VP of Mission Integrity for Sierra Space, a leading commercial space company that is building an end-to-end business and technology platform in space to benefit life on Earth.

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 the Space Shuttle Medical Operations and the joint U.S./Russian Space Program, and as Medical Operations Lead for the International Space Station. Dr. Marshburn piloted the NASA SpaceX Crew-3 mission to the International Space Station, was a flight engineer on Expedition 66, and was Commander of Expedition 67. He spent 337 total days in space over his career and over 30 hours on spacewalks.

Dr. Marshburn is the recipient of 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.

Events

77th International Astronautical Congress (IAC 2026)

5 - 9 October 2026

Antalya, Türkiye

Participation:

International Astronautical Congress 2025

29 September - 3 October 2025

Sydney, Australia

Participation: