has retired from NASA after more than 22 years of service to the agency.
Thomas, who holds a doctorate in mechanical engineering, was selected to join NASA's astronaut corps in 1992. Before joining NASA, Thomas worked in private industry as a research scientist responsible for designing vehicle aerodynamics, flight controls and propulsion systems.
"Andy is an extraordinary researcher, engineer and astronaut who has done it all in his 22 years as a NASA astronaut," said Janet Kavandi, director of Flight Crew Operations at Johnson. "In his 177 days in space over four missions, Andy served as the payload commander for a dedicated research mission, lived aboard the Russian Mir space station, conducted a spacewalk during an International Space Station assembly mission and served a vital role as a crew member on our crucial Return to Flight mission, STS-114, following the tragic Columbia accident. Since his last flight, Andy has helped shape NASA's future through his tireless work supporting the development of future exploration technology. We will miss him deeply."
Thomas traveled to Mir in 1998 to assist in the transition to space station operations. He was the last American to live on Mir and performed numerous life and physical sciences experiments during the course of his stay. His research aboard Mir provided the framework for the multinational cooperation and collaborative research on today's International Space Station.
Thomas held multiple technical and leadership assignments during his NASA career, including deputy chief of the Astronaut Office.