NASA Astronaut Suni Williams Retires After 27 Years, 608 Days in Space, and Record Spacewalking Hours

A record-breaking astronaut who ran the first marathon in space has retired from NASA after 27 years, leaving a legacy of pioneering human spaceflight. Suni Williams retired from NASA on Dec. 27, 2025, after 27 years of service. NASA Administrator Jared Isaacman stated, 'Suni Williams has been a trailblazer in human spaceflight...paving the way for commercial missions to low Earth orbit.'

Williams accumulated 608 total days in space, including 286 days on the 2024–2025 Starliner mission, which was extended due to spacecraft thruster issues. She conducted nine spacewalks (62h 6m total), a record for women and fourth-most overall.

Williams emphasized the role of the International Space Station, stating, 'The International Space Station...has made the next steps of exploration to the moon and Mars possible.'

The Starliner returned uncrewed in Sept. 2024; Williams and Butch Wilmore returned to Earth via SpaceX Crew-9 in March 2025. Williams holds a bachelor's in physical science and master's in engineering management, with 4,000+ flight hours in 40 aircraft.

Her career includes operational challenges during the Starliner mission extension, highlighting the complexities of commercial crew programs.