NASA astronaut Suni Williams has retired after 27 years of service, marked by record-breaking time in space and leadership on the International Space Station. Her career included three missions, nine spacewalks, and contributions to future exploration efforts. The retirement took effect on December 27, 2025.
Suni Williams, a trailblazing NASA astronaut from Needham, Massachusetts, ended her 27-year tenure with the agency on December 27, 2025. Over her career, she accumulated 608 days in orbit, ranking second among NASA astronauts for total time off Earth. This included tying for the sixth-longest single spaceflight by an American, at 286 days alongside astronaut Butch Wilmore during missions involving Boeing's Starliner and SpaceX's Crew-9.
Williams' first spaceflight launched in December 2006 aboard the space shuttle Discovery for STS-116. As flight engineer for Expeditions 14 and 15, she conducted four spacewalks, setting a record at the time, and returned via STS-117 on Atlantis. Her second mission in 2012, a 127-day stint from Kazakhstan's Baikonur Cosmodrome, saw her command Expedition 33 on the International Space Station. There, she performed three spacewalks to fix a radiator leak and replace a power-transfer component.
Her final mission began in June 2024 with Wilmore on Boeing's Starliner Crew Flight Test, leading into Expeditions 71 and 72, where she commanded the station once more. She added two spacewalks and returned in March 2025 on SpaceX Crew-9. Overall, her nine spacewalks totaled 62 hours and 6 minutes, the most for any woman and fourth all-time. Williams also became the first to complete a marathon in space.
Beyond flights, she participated in the 2002 NEEMO underwater mission, served as deputy chief of the Astronaut Office, directed operations in Star City, Russia, and developed helicopter training for lunar preparations. A retired U.S. Navy captain with over 4,000 flight hours, she holds degrees from the United States Naval Academy and Florida Institute of Technology.
NASA leaders praised her impact. Administrator Jared Isaacman called her a "trailblazer" whose work supports Artemis missions to the Moon and Mars. Johnson Space Center Director Vanessa Wyche highlighted her pioneering leadership. Astronaut Office Chief Scott Tingle described her as an inspiring colleague. Williams herself reflected, "Space is my absolute favorite place to be," expressing excitement for NASA's future.