NASA astronaut Suni Williams retires from the agency on December 27, 2025, capping a 27-year career marked by groundbreaking missions, record-setting spacewalks, and leadership aboard the International Space Station (ISS).
Williams completed three space station missions, logging 608 days in orbit, the second-most cumulative time in space by a NASA astronaut.
She conducted nine spacewalks totaling 62 hours and 6 minutes, the longest spacewalk time by a woman and fourth-longest overall. Williams also became the first person to run a marathon in space.
“Suni Williams has been a trailblazer in human spaceflight, shaping the future of exploration and paving the way for commercial missions to low Earth orbit,” said NASA Administrator Jared Isaacman.
“Her work advancing science and technology laid the foundation for Artemis missions to the Moon and progress toward Mars. Her extraordinary achievements will continue to inspire generations.”
Career highlights
Williams made her first flight aboard space shuttle Discovery (STS-116) in December 2006, followed by STS-117 aboard Atlantis, serving as a flight engineer for Expeditions 14/15. During this mission, she completed four spacewalks, setting a then-record for a single expedition.
In 2012, Williams launched from Baikonur Cosmodrome in Kazakhstan for a 127-day Expedition 32/33 mission, serving as station commander for Expedition 33. She performed three spacewalks, repairing a station radiator and replacing a component linked to the station’s solar power system.
Williams’ final mission came in 2024–2025 aboard the Boeing Starliner and SpaceX Crew-9, joining Expeditions 71/72 and commanding the station during Expedition 72. She completed two additional spacewalks on that mission.
“Suni is incredibly sharp, and an all-around great friend and colleague,” said Scott Tingle, chief of the Astronaut Office.
“She’s inspired many of us, and we’re all going to miss her greatly.”
Beyond spaceflight
Williams also contributed to NASA’s operational and training programs. She served as deputy chief of the Astronaut Office, director of Operations in Star City, Russia, and helped establish helicopter training platforms for future Moon missions. In 2002, she participated in NEEMO missions, living for nine days underwater to simulate extreme space environments.
A retired U.S. Navy captain, Williams is an accomplished helicopter and fixed-wing pilot, logging more than 4,000 flight hours across 40 aircraft types. She holds a bachelor’s in physical science from the U.S. Naval Academy and a master’s in engineering management from Florida Institute of Technology.
“Space is my absolute favorite place to be,” Williams said.
“It’s been an incredible honor to serve in the Astronaut Office and fly in space three times. The ISS, the people, and the science have made the next steps to the Moon and Mars possible. I can’t wait to watch NASA make history.”
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