A seasoned NASA astronaut, who endured an prolonged nine-month stay in orbit due to spacecraft malfunctions, has concluded her illustrious 27-year tenure with the space agency, as officially announced on Tuesday.

Suni Williams concluded her service on December 27, with her recent, problematic mission marking her final extraterrestrial voyage.

In June 2024, Williams, alongside fellow astronaut Barry “Butch” Wilmore, embarked on an eight-day expedition intended to evaluate Boeing’s nascent Starliner capsule during its inaugural crewed flight. However, an unforeseen predicament resulted in their extended confinement in space.

Despite this challenging experience, Williams expressed on Tuesday that her time with NASA was “an unparalleled privilege.”

“Those acquainted with me understand that the cosmos is my most cherished domain,” she stated in a formal declaration.

Suni Williams and Butch Wilmore
Suni Williams (left) and Butch Wilmore (right) were originally slated for an eight-day mission. (NASA)

During Williams and Wilmore’s transit to the International Space Station (ISS), the new Starliner manufactured by Boeing encountered difficulties with its propulsion system, rendering it unsuitable for their return journey.

These technical setbacks compelled NASA to delegate the astronauts’ safe return to Elon Musk’s SpaceX, bypassing Boeing.

The two highly experienced astronauts finally made a secure return to Earth via SpaceX in March 2025. Wilmore subsequently announced his retirement in August of the same year.

NASA Administrator Jared Isaacman declared on Tuesday that Williams had been a “pioneer in human spaceflight,” further noting her significant role in shaping the “trajectory of exploration through her commanding presence aboard the space station” and her contribution to facilitating commercial missions to low Earth orbit.

Throughout her distinguished career, Williams accumulated a total of 608 days in space, positioning her second in cumulative time spent in orbit among NASA astronauts, according to agency records.

suni williams in 2018
NASA astronaut Suni Williams pictured at the Naval Ordnance Test Unit basin, Cape Canaveral Air Force Station, Florida, on March 28, 2018. (NASA/Kim Shiflett)

Her participation in the Starliner incident also places her sixth on the roster for the longest individual space missions undertaken by an American, as reported by NASA.

Williams has successfully executed nine extravehicular activities (EVAs), totaling 62 hours, which represents the most extensive spacewalk duration for a female astronaut and ranks fourth overall in cumulative spacewalk time.