NASA is cutting short the Crew-11 mission aboard the International Space Station due to a crewmember’s medical issue, and canceling the first spacewalk of the year that was originally planned for Thursday.

“I have come to the decision that it’s in the best interest of our astronauts to return Crew-11 ahead of their planned departure,” NASA administrator Jared Isaacman said Thursday in a press conference, adding that their return would take place “in the coming days.”

The space agency released no further details on the name of the crewmember or of the medical situation, but reiterated that the astronaut is now fully stable.

Dr. James Polk, NASA’s chief health and medical officer, said, “It’s not an emergency evacuation, but we are erring on the side of caution for the crew member.”

The spacewalk was to be performed by American astronauts Mike Fincke and Zena Cardman, who would exit the orbiting lab for almost 7 hours and “finish preparing a power channel where a new solar array is set to be installed on the ISS,” according to Live Science. It would have been Cardman’s first spacewalk, and Fincke’s ninth.

The other two astronauts were Japan’s Kimiya Yui and Russia’s Oleg Platonov.

The American-Japanese-Russian crew first arrived on the ISS in August 2025 and was scheduled for at least a sixth-month stay. The group was then supposed to be replaced with Crew-12 in mid-February, but this is now up in the air due to the early departure. Isaacman said they may “potentially pull [the crew] forward.”

“It is unclear what returning Crew-11 home early would mean for the ISS, as such changes to the usual rotation are highly unusual,” Live Science reported.

There are also three other astronauts currently living on the space station who launched from a Russian Soyuz spacecraft in November and are due back to Earth in the summer.

NASA announced it will provide further details regarding the upcoming crew in the next 48 hours.