NASA has said a 'serious medical condition' affecting an astronaut aboard the International Space Station could prompt an early return of the current four-person crew.
The situation arose on 7 January 2026, when NASA announced it had postponed a planned spacewalk scheduled for 8 January due to what it described as a “medical concern” involving a member of the Space Station's Crew-11.
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NASA hasn't disclosed the astronaut’s identity, nor the specific nature of the concern, citing medical privacy protocols.
However, while NASA initially had said it would return all four Crew 11 astronauts, in an update, officials said the affected crew member was in "stable condition" and being monitored closely on the ISS.
That means the space agency may opt to cancel the early return of the crew.
"We are actively evaluating all options, including the possibility of an earlier end to Crew-11’s mission," NASA said.
About Crew 11
Crew-11, which launched to the International Space Station aboard a SpaceX Crew Dragon spacecraft on 1 August 2025, includes NASA astronauts Zena Cardman and Michael Fincke, Japanese astronaut Kimiya Yui from the Japan Aerospace Exploration Agency, and cosmonaut Oleg Platonov of Roscosmos, the Russian space agency.
The mission was originally planned to last approximately six months, with a return to Earth planned for February 2026.
According to NASA officials, the medical concern arose on Wednesday afternoon while the crew was aboard the ISS.
In response, the agency indefinitely postponed the crew's extravehicular activity (EVA), or spacewalk.
In a press conference on Thursday 8 January 2026, NASA Administrator Jared Isaacman told reporters the agency had decided to bring back the crew early, but it appears the affected astronaut's "stable" condition now means NASA is reviewing the situation.
Few details were given regarding the nature of the medical situation, but NASA did say it wasn't an injury and was not related to space operations.
However, if NASA does go ahead with the early return of Crew 11, it will mark the first early evacuation in the history of the Space Station, which has been continuously inhabited since 2000.
Dr James Polk, NASA's Chief Health and Medical Officer, said at the news conference that this is the first time in the history of the space agency that a crewed mission would return to Earth early as a result of a medical issue.
