NASA crew to make rare early return after medical issue in space

Four astronauts will return from the International Space Station more than a month ahead of schedule after an unnamed crew member experienced a medical issue.

NASA did not provide details on the nature of the problem, citing privacy concerns. The agency generally does not discuss details of health issues related to astronauts.

The affected crew member is in stable condition, NASA previously confirmed, and is not expected to receive any special treatment during the return trip, said Dr. James Polk, NASA’s chief health and medical officer at agency headquarters. The astronaut would also be better served if assessed on the ground, Polk added.

“We have a very robust set of medical equipment on board the International Space Station,” Polk noted during a press conference Thursday. “But we don’t have all the equipment I would need in the emergency department, for example, to perform an exam on a patient.

“And in this particular incident,” he added, “we would like to finish this work, and the best way to finish this work is on the ground.”

The returning group, which includes American astronauts Mike Fincke and Zena Cardman, Japan Aerospace Exploration Agency astronaut Kimiya Yui and Roscosmos cosmonaut Oleg Platonov, makes up NASA’s SpaceX Crew-11. The mission, part of the orbiting laboratory’s regular staff rotation, is expected to end next month at the earliest. Typically, NASA wouldn’t bring a team like this back to Earth until another one was in place.

New NASA administrator Jared Isaacman — who flew into orbit twice on private SpaceX missions — said he made the call to bring the group of four astronauts home.

Isaacman said at a news conference Thursday that his decision was driven by the fact that four crew members are expected to launch to the space station on NASA’s Crew-12 mission in the coming weeks, and that the agency is evaluating ways to speed up that launch. The mission was scheduled to start around mid-February.

The Crew-11 team will leave the space station in “a few days,” Isaacman said.

Spacewalk delayed

NASA revealed the astronaut’s medical concerns Wednesday when it announced that the agency was choosing to postpone a spacewalk, citing undisclosed “medical concerns.”

“These are the situations for which NASA and our partners train and prepare to execute safely,” NASA noted in a statement.

When the Crew-11 astronauts return, only one NASA astronaut will remain aboard the football-field-sized orbiting laboratory: Chris Williams, who arrived at the space station in late November aboard a Russian Soyuz capsule as part of a ride-sharing agreement between the United States and Russia.

Officials said Thursday that Williams is well prepared to handle any tasks given to him and they are confident he will soon be joined by the Crew 12 astronauts to bring staffing levels back to normal levels.

“That’s one of the reasons we carry mixed crews on Soyuz and American vehicles – because we want to make sure we have operators for both (American and Russian) segments” of the space station, said Amit Kshatriya, NASA associate administrator.

Dr. Farhan Asrar, a space medicine researcher and associate dean at the Toronto Metropolitan University Faculty of Medicine, told CNN via email that health care providers face unique challenges when trying to treat or diagnose astronauts as they orbit more than 200 miles above Earth. These limitations can turn even common ailments – like toothache or ear pain – into difficult medical conundrums.

“Even though astronauts undergo frequent and ongoing health checks, the extreme environment of space places significant strain on health (stress on the heart, bones, eyes, kidneys, mood and other systems),” Asrar said.

A history of space medicine

NASA’s decision not to release the affected astronaut’s name and details about his condition follows a long-established pattern. Information about the impact of spaceflight on the human body or other medical problems that arise during missions is usually made public as part of broader scientific studies and research, and specific astronauts are usually not identified.

Conditions such as space adaptation syndrome – a condition characterized by vomiting and dizziness experienced by many astronauts during their first hours in microgravity – only came to light after years of research and revelations in academic journals. This condition, however, is common and has affected astronauts since the beginning of spaceflight.

An incident in which an astronaut suffered a case of jugular vein thrombosis, a dangerous condition in which a blood clot can form in a person’s jugular vein, was also revealed in an academic journal. The identity of the impacted astronaut has never been made public.

Additionally, after SpaceX’s Crew-8 missions returned from the space station in October 2024, one of the four crew members experienced a “medical issue” and was airlifted to a hospital in Florida.

The space agency did not provide further details at the time, saying only in a statement that the crew member was “in stable condition” and “under observation as a precaution.” The identity of the crew member is still unknown.

Over the past 25 years of space station operation, NASA has worked to respond to a “multitude” of medical issues, Polk noted during Thursday’s briefing.

“Luckily for us, we had equipment and medications and other things to be able to handle all of that, so we were able to complete the treatment and/or diagnosis in orbit,” Polk said.

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