NASA orders astronauts aboard the International Space Station (ISS) to shelter in docked spacecraft and prepare for a possible emergency evacuation after a worsening air leak was detected in the Russian segment of the orbital laboratory on Friday, 5 June 2026.
The four-member Crew-12 team—American astronauts Jessica Meir and Jack Hathaway, French astronaut Sophie Adenot of the European Space Agency, and Russian cosmonaut Andrey Fedyaev—were directed by NASA to don spacesuits and move into their SpaceX Crew Dragon spacecraft as a precaution while Russian crew members attempt to locate and repair the leak in the Zvezda service module’s transfer tunnel, known as PrK . The leak, which has grown in severity, prompted NASA to elevate the station’s safety posture to a “safe haven” status, a protocol last activated during a 2021 ammonia coolant leak scare.
Roscosmos cosmonauts are working under tight time constraints to isolate the source of the air loss, which has been traced to newly developed cracks in the PrK tunnel’s structure. NASA confirmed in a statement that previous mitigation efforts by Roscosmos had temporarily contained the issue, but the leak has now escalated beyond manageable levels . “We are coordinating closely with our Russian partners and international allies to resolve this situation permanently,” a NASA spokesperson said. The agency added that the Crew-12 astronauts remain in a heightened readiness state, with escape vehicles prepped for immediate undocking if conditions deteriorate.
The incident underscores the growing fragility of the ISS, now in its 26th year of continuous operation, where aging infrastructure increasingly demands urgent attention. While the station has weathered minor leaks before, this is the first time since the 2018 Soyuz pressure hole incident that a full evacuation protocol has been activated. Mission controllers in Houston and Moscow are monitoring pressure readings in real time, with no signs yet of a life-threatening situation.
If evacuation becomes necessary, the Crew Dragon would separate from the ISS and return to Earth within hours, carrying the four astronauts to a splashdown off the Florida coast. Backup plans include the use of a Russian Soyuz spacecraft, though its availability depends on the status of the leak and docking port accessibility. NASA has not yet set a deadline for a resolution but stressed that the crew’s safety remains the “absolute priority.”
The episode arrives amid heightened geopolitical tensions that have complicated ISS operations, with NASA and Roscosmos maintaining a fragile collaboration despite broader conflicts on Earth. The space station, a symbol of post-Cold War cooperation, now faces its most serious technical challenge in years—one that tests not only engineering resilience but also the endurance of international partnerships in orbit.