NASA has ordered its astronauts to take shelter inside a docked SpaceX Crew Dragon spacecraft and prepare for possible evacuation from the International Space Station. But the crew resumed normal operations shortly after.
By Lee Billings edited by Clara Moskowitz

The Russian segment of the International Space Station is visible in this 2021 photograph. Chronic air leaks from a Russian module are a growing concern for the station’s safety and longevity.
NASA
Astronauts on the International Space Station (ISS) briefly sheltered and prepared for possible evacuation due to worsening air leaks from a Russian-built module, a NASA spokesperson said today.
The leaks are believed to come from microscopic cracks in a transfer tunnel called PrK, a small vestibule attached to the rear end of the Zvezda service module, which leads to a docking port for cargo spacecraft. Zvezda was the first all-Russian contribution to the ISS installed by the Russian space agency Roscosmos in July 2000. Engineers first noticed the leaks in 2019, but despite multiple efforts over the years to plug them and identify their underlying cause, they remained. a chronic problem. As the leaks continue, the orbital habitat is now losing about a pound of air per day.
“Following further leaks, Roscosmos chose to conduct a more thorough repair operation on Friday, June 5,” said NASA spokesperson Bethany Stevens. in a message on the social media platform [SpaceX] Dragon spaceship while repair is underway.
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In a statement released in Russian later today, Roscosmos officials wrote“The situation does not present any threat to the safety of the crew or the onboard systems; the pressure on board the ISS remains stable and is maintained at the nominal level,” according to an automatic translation.
Alongside Williams, at least three Crew-12 astronauts – Jessica Meir and Jack Hathaway of NASA and Sophie Adenot of the European Space Agency – sought refuge in a docked Crew Dragon spacecraft. Crew 12 also includes Roscosmos’ Andrey Fedyaev, but it was unclear whether he had taken shelter alongside his teammates as instructed. Fedyaev’s Russian colleagues, Sergei Kud-Sverchkov and Sergey Mikaev, remained outside the Dragon to deal with the situation.
Shortly after the astronauts entered the Dragon, officials at NASA’s Mission Control Center at the space agency’s Johnson Space Center transmitted a directive by radio so that they leave the “refuge configuration”, noting that “our Russian colleagues have chosen to only take measurements today”.
Stevens clarified his previous remarks in a follow-up statement on
Despite the shelter-in-place order, which may have resulted from miscommunication between NASA and Roscosmos mission controllers, the astronauts were likely in no imminent danger, says Jonathan McDowell, an astrophysicist and space situational awareness consultant. Air reserves on board could easily compensate for continued losses from leaks. Nevertheless, he said, the situation “is potentially extremely serious.”
“The problem is that a small crack could suddenly expand catastrophically,” he says. “It’s unlikely but not impossible, and it would risk losing the station and the crew.”
This alert highlights ongoing concerns about the security of the aging ISS, which has now been in orbit for more than a quarter of a century and far exceeds its expected lifespan. The PrK leak has become one of the most significant issues on the station, with NASA officially elevating the problem to its highest category of concern in internal safety assessments. Protocols are already in place to address leaks, with the hatch leading from Zvezda to PrK remaining closed unless access to Zvezda is necessary. When this hatch is opened, a corresponding hatch capping the US sections of the ISS is closed to limit any catastrophic decompression of the Russian segment.
NASA has announced plans to retire the ISS by the end of 2030, with deorbit planned shortly thereafter, but various efforts to ffurther extend the life of the space station are in progress.
Additional reporting by Meghan Bartels.
Editor’s Note (06/05/26): This is a breaking news story and will be updated.
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