ISS Astronauts Ordered to Evacuate as Space Station Air Leak Worsens

ISS Astronauts Ordered to Evacuate as Space Station Air Leak Worsens

In one of the most alarming moments in recent space history, NASA ordered all four Crew-12 astronauts aboard the International Space Station to suit up, take shelter inside their SpaceX Crew Dragon spacecraft, and prepare for a potential emergency evacuation on Friday, June 5, 2026 — all because of a rapidly worsening air leak in the Russian section of the station.

The good news: a few hours later, the crew was given the all-clear to return to normal operations. But the incident has put the world on notice — the ISS has a serious, growing problem that isn't going away.

What Happened on June 5, 2026?

At 9:04 a.m. ET on Friday morning, NASA mission control at Johnson Space Center gave the order. All four members of the Crew-12 mission were told to don their spacesuits, move into their docked SpaceX Crew Dragon spacecraft, and assume what NASA called an "elevated safety posture" — the agency's term for being ready to undock and return to Earth at a moment's notice.

The trigger was a worsening air leak inside the Zvezda service module transfer tunnel — a passageway on the Russian side of the ISS known by its Russian acronym, PrK. Russia's space agency, Roscosmos, had begun a more intensive repair operation that morning, and NASA didn't want its astronauts anywhere near the affected section while the work was underway.

"Out of an abundance of caution, NASA has directed all four of the agency's SpaceX Crew-12 members to assume an elevated safety posture in the Dragon spacecraft while the repair is underway," NASA spokesperson Bethany Stevens said in an official statement. "We continue to work with our Russian counterparts to arrive at a more permanent resolution."

Less than two hours after the shelter order, Roscosmos paused the repair work to collect new measurements and data. With the immediate risk reduced, NASA instructed the crew to exit the safe haven configuration and return to regular operations aboard the ISS.

Who Was on Board? Meet the Crew-12 Astronauts

The four astronauts ordered to shelter were:

• Jessica Meir — NASA astronaut, veteran of a previous ISS long-duration mission and famous for conducting the first all-female spacewalk in 2019
• Jack Hathaway — NASA astronaut, on his first long-duration spaceflight
• Sophie Adenot — European Space Agency (ESA) astronaut representing France, on her first spaceflight
• Andrey Fedyaev — Russian cosmonaut from Roscosmos, serving as the crew's liaison to the Russian segment

All four were reported safe throughout the incident.

What Is the Zvezda Module — and Why Is It Leaking?

The Zvezda service module is one of the oldest and most critical parts of the ISS. Launched into orbit in July 2000 aboard a Russian Proton rocket, Zvezda was the third module to join the station and serves as the command center for the Russian segment. It provides crew quarters, life support, an aft docking port, and two additional ports for research and airlock modules.

The PrK transfer tunnel — the section at the heart of today's crisis — connects Zvezda to the station's aft docking port, where Soyuz crew ships and Progress resupply craft dock. It's more than 25 years old, and its aging aluminum structure has been showing the strain.

The first signs of a leak appeared back in September 2019. Since then, Russian cosmonauts have attempted multiple patch jobs using tape, glue, epoxy, and sealants — and while those efforts slowed the leaks, they never fully solved the problem. Over the last few months, Roscosmos and NASA have been locked in ongoing discussions about the cause and the best path forward.

Then, on Monday, June 2, the situation escalated sharply: the leak rate doubled — jumping from roughly one pound of air per day to two pounds per day, according to a senior NASA official. That spike prompted Roscosmos to escalate from routine patching to a full-scale structural repair operation, which in turn triggered Friday's emergency shelter order.

Why This Matters: The Bigger Picture

This is not just a one-day story. The ISS has been continuously staffed since November 2000 — over 25 years — and is currently funded through 2030, after which it is planned for a controlled deorbit. But incidents like today's are a reminder that the station is aging, and the Russian segment in particular is showing signs of serious wear.

The Zvezda leak has already caused major disruptions. Earlier in 2026, NASA indefinitely delayed the Axiom Mission 4 private astronaut launch specifically because of the escalating PrK leak investigation. The private crew — which included Indian Air Force pilot Shubhanshu Shukla, set to become the first Indian astronaut to visit the ISS — was left waiting on the ground while engineers assessed the situation.

The station's aging has also been at the center of diplomatic friction between NASA and Roscosmos. The two agencies have debated for months over the root cause of the cracks and who bears responsibility for the permanent fix.

Timeline of the ISS Air Leak Crisis

• September 2019 — First air leak detected in the Zvezda PrK transfer tunnel
• 2020–2021 — Multiple patching attempts by Russian cosmonauts; leak slows but never stops
• 2025 — New pressure signatures detected; Axiom-4 launch delayed due to ISS leak concerns
• June 2, 2026 — Leak rate doubles from 1 to 2 pounds of air per day
• June 5, 2026, 9:04 a.m. ET — NASA orders Crew-12 to suit up and shelter in Crew Dragon
• June 5, 2026, ~11:00 a.m. ET — Roscosmos pauses repair work; NASA gives crew all-clear to return to normal operations

Is the ISS Safe to Keep Flying?

The short answer: for now, yes. NASA and Roscosmos have consistently maintained that the leak poses no immediate threat to the crew, as the station can be repressurized using nitrogen tanks delivered by cargo spacecraft. The agency has also confirmed that the station's structural integrity remains intact.

But the long answer is more complicated. At two pounds of air lost per day, the station requires increasingly frequent repressurization. The aging Zvezda module is becoming harder to maintain. And with retirement planned for 2030, NASA has to weigh the cost of major structural repairs against the remaining lifespan of the station.

Today's incident was resolved without evacuation. But it was a stark reminder of just how close the margin can get — 250 miles above Earth, with four astronauts in spacesuits waiting to see if they'd have to leave.

Key Takeaways

• NASA ordered Crew-12 astronauts to shelter in their SpaceX Crew Dragon on June 5, 2026, amid a worsening air leak in the ISS Zvezda module
• The four crew members — Jessica Meir, Jack Hathaway, Sophie Adenot, and Andrey Fedyaev — were all safe
• The leak rate in the PrK transfer tunnel doubled earlier this week, from 1 to 2 pounds of air per day
• Roscosmos paused repairs to take new measurements; NASA gave the all-clear about 2 hours after the initial shelter order
• This air leak has been ongoing since 2019 and has already delayed private astronaut missions to the ISS
• The ISS remains operational but this incident highlights the growing risks of flying a 25+ year old space station