On June 5, NASA moved its astronauts into a SpaceX CrewDragon as an emergency safe haven while Roscosmos pushed back a repair on a crack it has been sealing since 2019. Neither agency will confirm the fix on the record.
The International Space Station turned 27 this year. Last Friday morning, the two agencies that keep it running reached a public moment they have spent years avoiding: an open disagreement about whether the station is safe enough to stay in.
The disagreement surfaced after NASA moved its astronauts into a SpaceX Crew Dragon as an emergency safe-haven on June 5, 2026, while the Russian segment of the station leaked air around cracks that have been patched, by name, since 2019. Within hours, Roscosmos called off a planned repair walk. A week later, according to Ars Technica's reporting on background sources, the immediate problem has been fixed. Neither agency has confirmed that publicly.
That gap between what is being said behind the scenes and what is being said in front of cameras is the story. The ISS has a slow leak on the Russian side, and the two agencies that built it cannot publicly agree on how worried to be.
The cracks are in a small transfer tunnel, called the PrK, inside the Zvezda service module, the Russian-built backbone of the station's life support. Russian cosmonauts first flagged them in 2019 and have been chasing them with a sealant called Germetall-1 ever since. The work is delicate because the cracks open and close as the tunnel pressure cycles with each pass through Earth's shadow. A fix that holds in May can pull apart in June, which is why Roscosmos's early-2026 claim that the leaks had "stabilized" fell apart in May and worsened in early June.
The June 5 sequence was the closest the partnership has come to a public fracture over safety. Ars Technica reported that NASA directed its crew, including Crew-12 and Williams, to shelter in the docked Crew Dragon for roughly an hour while Russian cosmonauts worked the tunnel. That is the safe-haven posture crews train for, and the agency does not call for it casually. The same reporting, again on background rather than on the record, says Roscosmos then rescheduled a more durable structural repair that had been on its calendar, and that the immediate pressure problem is now resolved.
The silence is what makes this hard to read. Roscosmos has been opaque about the leak for years, including the early-2026 "stabilized" framing that did not survive contact with the May and June data. NASA, for its part, has declined to publicly characterize how serious its own concerns are. The result is a story that has to be told from background sources because the people who run the station will not tell it themselves, on a station that both agencies keep saying is fine.
The aging of the structure is no longer a side note. The first module launched in 1998, and the United States has committed to keeping the station flying until 2030, with a planned deorbit shortly after. There is no funded replacement. That makes the partnership more important, not less, and makes the silence harder to justify: the two agencies are running the second-oldest continuous human presence in orbit, with cracks they are sealing rather than fixing, and they are doing it without telling the people who pay for it how bad the sealant has to get before the walk is treated as a crisis rather than a maintenance call.
What to watch next is whether Roscosmos follows through on a real structural repair, not another Germetall-1 patch, and whether NASA says so out loud. Until then, the public version of the story is "leak held, crew fine, work continues." The version from background sources is closer to "we fixed it, but neither of us wants to put that in writing on a 27-year-old station we have agreed to retire before we have agreed to replace."