Figure 3 from September 2024 Inspector General report, showing Zvezda’s location on ISS, as well as the station’s leak rate at that time.

According to a NASA update posted late yesterday, the agency had cause to order its astronauts to shelter in place within their Dragon capsule due to planned repair work proposed by the Russians.

The week of June 1, during Progress 95 spacecraft cargo operations, Roscosmos noted an increase of the previous leak rate to two pounds per day and identified new suspected leak areas in the PrK. Following this observation, Roscosmos made the decision to begin work toward a more extensive inspection and structural repair effort Friday morning. This revised approach involved cutting a bracket to better access an area identified as a possible leak source for further inspection, using a method that could have resulted in elevated risk to the structure in the area. In response, NASA directed the four SpaceX Crew-12 members and NASA astronaut Chris Williams, who flew to station aboard the Soyuz MS-28 spacecraft, to take a heightened safety posture, known as a safe haven, inside the SpaceX Dragon spacecraft during the procedure.

Later Friday morning, Roscosmos paused and did not perform the structural repair work in favor of conducting additional measurements and data assessments, which included inspection of suspected areas of interest and review of areas where sealant was previously applied. NASA strongly supported that decision, and as a result, following that decision, Crew-12 and Williams ended their safe haven activities and returned to normal operations aboard the orbiting laboratory.

In other words, the leak rate had increased to match the high rates seen from 2019 to 2025, and the Russians were planning work that threatened the structure of the module. It appears NASA objected, and eventually the Russians acceded to those objections.

What happens next however remains unclear. If the leak rate has suddenly jumped from one pound per day to two pounds a day, that suggests the situation is worsening, and doing so at an alarming rate. As this new leak occurred shortly after a Progress freighter docked at Zvezda, it suggested the docking instigated it. It also suggests any further dockings there are likely to worsen the situation even more.