Astronauts aboard the International Space Station (ISS) were placed on a temporary evacuation alert on Friday after a worsening air leak was detected in the Russian segment of the orbiting laboratory. As a precaution, NASA directed the crew to shelter inside their docked spacecraft and prepare for a possible emergency evacuation if conditions deteriorated.

The alert remained in place for around two hours before being lifted, after joint assessments by NASA and Russia’s space agency, Roscosmos, confirmed that repair efforts had stabilised the situation. Normal operations aboard the station were subsequently resumed.

Leak Found in Russian Module

According to Roscosmos, two leak points were identified in the transition chamber of the Zvezda service module. One of the leaks has already been sealed, while work continues on addressing the second.

The agency stated that pressure levels inside the station remain stable and within safe limits, indicating that the situation is currently under control.

International Space Station has faced recurring air leakage concerns in this module over the past several years, prompting repeated monitoring and repair efforts by both NASA and Roscosmos.

Crew Briefly Sheltered in Spacecraft

As a precaution during the alert, the four-member Crew-12 team along with an additional astronaut were instructed to enter the docked SpaceX Crew Dragon capsule and wear spacesuits in case an emergency evacuation was required.

The Crew-12 mission includes NASA astronauts Jessica Meir and Jack Hathaway, European Space Agency astronaut Sophie Adenot, and Roscosmos cosmonaut Andrey Fedyaev. NASA confirmed that the crew remained safe throughout the incident.

Recurring Technical Concern

The leak issue has been traced to the PrK transfer tunnel attached to the Zvezda module, where small cracks have been observed multiple times in recent years. Despite repeated repairs by international teams, the issue has persisted.

Reports indicate that the rate of air loss recently increased, prompting heightened safety protocols and the latest precautionary shelter order.

NASA officials have previously acknowledged that the cracks remain a closely monitored engineering concern, requiring continuous assessment to ensure crew safety.

Return to Normal Operations

After joint review by mission controllers, NASA and Roscosmos confirmed that the station’s atmosphere remained stable and there was no immediate threat to astronauts onboard. The evacuation alert was lifted, and the crew resumed their scheduled scientific and maintenance activities.