Spacecraft's Air Leak Persists Despite Recent Attempted Repairs on the International Space Station
The International Space Station (ISS) continues to face an ongoing air leak in its Russian segment, specifically in the interstitial chamber of the Zvezda module. Despite recent repair attempts, the leak rate has been reduced but remains unabated[1][2][3].
The leak was first detected in 2019, and over the years, it has progressively worsened. The rate doubled over six years from about 0.45 kg to more than 0.9 kg of air per day[2]. NASA has designated the leak as a critical risk[2].
Roscosmos and NASA are collaborating to locate and permanently fix the leak, but the exact source and definitive remedy have not yet been agreed upon[1][2]. There is consideration of potentially hermetically sealing off the affected module if the situation deteriorates further, which would reduce docking nodes for cargo but allow the ISS to continue operations[2].
Recent repair efforts, including sealing operations in June 2025, have shown some promise. The pressure in the ISS appeared stable after a repair attempt, suggesting that the repair may have worked[5]. However, a space agency insider has expressed little confidence in the current state of the repairs[6].
The cracks and leaks in the ISS are a "top safety risk" according to the 2024 Office of Inspector General report into NASA's Management of Risks to Sustaining ISS Operations through 2030[7]. NASA and Roscosmos have not reached an agreement on the point at which the leak rate is untenable[8].
In addition, the Crew-11 mission, a joint venture between SpaceX and NASA, was stood down on July 31 due to cloud cover at the launch site[9]. The Axiom 4 mission, scheduled for August 1, was also postponed to allow engineers to understand a new pressure signature after a recent repair effort in the aft-most segment of the ISS's Zvezda service module[4].
ESA astronaut Andreas Mogensen has suggested that one option for dealing with the leaks is to seal off the affected section of the ISS[10]. NASA has made the announcement about the postponement of the Axiom 4 mission in June[9]. A NASA report [PDF] states that the leaks are in the Service Module Transfer Tunnel[8].
Scientists from Russia and the US are working to track down the root cause of the leak and prevent its occurrence in future space stations[1][2][4]. The ongoing situation has highlighted the importance of drawing lessons to prevent similar issues on future space stations[1][2][4].
[1] https://www.nasa.gov/feature/nasa-and-roscosmos-work-to-find-and-repair-leak-in-russian-segment-of-iss [2] https://www.space.com/russian-space-station-leak-iss-repair-attempts.html [3] https://www.bbc.com/news/science-environment-57693249 [4] https://www.nasa.gov/feature/nasa-announces-postponement-of-axiom-4-mission [5] https://www.space.com/iss-air-leak-repair-attempt-may-have-worked.html [6] https://www.space.com/iss-air-leak-repair-efforts-dont-inspire-confidence-space-agency-insider.html [7] https://oig.nasa.gov/sites/default/files/audit-reports/2024-036_management_of_risks_to_sustaining_iss_operations_through_2030.pdf [8] https://www.npr.org/2021/06/22/1010891395/nasa-and-roscosmos-struggle-to-find-and-repair-air-leak-in-iss [9] https://www.space.com/nasa-spacex-crew-11-mission-delayed.html [10] https://www.space.com/iss-air-leak-could-be-fixed-by-sealing-off-affected-section-esa-astronaut-says.html
- Evidently, scientists from the fields of science, both US and Russian, are collaborating to identify the root cause of the air leak in the ISS and prevent similar issues in future space stations.
- With the ongoing air leak in the health-and-wellness of the ISS astronauts, there has been a surge in the importance of cloud-basedair quality monitoring systems to ensure a safe environment for the crew.
- The use of artificial intelligence and machine learning algorithms could potentially assist in the tracking and maintenance of space and astronomy facilities like the ISS, ensuring the stability and longevity of these structures.
