U.S. space officials don’t like to talk about the dangers of astronauts flying on the aging International Space Station, whose components are now more than a quarter-century aged.
However, a modern report confirms that NASA managers responsible for operating the space station are seriously concerned about the petite Russian part of the station, a tunnel connecting the larger module to the leaky docking port.
Russian and U.S. officials know that this petite PrK module, which sits between the Progress spacecraft’s airlock Star module, has been leaking since September 2019. New reportreleased Thursday by NASA’s inspector general, includes details not previously published by the space agency that underscore the seriousness of the problem.
Novel details about the leak
For example, in February this year, NASA found the leak rate had increased from less than 1 pound of atmosphere per day to 2.4 pounds per day, and in April the rate increased to 3.7 pounds per day. Despite years of investigation, neither Russian nor U.S. officials have identified the cause of the leak.
“While the root cause of the leak remains unknown, both agencies focused on internal and external welds,” said the report, signed by Deputy Inspector General George A. Scott.
The risk mitigation plan is to leave the hatch on Star the module leading to the PrK tunnel closed. Ultimately, if the leak continues to worsen, the hatch may need to be closed permanently, reducing the number of Russian docking ports on the space station from four to three.
NASA has sought to publicly minimize concerns about the cracking problem, as so far it remains confined to the PrK tunnel and has not spread to other parts of the station. Nevertheless, – Ars reported in June that the issue of rupture had reached the highest level of concern in the space agency’s 5×5 “risk matrix,” used to classify the likelihood and consequences of threats to spaceflight activities. Russian leaks are currently rated “5” for both high probability and sedate consequences.
At the time, NASA did not comment or confirm the space agency’s concerns about the risk matrix assessment. However, the modern report confirms the agency’s concerns.
“In May and June 2024, ISS Program and Roscosmos officials met to discuss increased concerns regarding increased levels of leaks,” the inspector general report states. “The ISS program subsequently raised the risk of a service module transfer tunnel leak to the highest level in its risk management system. According to NASA, Roscosmos is confident that it will be able to monitor and close the service module hatch before the leak rate reaches an unsustainable level, however, NASA and Roscosmos have not reached an agreement on the point at which the leak rate is unsustainable.”
An uncertain future in low Earth orbit
The report comes as NASA considers the future of the space station. The U.S. space agency and Russia have struck a deal to continue flying the station through 2028, and NASA would like to extend operations through 2030. NASA anticipated it would agree to this extension more than a year ago, but no agreement has been finalized yet.
When the station reaches its end of life, NASA intends to shift its low-Earth orbit activities to private space stations and has funded initial development work by Axiom Space, Northrop Grumman, Blue Origin and Voyager Space. Northrop has since withdrawn from the competition, recognizing that it would not be a profitable business. There is general uncertainty as to whether any private space station operators will be ready in 2030.
Another potential option for NASA is to extend the life of the space station beyond 2030, but that would require a lot of work to ensure the space station structure remains viable, as well as another extension agreement with Russia. The United States’ partnership with this nation has been severely strained by Russia’s invasion of Ukraine.
“Extending the ISS through 2030 will require significant funding to operate and maintain the station, accept increased risks from its components and aging structures, and ensure continued support from NASA’s international partners,” the modern report says. “The matter is further complicated by the likelihood that NASA will continue to face challenges related to a flat or reduced budget, inflation and supply chain.”
This story originally appeared on Ars Technica.