With bilateral relations being at their worst since the 1980s and the station’s planned death in sight, persistent air leaks onboard are steadily escalating tensions between NASA and Roscosmos. The American space agency aired its concerns in public during an ISS Advisory Committee last week. The International Space Station’s survival in low Earth orbit hinges on collaboration between the United States and Russia despite being long-standing geopolitical rivals.
The NASA meeting was scheduled to be an hour long but only lasted ten minutes with the air leaks being the primary topic. Air has been leaking out of the PrK transfer tunnel between the Zvezda module and a Russian docking port since September 2019, according to Ars Technica. The leak significantly worsened over this year. It measured 2.4 pounds of air lost per day, then increased to 3.7 pounds per day by April.
Time for a quick ISS geography lesson. The station began in 1998 with the mating of NASA’s Unity module and Roscosmos’ Zarya in orbit. The ISS sprawled out in both directions with two distinct halves, one American and one Russian. The American side features NASA, European and Japanese modules while all the modules on the Russian side are Roscomos equipment.
The Zvezda module, launched in 2000, was the third module of the ISS. Engineers on both sides agree that air is leaking out of cracks in the vestibule between the Zvezda and the PrK tunnel. The disagreement is why it’s happening. Roscosmos simply believes it’s due to fatigue from micro-vibrations and NASA posits that more significant pressure and mechanical stresses are the cause.
The disagreement between NASA and Roscosmos also extends to the potential consequence of the problem. Bob Cabana, retired astronaut and NASA’s ISS Advisory Committee chair, didn’t hold back in his concern during the meeting. According to SpaceNews, Cabana said:
“While the Russian team continues to search for and seal the leaks, it does not believe catastrophic disintegration of the PrK is realistic,” he said. “NASA has expressed concerns about the structural integrity of the PrK and the possibility of a catastrophic failure.”
“The Russians believe that continued operations are safe but they can’t prove to our satisfaction that they are, and the U.S. believes that it’s not safe but we can’t prove to the Russians’ satisfaction that that’s the case,” he concluded.
Cabana isn’t alone in his concern. Crew-8 astronaut Michael Barratt added that NASA closes the hatch between the American and Russian sides when the PrK is open. The only definitive solution proposed would be sealing off the PrK permanently, eliminating one of Russia’s four docking ports. However, NASA’s precaution is an admittance that it believes the Zvezda module could get opened like a can and take the rest of the ISS with it, but everything is seemingly fine for Roscosmos.