Air is leaking from the International Space Station (ISS) and no one knows why.
Two attempts to pinpoint the source of the leak in the past five weeks have failed to resolve the issue, though NASA says it poses no threat to the safety of the current three-person crew, or to the integrity of the ISS.
On both occasions, NASA and its Russian counterpart asked the crew — American Chris Cassidy, and Russians Ivan Vagner and Anatoly Ivanishin — to spend several days inside Russia’s attached Zvezda service module so that specialists on the ground could conduct pressurization tests throughout the rest of the orbiting outpost in the hope of discovering the location of the leak.
The latest effort took place last weekend, but in a briefing on Monday, September 28 regarding the upcoming Northrop Grumman NG-14 Cygnus cargo mission to the ISS, NASA official Greg Dorth confirmed that it was still trying to determine the cause of the problem.
“As of this morning, there was no clear indication of where the leak is,” Dorth said in comments reported by SpaceNews.
Dorth described the leak as “very, very small” and added that investigators are still poring over data from the most recent test in a search for clues.
Prior to their second isolation period in the Russian module, Cassidy revealed last week that in additional efforts to find the leak, he and Ivanishin had been checking the station’s window seals using an ultrasonic leak detector — but to no avail.
The NASA astronaut also repeated the point that the issue posed no risk to the crew, but added that it is “important to find the leak [so] we are not wasting valuable air.”
So far no luck finding the source, but it looks like we will try again with the module isolation this weekend. No harm or risk to us as the crew, but it is important to find the leak we are not wasting valuable air.
— Chris Cassidy (@Astro_SEAL) September 24, 2020
Investigators are keen to fix the issue during what is a relatively quiet period on the space station, with only three crew members currently on board. It’s about to get busy, though, with the coming weeks seeing several spacecraft arrivals that will increase the number of crew members to seven by early November. Cassidy, Ivanishin, and Vagner are set to depart the station on October 21.
