ISS leak delays mission, raises concerns at NASA

NASA has delayed a mission due to a leak on the International Space Station as the aging space station approaches 30 years in orbit.

The aerospace agency has not provided much detail on the latest leak, but it could be a serious concern for the ISS, which is scheduled to be decommissioned in 2030.

This isn't the first time the ISS has sprung a leak. A slow but growing air leak in the transfer tunnel of the Russian service module has been present since 2019.

The Zvezda service model is one of the oldest on the ISS, launched in 1998. The transfer tunnel connects the Zvezda module with a docking port for supplies and Soyuz crew members.

Russian cosmonauts have made attempts to repair the small cracks but have only slowed the leaks, which lose about a couple of pounds of air each day. To manage the leaks, the hatch to the tunnel is kept closed except when a spacecraft docks.

Roscosmos said it had completely sealed the leak in the most recent round of repairs, and NASA also said the leak rate had halted.

However, the overall air pressure in the space station continued to drop, according to a report from Ars Technica.

What's leading to that air loss? That's an open question, though one possibility is that the seals on the hatch to the tunnel could be leaking, feeding the tunnel with air from the rest of the space station and creating a stable pressure that would make the leaks appear to be repaired.

NASA is monitoring the leak and has indefinitely delayed sending additional crew members to the ISS, pending the outcome of the issue.

One worst-case scenario is that the leak is a sign of what's called high-cycle fatigue, where metal hardens through use and eventually snaps. That kind of fatigue is what led to the crash of an Aloha Airlines flight in 1988 and has recently been suggested as the cause of the Titan submersible implosion.

If the leak is a result of high-cycle fatigue, it raises concerns that structures on the ISS could fail catastrophically.

NASA has said the crew currently on the ISS is safe and conducting normal operations.