As the six-person Station slept last week, a pressure/atmosphere leak appeared in the Soyuz MS-09 crew vehicle attached to the Station. The leak occurred when a very small breach (only 2 millimeters) opened up in the Soyuz Orbital Module’s hull, allowing a very small amount of atmosphere/pressure to leak into space. The leak was so small that NASA and Roscosmos did not wake the crew when the leak first appeared.
The Russians quickly devised temporary and more permanent fixes for the leak – both of which were implemented. The crew is in no danger, and there appears to be no issues with Soyuz MS-09’s continued life at the Station and ability to return its three crewmembers safely to Earth in December. The main drama relates to the root cause of the hole.