The International Space Station (ISS) sprung a pressure leak on Wednesday night, possibly due to a collision with a micrometeorite.
The leak was first detected remotely by ISS flight controllers in Moscow and Houston, around 7 PM ET. The station crew was asleep at the time, and the ground controllers decided not to wake them as the puncture posed no immediate threat.
Once the crew was up, they tracked down the leak to a 1.5 millimeter hole located on the Russian side of the station, in the Soyuz capsule docked to the Rassvet module. The Soyuz is the space ferry that transports astronauts to and from Earth. The crew is still safe, according to NASA, and the hole has been patched until it can be fully repaired.
A micrometeorite is a tiny pebble of space debris, normally defined as any object that weighs less than a gram, or measures under two millimeters. Sourced from both artificial satellites and celestial bodies, millions of these particles swirl around low Earth orbits at speeds averaging six miles per second.
The ISS is constantly weathered by micrometeorites, and it’s not unusual for it to suffer a heavier hit that results in minor damage. In 2012, for instance, a micrometeorite dented the ISS cupola. Numerous leaks have been fixed by previous crews.
Like any vessel traversing inhospitable frontiers, the ISS is vulnerable to the threats of its environment. Fortunately, it has proven to be extremely resilient, and its inhabitants are well-prepared to respond to leaks and other hiccups.
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