Nasa continues to puzzle over ISS air leaks

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There were only two hours between Nasa issuing an evacuation order to astronauts on the International Space Station and giving the all clear on Friday afternoon. But scientists remain puzzled over the cause of the small air leaks that prompted Nasa to tell astronauts to shelter in their docked spacecraft and put on spacesuits. The leaks were first noticed on Russia’s Zvezda service module in 2019, but last week the amount of air they were releasing increased from one pound of air a day to two. This was enough for Nasa to ask the four crew of the ISS to prepare for evacuation “out of an abundance of caution”. Although air supplies currently compensate for the loss from the leaks, the concern is that a small crack could widen enough to pose an imminent danger to those on board. The ISS has been continuously occupied for more than 25 years, well beyond its intended design life, and is due to be retired by 2031.