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If there's any phrase an astronaut never wants to mutter, it's "Houston, we have a problem." Calling from the International Space Station on Thursday evening, Commander Chris Hadfield did just that. Well, he didn't actually quote that excellent Tom Hanks movie, but he did make a distressing call down to mission control. The astronauts on board the ISS had noticed what they believe to be ammonium cooling fluid leaking from the hull. The fluid is used to cool the power systems that control the space station's eight solar array panels, meaning that a total failure would cripple the floating habitat's ability to generate power.

But don't worry. Everything's going to be okay. NASA and Hadfield both say that the leak isn't putting the astronauts on the ISS in any immediate danger. The minor leak is actually not a new problem but an old headache that dates back to 2007. The ISS limped along for five years before astronauts fixed the problem on a space walk — or at least they thought they'd fixed it. Over the radio, Hadfield described the leak as "a very steady stream of flakes or bits" coming from the hull. (You can listen to the audio here.) "It is a serious situation, but between crew and experts on the ground, it appears to have been stabilized," Hadfield tweeted (from space!). "Tomorrow we find out for certain."

So chill out, Earth. Commander Hadfield really doesn't want you to worry about him. About an hour after the scary radio call and subsequent scary tweets, Hadfield offered this, "A view to put the mind at ease."

This article is from the archive of our partner The Wire.

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