Tim Peake, the British astronaut, is going to do his first extra-vehicular activity – or spacewalk – next week.
He and his fellow astronaut Tim Kopra are going outside to repair a broken part of the station.
Peake said: "Our primary task will be to replace a failed solar shunt unit, which transfers electrical power generated by the solar panels."
It's a relatively straightforward job, according to ESA. The solar shunt is a box which can be removed by undoing a single bolt. The astronauts can replace it with a new one and take the broken one inside for repair. The ISS has been operating on seven solar shunts rather than the usual eight, since this one broke in November.
Once that's done, they will install cables for new docking ports.
Even though the main job isn't that complicated, it'll still take about six hours.
Just getting ready to go outside takes hours, too. The astronauts have to breathe pure oxygen for two hours before they go out, to avoid getting the bends.
So it'll be long, slow, and dangerous. But Tim's excited about it.
Tom Chivers is a science writer for BuzzFeed and is based in London.
Contact Tom Chivers at email@example.com.
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