UK astronaut Tim Peake has run the distance of the London Marathon on a treadmill in the International Space Station (ISS).
To counteract the effects of weightlessness, he is using a harness to keep him on the running belt.
He ran the 42km (26.2mi) distance in about three hours, 35 minutes, the European Space Agency said.
Speaking before the event, Major Peake had called the marathon a "great challenge".
"I'm quite glad that this is happening later on in the mission so I've had plenty of time to get used to the T2 treadmill."
Elastic straps over the shoulders and round the waist keep Major Peake in contact with the running belt of the treadmill, located in the station's Tranquility Node.
The straps are designed to generate the foot force necessary to give astronauts' bones and muscles a workout in weightlessness.
He said: "One of the biggest challenges is the harness system. Obviously, my bodyweight has to be firmly attached to the treadmill by this harness, and that can rub on the shoulders and around the waist."
The Chichester-born astronaut ran the London Marathon in 1999, finishing in three hours, 18 minutes and 50 seconds.
He did not try to beat that time as his medical team wanted to ensure he was perfectly healthy for his return to Earth in June.
The ISS circles the Earth at a relative velocity of 28,800km/h (17,900mph), so Major Peake covered more than 86,000km (53,000mi) during his run.
Major Peake started at the same time as the other runners: 10:00 BST on 24 April.
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