Astronaut Tim Peake ran the London Marathon from space

British astronaut Tim Peake ran a marathon in solidarity with runners in London on Sunday - just 250 miles above them.

He took part in the challenge with the help of a special space-proof treadmill, and used a harness system to actually stay in place on it, tracking his progress through London's streets with the help of an iPad.

If a marathon wasn't already a gruelling enough physical challenge, turns out in space it's even harder. Sustained exposure to microgravity wastes astronauts' muscles and thins their bones - which makes keeping fit and healthy really difficult.

Tim finished the 26-mile race with an estimated time of 3:35:21, according to the European Space Agency. He's run the London Marathon once before, in 1999, with an impressive time of 3:18:50, and was aiming for a new time of under four hours.

As part of his six-month stay aboard the International Space Station Tim has been conducting experiments which will hopefully help researchers on earth better understand the effects of muscle wastage and osteoporosis.

Well done Tim!

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