Video report by ITV News Science Correspondent Alok Jha
Major Tim Peake has told ITV News what surprises him most about life in space, as he held his first press conference since reaching the International Space Station.
Speaking to Science Correspondent Alok Jha, Major Peake said the "blackness of space" was the thing that surprised him most.
"We always talk about seeing the view of planet earth and how beautiful it is so you come to expect that.
"What people don't mention that much is when you look the opposite direction and you see how dark space is - I mean it's the blackest black and you see how small the Earth is in that blackness. That was a real surprise to me."
Major Peake delighted the journalists assembled to speak to him during the press conference by performing a zero-gravity somersault as the camera rolled.
He also said he would be working on Christmas Day, but would call his friends and family from space.
"And what a wonderfully unique place to call people from on Christmas Day. It's going to be absolutely fantastic to be able to call friends and family from up here - and also, of course, to have some time to take some pictures of our beautiful planet."
Since landing on Tuesday evening, the astronaut has been tweeting about his experience as part of the European Space Agency's Principia mission - even revealing that his first meal on board was a bacon sandwich.
He said his first 48 hours had been "busy but incredible", adding: "Amazing how fast the body adapts to new environment. Found my tea...life is good!"
He also took the time to thank the Queen for her message of support, telling her he was "honoured" she saw him blastoff into space.
Much of Britain, including the Prime Minister, took time out of work to watch Major Peake's journey into space from Kazakhstan on Tuesday.
After a six-hour journey to the space station via the tiny Soyuz capsule, he and fellow crew members Yuri Malenchenko and Tim Kopra were forced to endure a tense docking situation when the auto-pilot malfunctioned.
Following the safe landing Major Peake sent his first tweet, hailing Malenchenko, his commander, for an "outstanding job" in steering the arrival manually.
Major Peake will be on board the ISS for six months, and is carrying out a number of experiments while he is up there, as well as undergoing a gruelling exercise regime to maintain his strength and fitness.
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