'You can't afford a slip in concentration'
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Tim Peake rehearses for spacewalk in a huge swimming pool

Tim Peake is to carry out the first ever spacewalk by an "official" British astronaut, alongside Nasa astronaut Tim Kopra, on 15 January to replace a failed voltage regulator on the International Space Station.

While Major Peake has said he is keen to do a spacewalk, he admits it is one of the three high-risk activities that astronauts under take.

The BBC Horizon programme filmed his spacewalk rehearsal - which involved at least four hours deploying cables in a giant swimming pool.

  • 14 Jan 2016
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