Tim Peake practises using spacewalk rescue jet pack

Tim Peake is to carry out the first ever spacewalk by a British astronaut on 15 January to replace a failed voltage regulator outside the International Space Station (ISS).

Becoming detached is every astronaut's worst nightmare as the space station cannot move to rescue a free-floating crew member - he or she would have to try to get back using a type of jet pack.

Before Major Tim's launch, the Horizon programme filmed as he practised this using virtual reality.