Tim Peake Prepares For Historic Spacewalk
Tim Peake will become the first Briton to
walk in space later when he ventures outside the International Space
Station (ISS) to fix a broken power unit.
The spacewalk - known as Extra-Vehicular Activity (EVA) -
will last almost six-and-a-half hours and is scheduled to begin at
12.55pm UK time.
Major Peake will carry out the mission with NASA colleague Colonel Tim Kopra, who will be taking part in his third spacewalk.
The pair will work in 45-minute blocks of daylight, then complete darkness, as the ISS orbits Earth every 90 minutes.
The European Space Agency (ESA) said every detail of the spacewalk has been "choreographed minutely".
Video:
A Look At Tim Peake's Spacesuit
Major Peake will start breathing pure oxygen two hours prior
to the mission, because the pressure inside their suits is lower than
that of the ISS.
The astronauts will enter an airlock before opening its hatch and venturing outside.
They will remain tethered to Space Station supports,
although their suits will have built-in jet packs that can be used if
they accidentally drift away.
Colonel Kopra will lead, heading to the solar units that need to be repaired.
Video:
Spacewalks: How They Work
Major Peake will follow with the replacement equipment once he is given the green light.
The repairs should be completed in under three hours, and then ground control will perform checks.
In the second half of the spacewalk, the pair will lay
cables for new docking ports and reinstall a valve that was removed last
year.
If they are ahead of schedule, the astronauts will be given
"bonus tasks", including laying another cable and cutting some
unnecessary power caps.
Video:
Peake To Perform Spacewalk
The spacewalk will be tiring for the pair as they fight against the pressurised suits.
NASA astronaut Leroy Chiao, who carried out six spacewalks, told Sky News: "It's very physically demanding.
"You're working inside a pressure suit. Every time you move
your arm or even your fingers it takes a bit of energy so you quickly
build up a workload.
"You are really working against that pressure, you've got
limited visibility, but you've practiced lots so you know how to move
and you know how to get around."
Video:
Tim Peake Messages The Queen
Sunrises can also be "blinding for moments" from space,
according to the ESA, and the pair will need to check on each other
frequently and make sure their suits have not sustained any damage.
Once they get back, their ISS colleagues will help with a 25-minute clean-up and further checks.
Then they will be able to take off their suits and adjust to the pressure back in the station.
Soon after arriving at the ISS in December Tim Peake said he was hoping to be assigned a spacewalk.
Video:
The Story Of Tim Peake In Space
"I watched a sunset and a sunrise at different times. Looking out of the space station is incredible," he said.
"To think you might be out there on a spacewalk when that happens is going to be the most incredible sensation ever."
