ESA astronaut Tim Peake and NASA astronaut Tim Kopra will exit the International Space Station next week to repair a power unit on the outside.
The two Tims arrived at the Space Station on 15 December but this will be their second involvement in a spacewalk: Tim Peake assisted Tim Kopra and Station commander Scott Kelly when they moved an equipment carrier on 21 December.
Inside the Station, Scott Kelly will help the spacewalkers into and out of their suits – a major operation in itself.
Before the astronauts leave they will breathe pure oxygen for two hours to purge their bodies of nitrogen. The spacesuit pressure is lower than in the Space Station and the drop could give them the ‘bends’, much like scuba divers rising too quickly to the sea surface.
Donning their spacesuits and safety equipment will take hours before they enter the airlock to reduce the pressure until it is safe to open the exterior hatch.
Tim Peake comments, “I am thrilled at this opportunity for a spacewalk. Right now we are focusing on preparing the tools, equipment and procedures. “Maintaining the International Space Station from the outside requires intense operations – not just from the crew, but also from our ground support teams who are striving to make this spacewalk as safe and efficient as possible.”
The Station has eight shunt units to regulate power but has been operating with only seven since last November.
Tim concludes, “If the spacewalk is successful, this will restore the International Space Station to 100% of its operational capability.”