For the 27th US-led spacewalk, ESA astronaut Alexander Gerst and NASA astronaut Reid Wiseman’s main job is to move an old cooling pump to its final position. The duo will then install a unit that will allow the Station’s robotic arm to remain powered even when it is being relocated.

This spacewalk is a tightly scheduled affair involving three astronauts and a large team on Earth in mission control. From the moment the astronauts enter open space the clock is ticking to get as much done as possible.

For this sortie, Alexander will be strapped to the Station’s robotic arm, which will be operated by NASA astronaut Butch Wilmore from inside. Reid has the callsign EV1 and will be wearing the suit with red stripes, while Alexander will be EV2 without stripes. During the point-of-view helmet camera shots, Reid’s camera has 17 in the bottom-right corner, while Alexander’s is number 20.

In addition to watching live, check for updates on this mission blog and follow on Twitter @esaoperations for behind-the-scenes information and explanations of what is happening.

Coverage of the spacewalk starts at 11:00 GMT (13:00 CEST)

A spacewalk is always tightly scheduled and the astronauts’ tasks can take more or less time than planned. Extra jobs are sometimes inserted into their timeline. Alexander’s outline schedule is as follows in GMT (CEST–2h):

  • 12:05 Exit the Station
  • 12:10 Orientation and equipment set up
  • 12:45 Move to robot arm and set up
  • 13:20 Ride arm to failed pump and retrieve it
  • 13:50 Ride arm to new location and fix pump to Station
  • 15:05 Ride arm to replace and return faulty light unit
  • 16:10 Stow robotic arm and clean up
  • 16:40 Install new power relay for robot arm
  • 17:40 Clean up and return to airlock
  • 18:10 Enter airlock to return inside Station