Watch live as astronauts complete the 200th ISS spacewalk
After a short delay, the walk is underway


First American Spacewalk
After a nearly two hour delay, NASA’s 200th spacewalk on the ISS is currently underway.
Astronauts Peggy Whitson and Jack Fisher are replacing an ExPRESS Carrier Avionics, or ExPCA, box on the outside of the space station.
What is an avionics box? It supplies electricity and data connections to science experiments on @Space_Station: https://t.co/mzKW5uDsTi/ pic.twitter.com/9PKSHZ4BDL
— NASA (@NASA) May 12, 2017
You can watch the spacewalk live right here, listening in as the astronauts work and communicate with mission control:
A #spacewalk is more of a climb than a walk…but instead of rocks they're climbing on the outside of @Space_Station: https://t.co/mzKW5uV4hS/ pic.twitter.com/843jyt65QZ
— NASA (@NASA) May 12, 2017
This spacewalk got off to a late start, delayed by about two hours after a water leak was discovered in equipment that services the astronauts spacesuits while they are outside the space station. The spacewalk, which was originally scheduled to be 6.5 hours, is now abbreviated, and scheduled to last about 4 hours instead.
Astronauts typically go on spacewalks to install or repair equipment on spacecraft. Before the delay, the astronauts were also scheduled to install a protective shield on part of the ISS and a connecter in addition to replacing the Avionics box.