The spacewalkers switched their spacesuits to battery power at 7:12 a.m. EDT to begin the spacewalk, which is expected to last between six and seven hours.
Watch the spacewalk on NASA TV and on the agency’s website.
Behnken is extravehicular crew member 1 (EV 1), wearing the spacesuit with red stripes, and using helmet camera #20. Cassidy is extravehicular crew member 2 (EV 2), wearing the spacesuit with no stripes and helmet camera #18.
The spacewalkers will be working on several tasks to upgrade systems and prepare for future station upgrades. Behnken and Cassidy will remove handling aids from two locations at the base of station solar arrays, prepare the outside of the Tranquility module for the arrival later this year of the Nanoracks commercial airlock, route ethernet cables, and remove a lens filter cover from an external camera.
This is the 231st spacewalk in support of space station assembly and maintenance. It is the 10th spacewalk for both astronauts.