Williams and Wilmore both arrived at the ISS last June, aboard the first crewed test flight of Boeing's Starliner spacecraft. The astronauts were only slated for a 10-day mission, but issues with Starliner during docking led to multiple delays in their return, with NASA ultimately deciding to have Starliner make the journey back to Earth uncrewed.

During their walk, the pair removed some communication equipment and swabbed parts of the outside of the space station to check for microbes.