NASA and SpaceX on Friday will count down to a long-awaited crewed rocket launch that will allow them to bring home U.S. astronauts Butch Wilmore and Suni Williams, who have been stuck on the International Space Station for nine months.

The flight was scrubbed on Wednesday night, and the astronauts will return to the launchpad for their trip to the International Space Station.

Tense, public squabbles between SpaceX CEO Elon Musk and NASA have stirred the space industry, but behind the scenes, space science has continued business as (almost) normal.