NASA removed two astronauts from its Crew-9 mission to allow for Williams and Wilmore to join the cohort, and return onboard the SpaceX Dragon − which carries four people at a time. The altered Crew-9 − only Hague and Gorbunov − launched aboard the SpaceX Dragon Freedom in late September.

SpaceX's Falcon 9 rocket lifted off at 7:03 p.m. ET (2303 GMT) from NASA's Kennedy Space Center in Florida carrying four astronauts who will replace Wilmore and Williams, both of whom are veteran NASA astronauts and retired U.

SpaceX delivered a four-person crew to the International Space Station early Sunday, setting the stage for Barry Wilmore and Sunita Williams to depart.