Butch Wilmore and Suni Williams, who’ve been at the space station since June, will return to Earth along with two Crew-9 astronauts.

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.

NASA astronauts are returning to Earth after nine months in space. Experts have said a prolonged period in space can come with changes to human physiology and psychology.