While Suni Williams and Butch Wilmore’s situation is unusual, their return trip will be pretty routine, as they were already slated to fly home on a SpaceX capsule as part of a scheduled crew rotation.

Two NASA astronauts flew to the International Space Station in June on Boeing's Starliner capsule. The test flight was planned for eight days but technical troubles forced the capsule to return empty.

A spokesperson with NASA, which oversees SpaceX’s flights to the ISS, said “NASA and SpaceX are expeditiously working to safely return the agency’s SpaceX Crew-9 astronauts Suni Williams and Butch Wilmore as soon as practical, while also preparing for the launch of Crew-10 to complete a handover between expeditions.”