NASA’s SpaceX Crew 9 cannot return unless Crew 10 — its replacement — is launched into space. Here’s all you need to know about Sunita Williams’s space mission.

Suni Williams, the station's commander, had to tackle some overdue outdoor repair work alongside NASA's Nick Hague. Plans called for Williams to float back out next week with Butch Wilmore. Williams and Wilmore launched aboard Boeing’s new Starliner capsule last June on what should have been a weeklong test flight.