SpaceX may bring astronauts home in 2025 if Boeing remains unfit

US' National Aeronautics and Space Administration (Nasa) is working with Elon Musk's SpaceX on plans to return two astronauts to Earth in the event that they're unable to travel on the troubled Boeing craft that initially carried them to space.

Nasa representatives announced the contingency plan Wednesday, saying astronauts Barry "Butch" Wilmore and Sunita "Suni" Williams could come back to Earth around February 2025 with a two-person crew on SpaceX's Crew-9 mission. That mission is slated to launch to the International Space Station in September.

The agency said it needs to make a final decision in mid-August on whether to return the astronauts home on the Boeing spacecraft. The call may ultimately be made by NASA's Associate Administrator Jim Free or Bill Nelson, the agency's top official.

Wilmore and Williams have been living on the International Space Station since June 6, after launching on the inaugural crewed flight of Boeing's CST-100 Starliner spacecraft.

The mission is a critical test to determine if the vehicle is safe to regularly carry astronauts to and from orbit. Originally, the two astronauts were supposed to stay on the station for roughly a week, but have now been in orbit for two months. If Nasa decided to go the SpaceX route, Starliner would come home empty prior to Crew9's launch.