NASA once again delays Sunita Williams' return to Earth from space; what is the reason this time?

Sunita Williams aboard the ISS (Image: NASA)

Two US astronauts, stranded on the International Space Station (ISS) since June, will remain there until at least late March 2025. NASA confirmed the delay on Tuesday.

Butch Wilmore and Sunita Williams arrived at the ISS in June. They were aboard Boeing's Starliner capsule for what was to be a short eight-day mission. However, issues with the spacecraft’s propulsion system forced a change of plans.

NASA later decided to bring the Starliner back uncrewed. Wilmore and Williams were then planned to return in February 2025 on a SpaceX mission. But new delays mean they will stay in space for at least nine months.

Smooth Crew Transition for Ongoing Projects

NASA’s SpaceX Crew-10 mission, originally scheduled for February, now targets March 2025. The mission will bring four astronauts to replace the current crew. NASA said the change allows more time to prepare the spacecraft.

The new Dragon spacecraft will be ready by January 2025. Its fabrication and testing require careful planning and attention to detail, according to Steve Stich, NASA’s Commercial Crew Program manager.

"We appreciate SpaceX's hard work in supporting our missions," said Stich. “The flexibility of the station crew also plays a key role.”

Wilmore and Williams were originally part of Starliner’s crewed test flight. Their mission was to demonstrate the spacecraft’s readiness before Boeing could fly astronauts on regular missions. The issues with the thrusters halted that plan.

Starliner returned uncrewed in September, and NASA revised its mission. Crew-9’s astronauts, including Wilmore and Williams, will stay until Crew-10 arrives. This overlapping crew ensures a smoother transition, as astronauts exchange details about ongoing projects.

SpaceX has been regularly flying astronauts to the ISS since 2020. Boeing’s Starliner will eventually join the fleet, despite current technical problems. Both spacecraft are expected to serve NASA’s future missions, including those to the Moon and Mars.

(Inputs from agencies)