Four astronauts are set to launch to the International Space Station (ISS) on Wednesday (March 12), marking the beginning of the end for NASA astronauts Suni Williams and Butch Wilmore's extended stay in space. Originally planned for a week-long mission, Williams and Wilmore have spent nine months aboard the ISS due to issues with Boeing's Starliner capsule.

The Starliner, which carried them to the ISS, faced several malfunctions, including thruster problems and leaking propulsion, prompting NASA to return the capsule to Earth unmanned. Consequently, NASA rearranged crew rotations to secure seats for Williams and Wilmore on a SpaceX Dragon capsule for their return journey. The Dragon capsule arrived at the ISS on September 29, carrying NASA astronaut Nick Hague and Roscosmos cosmonaut Aleksandr Gorbunov, who will accompany Williams and Wilmore back to Earth at the end of their mission.

The new crew, consisting of NASA astronauts Anne McClain and Nichole Ayers, Japanese astronaut Takuya Onishi, and Russian cosmonaut Kirill Peskov, will launch aboard a SpaceX Falcon 9 rocket on a mission known as Crew-10. Their liftoff is scheduled for 7:48 p.m. ET from NASA’s Kennedy Space Center in Florida, with docking at the ISS expected by Thursday (March 13) at 6 a.m. ET. This new crew will take over from the current team, allowing Williams and Wilmore to finally return home.

NASA and SpaceX have maintained that the timing of Williams and Wilmore’s return is based on safety considerations. Although there have been claims from SpaceX CEO Elon Musk and President Donald Trump that the return was delayed for political reasons, NASA insists the decision was made to ensure the safety of the crew and the space station.

An exact date for Williams and Wilmore's return has not been announced, as NASA and SpaceX are monitoring conditions at the splashdown sites off Florida. The handover period at the ISS typically lasts several days, during which outgoing crew members train and brief their replacements on ongoing experiments and work.

Boeing's Starliner program continues to face challenges, with plans for its next mission still uncertain. The Starliner experienced several issues during its Crew Flight Test, but NASA and Boeing are working to address these before the capsule's next operational mission, tentatively planned for August 2025.

Simon Conway