Two astronauts stranded on the International Space Station since June and expected to return in February will have to wait at least another month in space.
NASA announced Tuesday that the launch for SpaceX's Crew-10 mission has been pushed to no earlier than late March.
One of the mission's objectives is to return Suni Williams and Butch Wilmore to Earth. They reached the space station on June 5 on Boeing's new Starliner crew capsule for a weeklong test, but were forced to stay when NASA determined a series of thruster failures and helium leaks in the Boeing capsule made it too risky for them to return.
Boeing flew its Starliner capsule home empty in September, and NASA moved Williams and Wilmore to a SpaceX flight that was scheduled for late February.
But NASA said in a blog post it and SpaceX, which is owned by billionaire Elon Musk, need time to complete processing on a new Dragon spacecraft for the mission. The new spacecraft is set to arrive at SpaceX's processing facility in Florida in early January.
"Fabrication, assembly, testing, and final integration of a new spacecraft is a painstaking endeavor that requires great attention to detail," Steve Stich, manager of NASA's Commercial Crew Program, said in the blog post. "We appreciate the hard work by the SpaceX team to expand the Dragon fleet in support of our missions and the flexibility of the station program and expedition crews as we work together to complete the new capsule's readiness for flight."
NASA said it and SpaceX assessed various options for managing the next crewed handover, including using another Dragon spacecraft.
"After careful consideration, the team determined that launching Crew-10 in late March, following completion of the new Dragon spacecraft, was the best option for meeting NASA's requirements and achieving space station objectives for 2025," NASA said in the blog post.
SpaceX's Crew 10 will be composed of NASA astronauts Anne McClain, the mission commander, and pilot Nichole Ayers; Takuya Onishi, a mission specialist with the Japan Aerospace Exploration Agency; and Russian cosmonaut and mission specialist Kirill Peskov.
Returning with Williams and Wilmore will be NASA astronaut Nick Hague and Russian cosmonaut Aleksandr Gorbunov.