The future of two Nasa astronauts stuck on board the International Space Station (ISS) due to issues with Boeing’s new Starliner capsule remains uncertain.
A final decision on when and how Barry Wilmore and Sunita Williams will return to Earth will not be made until the end of next week at the earliest, if not the following week, US space agency Nasa said.
Two options for the return journey of the two US astronauts – who have been on the ISS since June although they were only supposed to stay one week – are currently being discussed, Nasa said.
The first option involves the pair returning on the Starliner, though the spacecraft would need to be fixed first after it experienced engine problems and suffered a helium leak upon arrival.
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The other option is to fly the Starliner back to Earth without a crew, though this would require extensive software reconfiguration. Two of the four astronauts due to travel to the ISS on the SpaceX Crew 9 mission in September would then need to be bumped to allow Wilmore and Williams to return to Earth with that crew when their mission ends in February.
“Butch and Suni are doing well on the International Space Station, where they continue to complete important tasks alongside the Expedition 71 crew,” Nasa boss Bill Nelson said on X following a press briefing. “Safety is our core value, and Nasa is evaluating every option to ensure Butch and Suni’s safe return.”
The Starliner is a partially reusable spacecraft that consists of a capsule around 3 metres high for the crew and a service module. Unlike the Crew Dragon vehicle of Elon Musk’s company SpaceX, it does not land on water but on dry land.
After years of delays, the spacecraft set off on its first manned test flight from the Cape Canaveral space centre in Florida at the beginning of June.
The plan is for the Starliner to become an alternative to SpaceX’s Crew Dragon space capsule to transport astronauts to the ISS.