Stranded Boeing astronauts to begin journey back to Earth from space station on Tuesday

Suni Williams and Butch Wilmore are returning after an unexpected extended stay on the International Space Station

Suni Williams and Butch Wilmore on board the ISS, where they have been since June 2024. AP

Two Boeing astronauts are set to depart the International Space Station on Tuesday after being stranded there since June due to technical issues with their Starliner spacecraft that delayed their return.

Suni Williams and Butch Wilmore are scheduled to undock from the station aboard a SpaceX Dragon capsule at 9.05am GST, along with two other astronauts, with a splashdown off the coast of Florida expected at 1.57am, Wednesday.

Their departure marks the end of a eight-day mission that stretched for months, now in the political spotlight as President Donald Trump ordered billionaire Elon Musk to bring them home, blaming Joe Biden for abandoning them.

"Mission managers will continue monitoring weather conditions in the area, as Dragon’s undocking depends on various factors, including spacecraft readiness, recovery team readiness, weather, sea states and other factors," Nasa said in a statement on Sunday.

Boeing Starliner astronauts arrive at International Space Station

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The Crew-9 return, which Ms Williams and Mr Wilmore became part of after their return was delayed, was also made possible after a replacement group, Crew-10, arrived on the station on Sunday.

Their return has become a focus for the new US administration, with Mr Trump and Mr Musk claiming to have offered Nasa an earlier opportunity to bring the astronauts back, which they said was declined by the Biden administration.

During a video press conference held with the astronauts on the ISS on March 6, Mr Wilmore said they had “heard some of these different things that have been said".

"I can tell you at the outset, all of us have the utmost respect for Mr Musk and obviously, respect and admiration for our President of the United States, Donald Trump. The words they've said, politics, I mean, that's part of life. We understand that. And there's an important reason why we have a political system and the political system that we do have, and we're behind it 100 per cent,” he said.

Lin Kayser, co-founder of LEAP 71 – a Dubai company that develops artificial intelligence models to generate rocket engines, told The National the politics was likely to deepen, with concerns that SpaceX is still the only reliable transport to the ISS, despite Nasa’s hopes to have several options.

“It’s already a political issue, especially with the change in the US administration and rhetoric from key players in the new government,” he said. “There are obviously concerns about Nasa relying solely on SpaceX to carry astronauts to space, which is likely to intensify political debate.”

Mr Musk is a “special employee” of the US government, leading the Department of Government Efficiency, with the remit of reducing federal spending. Nasa is also likely to be affected, with reports suggesting there could be a 50 per cent cut in the agency’s spending on science activities.

The future of the Starliner programme is also uncertain. Boeing has been developing the Starliner for nearly a decade as part of Nasa's Commercial Crew Programme, which the agency launched so that its astronauts had several "taxi" options.

But Starliner has faced various technical issues over the years, including on this first crewed test flight, in which the craft suffered helium leaks and thruster issues. Meanwhile, SpaceX has already launched nine crews for the agency.

“Starliner still has a role in the Commercial Crew Programme because Nasa values redundancy to ensure continuous access to the ISS,” said Mr Kayser. “However, continued delays are increasing costs for Boeing at a time when the company faces significant financial uncertainty. Boeing may ultimately be forced to reconsider Starliner’s long-term viability, despite its strategic value to Nasa. The uncertain future of the ISS adds another layer of risk, which could lead Boeing to cut its losses. Personally, I think they will end the programme.”

Dr Simeon Barber, senior research fellow at The Open University, told The National in an earlier interview it was “inevitable that a lot of further engineering work is needed on Starliner before [it is] considered a fully proven vehicle”.

"Perhaps the events since Starliner’s launch serve to vindicate Nasa’s decision to develop two independent options to get its astronauts to and from ISS,” he said.

Cost of progress

There is a lot of uncertainty surrounding the US space programme, including how potential budget cuts would affect Nasa and its partners. Mr Musk has called for an earlier retirement of the ISS, so focus can be redirected to launching crewed missions to Mars – a goal he has long campaigned for, especially during the recent US presidential election.

The Planetary Society, a US non-profit organisation, on Friday said the proposed 50 per cent budget cut in Nasa’s science activities would amount to an “extinction event” for space science and exploration.

“A cut of that magnitude would be disastrous for the US undermining its long-term credibility as a reliable partner in scientific missions,” said Mr Kayser. "Many current and future programmes depend on Nasa’s personnel and institutional expertise. I don’t think it will happen at that scale, though. But projects will face increased scrutiny, especially under the efficiency standards promoted by figures like Elon Musk.”

Mr Kayser said if Jared Isaacman, the billionaire who founded payment processing firm Shift4, was confirmed as the new Nasa administrator, he was unlikely to “pursue anything radical”.

“But right now, a lot remains uncertain," Mr Kayser added. "Private companies have little incentive to fund pure science missions, though there may be opportunities for Nasa to outsource certain aspects. In the current climate, it’s difficult to predict where this will lead."

Nasa will live broadcast the undocking and splashdown of the SpaceX capsule carrying Crew-9 on its website and social media channels.