Butch Wilmore and Suni Williams docked on the space station in June (Picture: AFP)

Two astronauts who have been stuck on the International Space Station (ISS) for two months won’t be coming down anytime soon, Nasa said today.

Sunita Williams and Barry ‘Butch’ Wilmore were only meant to visit the orbital outpost for eight days as part of a test flight.

But their ride, Boeing’s Starliner, saw its propulsion system glitch out while docking, forcing Nasa to ask the pair to stay put while engineers conduct tests.

Nasa officials said today at an audio briefing that no return flight has been confirmed so far – but going home on the Starliner in an emergency is the plan B.

Ken Bowersox, the associate administrator at Nasa’s Space Operations Mission Directorate, said at an audio briefing that William and Wilmore are ‘well engaged’ on the ISS.

‘I know if I was in their position I’d be really happy to be there,’ he said. ‘I’d be happy to have the extra time.’

This photo provided by NASA shows Boeing's Starliner spacecraft which launched astronauts Butch Wilmore and Suni Williams to the International Space Station docked to the Harmony module's forward port on July 3, 2024, seen from a window on the SpaceX Dragon Endeavour spacecraft docked to the adjacent port. (NASA via AP)
Despite the hiccups, Boeing’s Starliner spacecraft docked at the Harmony module’s forward port on July 3 (Picture: AP)

They could be on board the ISS for another eight months, Bowersox said, as they’d have to wait to hitch a ride from a scheduled flight home from SpaceX, Elon Musk’s rocket company.

Other than that, the space agency isn’t entirely sure what to do. A decision was expected to be made in mid-August – now it’ll be the last week of the month.

‘This mission was a test flight,’ added Nasa’s chief astronaut, Joe Acaba. ‘They knew this mission might not be perfect.’

Asked if the Starliner would be used if an emergency happened on the ISS, Bowersox said: ‘We think the risk is reasonable to put Butch and Suni on that vehicle in a contingency.’

The space agency has a ‘lot of confidence’ in Starliner.

Exactly why five of the Starliner capsule’s 28 thrusters malfunctioned is unclear. Starliner’s computer rebooted them and managed to get four to fire, albeit, with diminished power.

Starliner also suffered five helium leaks – the inert gas is used to help power the thrusters in the near-weightless environment of orbit.

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