A SpaceX capsule has arrived at the International Space Station to take home stranded astronauts Butch Wilmore and Suni Williams.
The pair have been stuck on the ISS after the Boeing Starliner capsule they arrived on in June was deemed unfit to return them to Earth.
The Starliner capsule suffered thruster failures and helium leaks, with Nasa deciding it wasn't safe for the astronauts to return on it. It was sent back to Earth empty earlier this month.
Nasa astronaut Nick Hague and Russian cosmonaut Aleksandr Gorbunov boarded the ISS shortly after the SpaceX Crew Dragon capsule docked at the station on Sunday.
Wilmore and Williams, who were the first crew to fly on the troubled Starliner, are now due to return home with Hague and Gorbunov on Crew Dragon in February next year.
The pair were only supposed to be in space for eight days before technical failures meant they could not return home. If they return in February, they will have been in space for eight months.
Boeing, the company behind the Starliner capsule, had insisted it was safe for the astronauts to use to return home.
But Nasa decided against it, instead using the SpaceX vessel for the mission.
The astronauts have previously spoken about the difficulties of being stranded in space for longer than planned.
Speaking at a press conference from the ISS earlier this month, Mr Wilmore said: “It’s been quite an evolution over the last three months, we’ve been involved from the beginning through all the processes of assessing our spacecraft, Calypso.
“And it was trying at times. There were some tough times all the way through.
“You certainly, as the commander and the PLT (pilot) of your spacecraft, you don’t want to see it go off without you, but that’s where we wound up.”
Ms Williams added: “I miss my two dogs, I miss my friends.
“But you know what? Like Butch said, there are so many people on Earth that are sending us messages.
“And it makes you feel just right at home with everybody when we’re able to have those conversations with our friends and family at home.”
The Starliner capsule had already been delayed for several years because of setbacks during its development.
Nasa retired its own space shuttle fleet in 2011, meaning it has to rely on either Russia’s Soyuz craft to get to and from the ISS or on private companies.
In 2020, Elon Musk’s SpaceX became the first private company to take astronauts to the ISS.
