Key events
Richard Luscombe
The astronauts’ extended stay on the ISS became an opportunity for some political mischief, with Elon Musk, the SpaceX founder and Donald Trump acolyte, insisting without evidence they were “abandoned” in space by the Biden administration.
Trump, in turn, has attempted to paint last week’s long-scheduled routine crew rotation flight, carrying replacements for Williams and Wilmore, as a special rescue mission ordered by the White House.
Wilmore told reporters from space earlier this month that he believed Musk’s claim that Joe Biden rebuffed an offer to bring them home last year was “absolutely factual”, while also admitting: “We have no information on … what was offered, what was not offered, who it was offered to, how that process went.”
Yet in February he told CNN: “We don’t feel abandoned, we don’t feel stuck, we don’t feel stranded. I understand why others may think that … if you’ll help us change the rhetoric, help us change the narrative, let’s change it to ‘prepared and committed’, that’s what we prefer.”
Musk subsequently became embroiled in a public dispute with the Danish astronaut and space station veteran Andreas Mogensen, who accused him of lying, and pointed out that Tuesday’s return of Williams and Wilmore, alongside their ISS Crew 9 colleagues was scheduled as long ago as September.
In response, Musk posted to the X platform he owns that Mogensen was “fully retarded”, drawing him deeper into conflict with retired astronauts and ISS veterans and brothers Scott and Mark Kelly, who defended their European colleague.
The bad blood has continued, with Musk calling Mark Kelly, Democratic senator for Arizona, “a traitor” for visiting Ukraine and urging US military and humanitarian support for the country in its war against Russia; and the politician retorting that Musk was “not a serious guy”.
The two US astronauts stuck on the ISS were meant to return home onboard a Boeing Starliner – but Nasa decided to move them on to a SpaceX-crewed flight instead due to “too much uncertainty” about the Starliner, which had problems after the capsule sprang small leaks and some of its thrusters failed.
Williams and Wilmore, two veteran astronauts, arrived at the ISS on 6 June as part of a crucial test by Starliner before it could receive Nasa approval for routine flights. However, their planned eight-day mission turned into a months-long stay after technical issues emerged, including reaction control thrusters that failed during Starliner’s first docking attempt.
Four of the spacecraft’s five failed thrusters later reactivated in orbit, the Associated Press reported, adding that the thrusters are crucial for the spacecraft to back away from the ISS after undocking and for maintaining the capsule in proper position for the deorbit.
On 2 August, Boeing said in a blog post that it had conducted “extensive testing of its propulsion system in space and on the ground”.
The embattled manufacturer, which has struggled to compete with SpaceX and has taken in $1.6bn in losses on the Starliner program, added: “The testing has confirmed 27 of 28 RCS [reaction control system] thrusters are healthy and back to full operational capability. Starliner’s propulsion system also maintains redundancy and the helium levels remain stable.”
Describing the decision to bring the Starliner back uncrewed in September, Steve Stich, program manager for Nasa’s commercial crew program, said: “The bottom line relative to bringing Starliner back is … there was just too much uncertainty in the prediction of the thrusters … it was just too much risk with the crew.”
When Williams, Wilmore, Hague and Gorbunov left the ISS, they were replaced by a new crew, who arrived to emotional scenes on Sunday.
A SpaceX capsule delivered four astronauts in a Nasa crew-swap mission that will allow Williams and Wilmore to return home after nine months on the orbiting lab. Williams said it was a wonderful day and “great to see our friends arrive”, speaking shortly after her colleges emerged on to the orbital lab.
In a live video, Nasa astronaut and team commander Anne McClain said: “Hi everybody down there on Earth. Crew 10 has had a great journey up here, about 28 hours to get back up to the space station. And I cannot tell you the immense joy of our crew when we looked out the window and saw the space station for the first time.”
She said: “You can hardly even put it into words … orbiting the Earth for the last couple of days, it has been absolutely incredible.”
McClain’s team were welcomed by the station’s seven-member crew, which included Wilmore and Williams – veteran astronauts and retired Navy test pilots who have remained on the station after problems with Boeing’s Starliner capsule forced Nasa to bring it back empty.
Nasa astronauts expected to splash down just before 6pm Florida time
Hello and welcome to our live coverage of two US astronauts – stuck for more than nine months on the International Space Station – returning to Earth today.
Nasa said it expects the astronauts to splash down off the Florida coast at approximately 5.57pm ET Tuesday (21.57 GMT). Favourable weather meant their expected re-entry was moved forward from Wednesday.
Barry “Butch” Wilmore and Sunita Williams are heading home with another American astronaut and a Russian cosmonaut aboard a SpaceX Crew Dragon craft, which arrived at the ISS early on Sunday.
The stranded duo have been on the ISS since June, after the Boeing Starliner spacecraft they were testing on its maiden crewed voyage suffered propulsion issues and was deemed unfit to fly them back to Earth.
On Sunday, Nasa said: “The updated return target continues to allow the space station crew members time to complete handover duties while providing operational flexibility ahead of less favorable weather conditions expected for later in the week.”
Nasa astronaut Nick Hague and Roscosmos cosmonaut Aleksandr Gorbunov are also returning on the Dragon capsule, which undocked from the space station at 1.05am ET on Monday.
The final stages of their journey will be broadcast live on the new Nasa+ streaming service. And we will have a live feed at the top of this live blog.