An American billionaire has become the first person to take part in a private spacewalk – against the spectacular backdrop of the Earth.
A spacewalk is considered one of the most dangerous activities an astronaut can do in orbit.
SpaceX Polaris Dawn spacewalk – live updates
It was delayed by around four hours earlier this morning – with no explanation given – before final safety checks of the spacesuits and equipment were carried out and SpaceX officials confirmed the mission was “go for a spacewalk”.
First images broadcast from inside the Dragon capsule showed the four-strong crew preparing for the historic event – and sharing fist bumps with each other.
Billionaire Jared Isaacman, 41, was the first to exit the capsule – joining a small, elite group of spacewalkers who until today had included only professional astronauts.
After opening the hatch, a body camera showed his ascent through the narrow opening before incredible footage showed the spacewalk taking place to huge cheers from mission control at Cape Canaveral in Florida.
“It’s gorgeous,” he said, in awe of what he could see, as he eased out of the spacecraft into the vacuum of space, hundreds of miles from Earth.
He kept a hand or foot attached to the capsule the whole time as he flexed his arms and legs to see how the new spacesuit held up.
“The handsfree demonstration is very comparable to the trainer, in terms of the foot restraint,” he added, as he tested his spacesuit.
He had said before lift-off earlier this week: “Whatever risk is associated with it, it is worth it.”
“I wasn’t alive when humans walked on the moon,” he said.
“I’d certainly like my kids to see humans walking on the moon and Mars, and venturing out and exploring our solar system.”
The tech entrepreneur blasted into space from Florida before dawn on board a SpaceX Falcon 9 rocket on Tuesday for the five-day flight – along with mission pilot Scott Poteet, 50, a retired US Air Force lieutenant colonel, and SpaceX employees Sarah Gillis, 30, and Anna Menon, 38, both senior engineers at the company.
Ms Gillis followed Mr Isaacman out of the capsule on Thursday to carry out the same mobility tests.
They each had 12ft (3.6m) tethers but did not unfurl them, and instead bobbed up and down in weightlessness, no higher than their knees out of the capsule.
The mission, called Polaris Dawn, to test a new line of spacesuits is the Elon Musk-led company’s riskiest mission yet – from a space capsule that doesn’t have a safety airlock, and in suits far slimmer than the bulky protective layers worn by NASA astronauts.
It is the first of three funded by Mr Isaacman – a pilot and the founder of electronic payment company Shift4.
He has refused to say how much he is paying for the missions, but they are believed to have cost hundreds of millions of dollars based on Crew Dragon’s roughly $55m (£42m) per-seat price for other flights.
Ms Gillis could be heard saying “pretty good” as she carried out her spacewalk – before she followed Mr Isaacman back into the capsule, after being told what sounded like she had less than six minutes of oxygen supply left.
“Pressure indicates good seal,” mission control told the astronauts, reassuringly, as the hatch was shut again.
“That was really cool,” said one of the presenters on the SpaceX live stream.
Mr Menon and Mr Poteet remained inside the spacecraft during the spacewalk.
Polaris Dawn was planned down to the minute with little room for error. The crew spent two-and-a-half years training with SpaceX mission simulations.
There were a few glitches, however – Mr Isaacman had to manually pull the hatch open instead of pushing a button on board, and Ms Gillis reported seeing bulges in the hatch seal.
Only government astronauts with several years of training have done spacewalks in the past.
There have been around 270 on the International Space Station (ISS) since it was set up in 2000, and 16 by Chinese astronauts on Beijing’s Tiangong space station.