SpaceX published live webcam footage on Thursday showing two of the four-person Polaris Dawn crew undertaking the first-ever spacewalk completed by non-astronauts.

"The first spacewalk from dragon has begun!" they wrote on social media site X, referencing the name of the Dragon Crew capsule.

Daredevil billionaire Jared Isaacman was the first to step out of the capsule, and was followed by SpaceX engineer Sarah Gillis.

"Back at home, we all have a lot of work to do. But from here, it sure looks like a perfect world," Isaacman said as he looked at Earth from outside the capsule.

Musk eyes Mars

The trip marked Isaacman's second journey into space, an undertaking so expensive he had to foot part of the bill for the company's improved spacesuits. The entrepreneur and his three fellow crew members, which included a second SpaceX engineer and a US Air Force pilot, underwent extensive training before the journey.

The mission initially flew further out into space than even the International Space Station (ISS) to reach a distance of 870 miles (1,400 km) from Earth. This marked the furthest distance crewed space flight has gone in decades.

They then dropped to about half that altitude in order to carry out the spacewalk, something that is usually considered the most dangerous part of an astronaut's job.

SpaceX CEO Elon Musk has said that the Polaris Dawn mission is part of his larger plan to bring settlers to the surface of Mars.

es/kb (AP, AFP)