Billionaire Jared Isaacman, 41, exited first about 10:52 a.m. GMT, followed by SpaceX engineer Sarah Gillis, 30, becoming the first two non-government individuals to conduct such an excursion in space.

All their maneuvers were streamed live on the Space X website. The company is owned by billionaire, Elon Musk, who is also the owner of the Tesla electric car corporation.

The mission, which was named Polaris, appeared to successfully test trailblazing equipment, including slim spacesuits and a process to fully depressurize the Crew Dragon spacecraft cabin - technology that could be used in future private space missions.

It was one of the riskiest treks yet for Elon Musk's space company, the only private firm capable of routinely sending humans to and from Earth's orbit.

"Back at home we all have a lot of work to do, but from here, Earth sure looks like a perfect world," Isaacman said after emerging from the spacecraft, silhouetted with the half-lit planet glittering 700 km below him.

Isaacman, a pilot and the billionaire founder of electronic payments company Shift4 FOUR.N, is bankrolling the Polaris mission, as he did his Inspiration4 flight with SpaceX in 2021.

NASA administrator Bill Nelson praised the spacewalk. The agency helped fund Crew Dragon development beginning roughly a decade ago.

"Today’s success represents a giant leap forward for the commercial space industry and NASA's long-term goal to build a vibrant U.S. space economy," Nelson wrote on the X platform.