Scientific American

The world’s first commercial space walk, performed by billionaire Jared Isaacman and SpaceX engineer Sarah Gillis, tested new technology and was practically flawless

It wasn’t a small step—more a clamber, really—but as billionaire entrepreneur Jared Isaacman climbed partway out of a SpaceX Dragon capsule located nearly 740 kilometers above Earth on early Thursday morning, he made a giant leap into spaceflight history.

That’s because Isaacman is a private citizen who is flying in a commercial spacecraft on a voyage he paid for—not a government-agency astronaut on a taxpayer-funded trip like every space walker before him. Conceived in collaboration with Elon Musk’s SpaceX and launched atop one of the company’s Falcon 9 rockets on Tuesday, Isaacman’s five-day Polaris Dawn mission is the first of three journeys that have been planned to advance the state of the art in human spaceflight. The mission is also raising money for St. Jude Children’s Research Hospital.

Polaris Dawn had already marked its first historic milestone mere hours after launch when it fired Dragon’s thrusters to raise the spacecraft’s swooping elliptical orbit and reached more than 1,400 kilometers in altitude at its peak. That’s the farthest from Earth any human has ventured since the 1970s, when the last of the Apollo lunar missions left the entire planet in the rearview on the way to the moon. And on Wednesday, after six orbits at that dizzying height—which exposed the crew to higher levels of cosmic radiation and an elevated risk of encounters with hazardous space debris—the Dragon fired its thrusters again to push itself into a lower, safer orbit, where the space walk would take place.