The pair left the Crew Dragon craft in turn, with Isaacman going first. While outside of the vehicle, they conducted a number of motions to test out the mobility of their suits, designed by the Elon Musk-led company.

“Back at home we have a lot of work to do but from here, it looks like a perfect world,” Isaacman said shortly before 7 a.m. New York time, as he emerged out of the nose of the vehicle and looked down at the Earth below him.

The SpaceX crew didn’t “walk” in the sense of the Apollo-era astronauts on the moon, rather they partially emerged from the capsule, performed tests and returned inside. 

The Polaris Dawn mission also made history on Tuesday when the SpaceX Dragon capsule reached a peak altitude of 1,400 kilometers (870 miles) above Earth, sending the crew farther than any humans have traveled since the moon landings. 

Before the spacewalk, the capsule lowered its altitude to between 195 and 737 kilometers (121 and 458 miles).

The space walk served as the main event for the ongoing mission in Earth orbit. Launched early Tuesday morning, the flight’s primary goal is to test SpaceX’s spacesuits in the vacuum of space. 

Before now, spacewalking has been an exclusively government job, performed by astronauts from government agencies or nation states, but Isaacman and Gillis are private astronauts. Isaacman provided development funding for the mission, but has declined to say how much he contributed.

Polaris Dawn consists of a four-person crew, including Isaacman and Gillis, as well as Anna Menon, another lead SpaceX engineer, and Scott “Kidd” Poteet, Isaacman’s close friend and a former US Air Force pilot. 

During the spacewalk, Menon and Poteet remained inside the spacecraft. However, all four wore SpaceX’s suits throughout the maneuver, as the spacecraft’s hatch remained open, exposing the full interior to the vacuum of space. Menon and Gillis now hold the record for women who have traveled the farthest from Earth.

Back inside the craft after the space walk, the crew restored cabin pressure to end the space walk demonstration. They’ll soon make preparations for the journey back to Earth around the fifth day of flight. They’re slated to splash down in the ocean, where they’ll be recovered by SpaceX.

Because of the distance the crew is traveling, they’ve been exposed to a much higher radiation environment than what most astronauts experience while traveling to the International Space Station in low-Earth orbit. That will allow SpaceX to collect critical research about how the space environment affects the human body.

Polaris Dawn and Dragon at 1,400 km above Earth – the farthest humans have traveled since the Apollo program over 50 years ago pic.twitter.com/rRDeD1dY1e

— SpaceX (@SpaceX) September 11, 2024

SpaceX hasn’t said what specifically it hopes to use spacewalking for in the future. NASA astronauts perform spacewalks primarily to fix or update hardware on the outside of the International Space Station. 

“I think we’ll be really interested to see where the company does take it,” Gillis said in an interview ahead of the flight. “This is the first step, and this is a really important step.”

(Updates with mission details in fourth and eleventh paragraphs.)