Polaris Dawn Astronauts Successfully Leave SpaceX Capsule for Historic All-Civilian Spacewalk

The crew has gone deeper into the stars than any astronaut mission since the '60s

For the first time in history, civilian astronauts have successfully completed a spacewalk.

The crew of the private Polaris Dawn mission entered the deep black void between the stars in the early hours of Thursday, Sept. 12. Video of the milestone was streamed on X, the social media platform (formerly known as Twitter) owned by SpaceX founder Elon Musk.

While only two of the four members of the crew physically left the SpaceX capsule — engineer Sarah Gillis, 30, and Jared Isaacman, the 41-year-old billionaire tech entrepreneur who is funding the flight — pilot Scott "Kidd" Poteet, 50, and medical officer Anna Menon, 38, were also suited up and exposed to the vacuum of space.

Related: SpaceX Launches Historic Polaris Dawn Mission as Civilian Crew Looks to Attempt First-Ever Private Spacewalk

That's because the spaceship does not have an airlock, so the capsule had to be opened and depressurized for all. To avoid decompression sickness, the crew had their nitrogen removed from their blood in a process pre-takeoff.

The spacewalk was one of the key goals of Polaris Dawn's mission. While standing in the hatch and looking down at Earth, Isaacman got reflective.

“Back at home, we all have a lot of work to do, but from here, it sure looks like a perfect world,” Isaacman said.

The four members of the Polaris Dawn took off in a SpaceX Dragon capsule from Florida early on Tuesday, Sept. 10.

Their goal? To fly deeper into the cosmos (870 miles, to be exact) than any other since the Gemini 11 took off in 1966.

“This is a stepping stone,” Menon, a NASA veteran, told PEOPLE earlier this year as she and the other astronauts prepared for takeoff. “It’s helping to build technologies that will get humans closer to Mars and beyond.”

“We hope to inspire future generations,” Gillis added.

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Over their five-day journey, in addition to their spacewalk, the team is planning dozens of studies and experiments while in orbit to help understand the effects of spaceflight and radiation on humans.

Menon also read her children's book, Kisses from Space, to a group of kids back on Earth via zoom, including her own and a few young cancer patients. Proceeds from the book raise money for St. Jude Children’s Research Hospital.

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