Watch SpaceX Polaris Dawn astronauts conduct 1st private spacewalk early Sept. 12

Update for 7:41 a.m. EDT: SpaceX's private Polaris Dawn astronauts successfully performed the world's first commercial spacewalk on Sept. 12, with American billionaire Jared Isaacman and SpaceX engineer Sarah Gillis each spending ust over 10 minutes stand up out of their Dragon capsule's hatch. Read our full story and see the amazing video.

The first-ever private spacewalk will happen early Thursday morning (Sept. 12), and you can watch the historic action live.

The pioneering extravehicular activity (EVA) will be conducted by Jared Isaacman and Sarah Gillis, two members of the four-person Polaris Dawn mission, which launched to Earth orbit atop a SpaceX Falcon 9 rocket early Tuesday morning (Sept. 10).

The spacewalk is expected to start at 5:58 a.m. EDT (0958 GMT), according to SpaceX . You can watch it live here at Space.com or directly via the company . Coverage will begin around 4:58 a.m. EDT (0858 GMT).

The spacewalk will last around two hours from start to finish, SpaceX and Polaris Dawn representatives have said. That timing runs from the initial venting of the mission's Crew Dragon capsule to its repressurization.

Related: How SpaceX's historic Polaris Dawn private spacewalk will work

Crew Dragon doesn't have an airlock, so its entire interior will be exposed to the vacuum of space during the EVA. That means all four crewmembers — Isaacman, Gillis, Scott "Kidd" Poteet and Anna Menon — will don their new SpaceX EVA suits.

Only Isaacman and Gillis will exit the capsule, however. They'll do so sequentially, not simultaneously, and each will remain outside for 15 to 20 minutes, Isaacman said during a prelaunch press briefing on Aug. 26. And both of them plan to maintain contact with Crew Dragon — its newly installed "Skywalker" handrails, for example — at all times during the EVA.

"We're just not going to be just floating around," Isaacman said.

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The main goal of the spacewalk is to test the new SpaceX suits, which the company developed in house and aims to use on a variety of missions to Earth orbit and beyond.

"It's not lost on us that, you know, it might be 10 iterations from now and a bunch of evolutions of the suit, but that, someday, someone could be wearing a version of [it] that might be walking on Mars ," Isaacman said on Aug. 26. "And it feels like, again, a huge honor to have that opportunity to test it out on this flight."

Editor's note: This story was updated at 1:35 a.m. ET on Sept. 12 with the new target EVA time of 5:58 a.m. EDT.