Astronauts aboard SpaceX Crew Dragon(a.k.a. Resilience) on Thursday (Sept. 12), performed the world's first commercial spacewalk while the spacecraft was soaring about 737 kilometers(km) above Earth during the third day of the Polaris Dawn mission to far Earth orbit. The 1 hour 46 minutes spacewalk started at 1012 UTC.
While Resilience was soaring ~737 km above Earth, Polaris Dawn crew -- Jared Isaacman, pilot Scott "Kidd" Poteet" and SpaceX mission specialists Sarah Gillis and Anna Menon -- embarked on the spacewalk(or extravehicular activity, EVA), starting with depressurization of the capsule and hatch opening which exposed the crew to the harsh void of space.
The crew wore new SpaceX-designed EVA suits that were made to be lightweight and flexible while still offering protection against the harsh, unforgiving environment in Earth's orbit. "All that stands between you and the nothingness of deep space vacuum is that [spacesuit]," SpaceX chief Elon Musk noted on X just hours after the completion of the spacewalk.
Isaacman and Sarah Gillis took turns to pop out out from Crew Dragon into the void, at about 1048 UTC and 1104 UTC respectively.
"SpaceX, back at home we have a lot of work to do, but from here it looks like a perfect world," Isaacman said as he looked down on Earth while floating upright above the Dragon hatch.
The Crew Dragon was heavily modified with a specialized hatch designed just for the mission. Skywalker -- which replaced the capsule's typical International Space Station(ISS) docking port -- features a ladder and both handholds and footholds for the Polaris Dawn astronauts to grab onto as they maneuvered around the outside of the capsule.
During his ~7 minutes 56 seconds spacewalk maneuver, Isaacman conducted a series of spacesuit mobility tests, one of Polaris Dawn's main goals. Gillis did the same during her ~7 minutes 15 seconds maneuver.
SpaceX aims to use the spacesuit on a variety of future missions both in Earth's orbit and farther into space. "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."
After Gillis completed her spacewalk and lowered into Crew Dragon, the Dragon hatch was closed at about 1114 UTC as SpaceX began repressurizing the spacecraft. The entire spacewalk lasted one hour and 46 minutes, from 1012 UTC to 1158 UTC.
"Whew! Smell that? Space," Isaacman said after the hatch was closed and the capsule began its repressurization process. "Nice job for everyone at SpaceX who made it possible."
"The Polaris Dawn spacewalk is now complete, marking the first time commercial astronauts have completed a spacewalk from a commercial spacecraft! Congratulations to @rookisaacman, @Gillis_SarahE, @KiddPoteet, @annawmenon, and to all the SpaceX teams!" SpaceX wrote on X.
SpaceX Polaris Dawn mission launched four astronauts into orbit on Tuesday (Sept. 10). Fifteen hours later, the crew made space history when they reached an altitude of 1,400.7 km, higher than any other crewed mission since the Apollo program a half-century ago. Another NASA mission, Gemini 11, previously held the altitude record for a crewed spacecraft in Earth's orbit at 1,373 km.
Polaris Dawn is also testing a new communication system that uses lasers to link up with SpaceX's Starlink satellites, a megaconstellation that provides broadband internet worldwide. The system "has the opportunity to open up an entirely new communication pathway, not just for Dragon, but for [...] Starships or other satellites or telescopes out there," Isaacman said at a press conference on Aug. 19.
"Polaris Dawn is the first mission to test @Starlink laser-based communications, using the 'Plug and Plaser' inside Dragon’s trunk to communicate with Starlink satellites throughout the mission," SpaceX wrote X, before mission launch on Tuesday.
The Polaris Dawn astronauts have also been conducting 36 different science experiments provided by 31 separate institutions. These experiments will be conducted throughout the mission, including some that will contribute data to NASA's Human Research Program, helping scientists better understand how the human body reacts to spaceflight.
The experiments conducted during Polaris Dawn, range from testing wearable devices that collect biometric data, attempts to mitigate motion sickness, and tests on eye health in microgravity. Polaris Dawn has also traveled through portions of Earth's Van Allen radiation belt, offering the opportunity to better understand how this radiation affects the human body.
"Each mission, whether the crew is comprised of commercial or NASA astronauts, provides a key opportunity to expand our knowledge about how spaceflight affects human health," Jancy McPhee, associate chief scientist for human research at NASA, said in a statement. "Information gathered from Polaris Dawn will give us critical insights to help NASA plan for deeper space travel to the moon and Mars."
Polaris Dawn is scheduled to return to Earth on its sixth day, with Crew Dragon splashing down under parachutes off the coast of Florida.