Artist’s rendering of a Polaris Dawn spacewalk
SpaceX
SpaceX’s Polaris Dawn mission is a quantum leap forward for private spaceflight, even as it demonstrates the same capabilities that government space agencies have had for decades: It also includes the first-ever extravehicular activity (EVA) conducted by a private citizen rather than a government astronaut.
This spacewalk was particularly risky: Unlike the International Space Station, SpaceX’s Crew Dragon doesn’t have an airlock, so the spacewalk would require crew members Jared Isaacman and Sara Gillis to evacuate all of the air from the capsule before blasting off into space. Not only were there no government-trained astronauts on board, but it would also be the first time that SpaceX’s new spacesuits and the spacecraft itself had been tested in this way.
All of this might not seem all that impressive: After all, astronauts regularly conduct hours-long spacewalks aboard the ISS and have been doing so for decades. Opening up a spacecraft’s entire crew capsule into space has also been done before, and was relatively common during NASA’s Gemini program in the 1960s.
So while SpaceX is reliving past achievements, that’s not the whole story. “When you’re doing something for the first time, it doesn’t matter if someone else has done it before; it’s new to you,” says Laura Forsick, an independent space industry consultant. “SpaceX has never done anything like this before, so they have no choice but to start from scratch and take small steps, because that’s the safe way to do it.”
The September 12 spacewalk went smoothly, but drew criticism from the media and the public for labeling it a spacewalk because the astronauts never fully emerged from the capsule. Instead, all participants poked their torsos out of the hatch for a few minutes in what was called a “stand-up spacewalk.” “Probably the only problem was that we didn’t communicate well with the public,” Forczyk said. “But this was a private mission, not a public mission, and we didn’t have to tell the public exactly what was going on and what was planned.”
The primary purpose of the spacewalk was to test new spacesuits; no new spacewalk suits have been used in decades, and NASA’s current supply is limited and aging. “Now that SpaceX has demonstrated that these suits are safe in microgravity, the big question is whether SpaceX is willing to sell the suits to NASA,” Forczyk said. If so, even this relatively simple test of a standing spacewalk could help overcome a major obstacle to human spaceflight.
In addition to testing spacesuits, astronauts are also taking part in a variety of health experiments designed to study the effects of space travel on the human body, from tracking bone and muscle loss during flight — a common problem for astronauts — to imaging the astronauts’ brains and other organs immediately after returning to Earth.
“Private space missions like this one can really help advance research on human health during spaceflight,” says Rihana Bokhari of the Space Health Translational Research Institute in Texas, one reason for this is that more private space missions mean more space missions overall, allowing researchers to collect more data.
“Another difference we encounter is that these subjects are not government astronauts who are in the best of health, so we’re collecting a diverse health data set that will help us prepare and create a future of living and working in space for more people, including civilians,” Bokhari said.
The Polaris Dawn spacewalkers are far from ordinary people — Isaacman has been in space once, and Gillis is SpaceX’s lead astronaut trainer — but they’re the closest thing to civilians anyone has ever performed an EVA. “They risked their lives, and it worked,” Forzik says. “SpaceX has proven they can do the first steps in EVAs, so I think they’ll continue to push the boundaries and break new ground.”
The spacecraft is due to return to Earth and splash down off the coast of Florida in the coming days, after which there will be intensive examination and evaluation of the astronauts, capsule and spacesuits. SpaceX’s next Polaris flight has not yet been scheduled, as NASA has not allowed the mission to repair the Hubble Space Telescope. But the company’s capabilities are growing rapidly, and it may only be a matter of time before it catches up with government space agencies, long the only superpowers in space.
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