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SpaceX’s Polaris Dawn crew is beginning its fifth day in orbit, having marked a few record-setting milestones on a historic journey — including the world’s first commercial spacewalk.
Conducting a spacewalk is nothing new.
NASA has been carrying out the endeavors in outer space since 1965, when the Gemini program debuted the capability for the United States.
Since then, astronauts from all over the world have used spacewalking technology to explore the moon’s surface, service the Hubble Space Telescope and help construct the International Space Station. Today, a spacewalk, also called an extravehicular activity or EVA, is still routinely used at the orbiting laboratory to allow astronauts to service and maintain its aging exterior.
But SpaceX demonstrated Thursday that conducting a spacewalk is a task that can be performed by the industrial sector, not just government astronauts. In doing so, Elon Musk’s company took a major step toward commercializing those capabilities.
It marked the first time a private mission to space attempted such an endeavor. And though the crew members didn’t venture far outside of the vehicle, they pushed boundaries and took on considerable risk.
Exposed to the void of space
During the high-risk event, the Crew Dragon capsule become entirely depressurized before the entire crew — including Shift4 Payments CEO Jared Isaacman, former US Air Force pilot Scott “Kidd” Poteet and SpaceX engineers Anna Menon and Sarah Gillis — was exposed to the vacuum of space.
Isaacman and Gillis then exited the vehicle for roughly 10 minutes each, carrying out a series of tests to understand the functionality of their EVA suits, before retreating inside the spacecraft and latching the circular hatch.
The dangers and stakes around the spacewalk were enormous.
A wrong move during a crucial “pre-breathing” process in the lead-up to the spacewalk could have put the crew at risk of getting “the bends,” or decompression sickness — a condition experienced by scuba divers that involves nitrogen bubbles forming in the blood.
This crew also put the EVA suits — designed and developed by SpaceX in just 2 ½ years — to the ultimate test. The suits had to shield them from the extreme temperatures of outer space as well as remain pressurized and funnel oxygen supplies to all four crew members.
But the spacewalk appeared to go off without any major issues. Isaacman reported after taking his first glimpse outside the spacecraft, “Back at home we all have a lot of work to do, but from here — looks like a perfect world.”
NASA Administrator Bill Nelson also offered his congratulations after the spacewalk in a post on X, formerly known as Twitter.
“Congratulations @PolarisProgram and @SpaceX on the first commercial spacewalk in history!” Nelson wrote. “Today’s success represents a giant leap forward for the commercial space industry and @NASA’s long-term goal to build a vibrant U.S. space economy.”
The four citizen astronauts will have plenty to celebrate upon their return. Even before the spacewalk, the mission had already set itself apart from other trips to orbit funded and operated by the private sector, which tend to stick to less risky mission profiles or include brief visits to the International Space Station guided by professional astronauts.
The crew also became the first group of people to venture into the lower band of the Van Allen radiation belts in five decades.
Polaris Dawn reaches the radiation belts
The Van Allen belts trap concentrations of high-energy particles that come from the sun and interact with Earth’s atmosphere, creating two dangerous bands of radiation, according to NASA.
After the crew launched into orbit atop a Falcon 9 rocket at 5:23 a.m. ET on Tuesday, the SpaceX Crew Dragon capsule immediately began to raise its position, using onboard engines to put itself into an oval-shaped orbit that extended as high as 870 miles (1,400 kilometers) from Earth.
That altitude is well into the inner band of the Van Allen radiation belts, which begin at around 600 miles (1,000 kilometers) above Earth.
The crew’s apogee — or farthest point from Earth — made Gillis and Menon the first women to travel so far from our planet.
The apogee also marked the farthest any human has traveled since NASA’s Apollo program ended in 1972, and it was the highest orbit around Earth ever achieved, besting the record set in 1966 by NASA’s Gemini 11 mission, which reached 853 miles (1,373 kilometers).
Homeward bound
After completing about six orbits around the planet at those heights with the crew safely tucked inside, the Crew Dragon capsule fired up its engines again to lower its orbital path. Thursday’s spacewalk took place as the vehicle orbited about 115 to 455 miles (185 to 732 kilometers) above Earth.
The riskiest part of the journey may be over, but the Polaris Dawn crew still has a key milestone ahead: coming home. The team is set to return to Earth, splashing down off the coast of Florida aboard the Crew Dragon capsule, as soon as this weekend.
Mission commander Isaacman — who also spearheaded and partially funded this mission to orbit — previously told CNN that the Polaris Dawn crew would have only about five or six days’ worth of life support on the vehicle.
That would mean the return to Earth could fall in the early hours of Sunday or Monday morning.
Splashdown can occur at any of seven potential locations off the East and West coasts of Florida, as with every Crew Dragon mission returning to Earth.
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