Two private astronauts moved outside their spacecraft early Thursday morning, conducting the first-ever commercial spacewalk.
The spacewalk was the centerpiece of Polaris Dawn, a collaboration between Elon Musk’s SpaceX and Jared Isaacman, a billionaire entrepreneur who is leading the mission.
“Back at home, we all have a lot of work to do, but from here, Earth sure looks like a perfect world,” he said while standing in the hatch of the SpaceX Crew Dragon capsule with the planet above his head.
The successful operation further reinforces that space travel is no longer the exclusive province of professional astronauts working at governmental space agencies like NASA, and now neither is the derring-do of spacewalks, when astronauts are protected by just their spacesuits from airless doom. The Polaris missions — this one is the first of three — aim to accelerate technological advances needed to fulfill Mr. Musk’s hope of sending people to Mars someday.
Bill Nelson, the NASA administrator, cheered the spacewalk, which the government space agency played almost no role in.
“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,” Mr. Nelson posted on the website X.
The spacewalk officially began at 6:12 a.m. Eastern time with the flow of oxygen into the astronauts’ spacesuits. That was almost three hours later than originally planned, but the operation proceeded without a hitch.
Because there is no airlock in the SpaceX Crew Dragon spacecraft used for the flight, the only way to perform a spacewalk is to let all of the air out of the spacecraft. NASA and Soviet astronauts conducted spacewalks in a similar manner in the 1960s.
First turning a hand crank, Mr. Isaacman opened the top hatch of the capsule and moved outside, where he conducted mobility tests of his spacesuit.
For a journey that earlier had traveled to the highest orbit by humans in more than a half-century, his sojourn in the vacuum of space was brief: After a few minutes, Mr. Isaacman re-entered the capsule, and another crew member, Sarah Gillis, a SpaceX engineer, moved outside and performed the same mobility tests.
Although the two other crew members, Scott Poteet and Anna Menon, remained inside the vehicle, they were also wearing spacesuits inside the airless capsule. It was the first time that four astronauts were simultaneously exposed to the vacuum of space.
After Ms. Gillis re-entered, she closed the hatch, and the inside of the spacecraft was slowly repressurized. Less than two hours after it started, the spacewalk was over.
A key goal of the Polaris Dawn mission is the development of more advanced spacesuits that would be needed for any attempt at off-world colonization by SpaceX. During a news conference before the launch, Mr. Isaacman mused about how someone stepping onto Mars might one day wear a future version of the spacesuit that SpaceX developed for this mission.
“A huge honor to have that opportunity to test it out on this flight,” he said.
Closer to Earth, commercial spacewalks could open up other possibilities once impossible to imagine, like technicians repairing private satellites in orbit. Mr. Isaacman has even suggested that the second Polaris mission could attempt a trip to NASA’s aging Hubble Space Telescope to perform repairs and extend its life in orbit.
The spacewalks by Mr. Isaacman and Ms. Gillis were short and modest in complexity. Unlike frantic scenes in science fiction movies, they waited patiently as air was slowly evacuated from their capsule. Then they moved methodically, following a carefully planned choreography that lasted only a few minutes.
After opening the hatch manually, Mr. Isaacman pulled himself upward using a railing mounted to the top of the Crew Dragon. He never let go of the spacecraft as he performed a series of movements to test the capabilities of the spacesuits.
When his time was up, he moved back down into the Crew Dragon, and Ms. Gillis then repeated the same actions.
The Polaris Dawn crew’s cautious approach was a reminder that space is an inherently inhospitable and dangerous environment, and during spacewalks astronauts are enclosed in a small bubble of air — their spacesuits — that keep them from suffocating in the vacuum of space.
While there have been near misses during spacewalks, including during the first spacewalk by a Soviet astronaut in 1965, going outside a spacecraft is not the most dangerous part of spaceflight. No astronauts have ever died or suffered serious injury during a spacewalk. And spacewalks are not infrequent: There have been more than 270 spacewalks conducted at the International Space Station since December 1998 largely without incident. (Astronauts at the I.S.S. enter and exit the space station through airlocks, minimizing the amount of air that is released into space.)
Fatalities during spaceflight have occurred during launches, as was the case with the loss of the space shuttle Challenger and its crew in 1986, or during landings, like when the space shuttle Columbia burned up in the searing heat of re-entry through Earth’s atmosphere in 2003.
The Polaris Dawn mission has so far gone smoothly.
A SpaceX Falcon 9 rocket launched the Crew Dragon capsule and the four astronauts early Tuesday morning into an elliptical orbit that, at its highest point, was 755 miles above Earth’s surface.
That was the farthest off the planet that anyone has gone since NASA’s Apollo moon missions in the 1970s.
At that altitude, they passed through the South Atlantic Anomaly, a weak point in Earth’s magnetic field that allows high-energy charged particles from regions known as the Van Allen belts to come closer to Earth’s surface. Much of the radiation dosage from this spaceflight — equivalent to several months at the space station — occurred during these first few orbits.
Late on Tuesday, the thrusters fired to stretch its orbit to a high point of about 870 miles. That surpassed the 853-mile altitude that two NASA astronauts, Pete Conrad and Richard Gordon, reached during the Gemini XI mission in 1966, which had been the record distance for astronauts on a spaceflight not headed to the moon.
After circling Earth six times in the high orbit, the Crew Dragon returned to a lower orbit, where there is less danger from radiation and micrometeoroids.
During their spaceflight, the four crew members are conducting about 40 experiments, mostly investigating how weightlessness and radiation affect the human body. They have also tested laser communications between the Crew Dragon and SpaceX’s constellation of Starlink internet satellites.
