The SpaceX capsule, whose crew was led by the billionaire Jared Isaacman, splashed down near the Gulf of Mexico early Sunday.
After conducting the first-ever commercial spacewalk and traveling farther from Earth than anyone in more than half a century, the astronauts of the Polaris Dawn mission returned to Earth safely early Sunday.
The SpaceX Crew Dragon capsule splashed down in the Gulf of Mexico, off the coast of Dry Tortugas, Fla., shortly after 3:30 a.m., carrying Jared Isaacman, a billionaire entrepreneur, and his crew of three private astronauts, according to a SpaceX livestream.
The ambitious space mission, a collaboration between Mr. Isaacman and Elon Musk’s SpaceX, spent five days in orbit, achieved several milestones in private spaceflight and was further evidence that space travel and spacewalks are no longer the exclusive domain of professional astronauts working at government agencies like NASA.
The Crew Dragon capsule launched on Tuesday, after delays because of a helium leak and bad weather. On board were Mr. Isaacman, the mission commander and the founder of the payment services company Shift4; Sarah Gillis and Anna Menon, SpaceX employees; and Scott Poteet, a retired U.S. Air Force lieutenant colonel.
Late on Tuesday, its orbit reached a high point of about 870 miles above the Earth’s surface. That beat the record distance for astronauts on a mission not headed to the moon, which the Gemini XI mission set in 1966 at 853 miles high, and made Ms. Gillis and Ms. Menon the first women ever to fly so far from Earth.
On Thursday, Mr. Isaacman and Ms. Gillis became the first private astronauts to successfully complete a spacewalk. The operation involved the crew letting all the air out of the spacecraft, because it had no airlock, while the other two crew members wore spacesuits inside the airless capsule. Mr. Isaacman moved outside and conducted mobility tests of his spacesuit for a few minutes before re-entering the capsule. Ms Gillis then moved outside and performed the same tests.
This was the first of three Polaris missions aimed at accelerating technological advances needed to fulfill Mr. Musk’s dream of sending people to Mars someday. A key goal of the mission was to further the development of more advanced spacesuits that would be needed for SpaceX to try any future off-world colonization.
During a news conference before the launch, Mr. Isaacman mused that one day, someone might step onto Mars wearing a version of the spacesuit that SpaceX had developed for this flight. Closer to Earth, commercial spacewalks also present other possibilities, like technicians repairing private satellites in orbit.
During the spaceflight, the four astronauts conducted about 40 experiments, mostly about how weightlessness and radiation affect the human body. They also tested laser communications between the Crew Dragon and SpaceX’s constellation of Starlink internet satellites.