Watch: Tech Billionaire Launches First Private Spacewalk from SpaceX Capsule

Tech entrepreneur Jared Isaacman and his team made history on Thursday by leading the first-ever private spacewalk conducted by non-professional astronauts. The mission, organized in partnership with SpaceX, took place hundreds of miles above Earth.

Before beginning the spacewalk, Isaacman and his crew waited for their capsule to depressurize, then opened the hatch. Isaacman, 41, who is the CEO and founder of the Shift4 credit card-processing company, has not disclosed the cost of this groundbreaking mission.

The four crew members were equipped with SpaceX’s new spacewalking suits, designed to protect them from the vacuum of space. This mission was the highlight of a five-day flight, sponsored by Isaacman and Elon Musk’s SpaceX, and represents years of work aimed at paving the way for human settlement on Mars and other planets.

Launched from Florida on Tuesday, Isaacman and his crew traveled farther from Earth than anyone since NASA’s Apollo moon missions. However, the spacecraft’s orbit was later reduced to 460 miles (740 kilometers) in preparation for the spacewalk.

The initial spacewalking test was expected to last around two hours and involved more stretching and maneuvering than actual walking. Isaacman’s task was to remain attached to the capsule while testing the flexibility and durability of the new spacesuit. After about 15 minutes outside, SpaceX engineer Sarah Gillis was set to take over and perform similar tests.

While spacewalking is considered one of the most dangerous aspects of space travel, along with launch and reentry, it is also seen as one of the most awe-inspiring experiences. The entire crew, including former Air Force Thunderbird pilot Scott “Kidd” Poteet and SpaceX engineer Anna Menon, underwent extensive training for this mission. Poteet and Menon stayed inside the capsule to monitor the spacewalk from their seats.