Crew of SpaceX's Polaris mission undertakes spacewalk

Four private citizens orbiting Earth in a SpaceX capsule will attempt to make history early today by completing the world's first all-civilian spacewalk.

Billionaire entrepreneur Jared Isaacman, retired Air Force Lt. Col. Scott “Kidd” Poteet and SpaceX engineers Sarah Gillis and Anna Menon make up the crew of the Polaris Dawn mission, which launched on Tuesday for a five-day flight into space.

Their spacewalk is scheduled to take place at 5:58 a.m. ET, after a delay of several hours, and will last about 20 minutes.

During the excursion, Isaacman and Gillis are expected to exit the SpaceX Crew Dragon capsule on a tether. Although they are the only ones scheduled to leave the spacecraft, all four crew members will wear and test newly developed spacesuits during the excursion. This is because the Crew Dragon does not have a pressurized airlock, so the entire capsule will be depressurized and subjected to vacuum conditions.

Overall, the Polaris Dawn mission is designed to test procedures and technologies that could be used in future long-duration space missions. During their journey, the crew members flew into the highest orbit that humans have reached since the last Apollo moon mission in 1972: 870 miles above the Earth's surface.

The flight was funded by Isaacman with an undisclosed amount.