ORLANDO — A billionaire-backed series of private astronaut missions is now planning its first launch this summer that will include the first spacewalk on a commercial spaceflight.

Jared Isaacman, who led the Inspiration4 private astronaut mission that flew himself and three others for three days on a Crew Dragon in 2021, announced the Polaris Program a year ago. The program is a series of missions that will start using Crew Dragon and culminate with the first crewed Starship flight.

At the time of the announcement, the first mission, Polaris Dawn, was scheduled for as soon as the fourth quarter of 2022, but has slipped into 2023 in part because of additional time needed for training for the mission as well as schedules for other SpaceX missions.

Polaris Dawn is now scheduled to launch this summer, Isaacman said at the SpaceCom conference here Feb. 23. “We’re now just months away from flying.”

The highlight of Polaris Dawn will be a spacewalk, or EVA, the first from a Crew Dragon spacecraft or from any commercial mission. Because Crew Dragon does not have an airlock, the entire cabin will be depressurized, so all four people on board will be suited up. “As far as I’m concerned, all four crew members are doing an EVA,” he said. Two of the four will exit the spacecraft while the other two support them from inside.

The spacewalk will last about two hours, he estimated, from the time the cabin air is vented to when it is repressurized again. “We’ll see how much time we have outside the vehicle. We have a whole test protocol to go through so we can learn as much as we can about the suits.”

SpaceX has developed the suits that the Polaris Dawn crew members will wear. Neither the company nor Isaacman have disclosed details about their design, but he said that the ability to leave a spacecraft is critical for long-term plans for making humanity multiplanetary, SpaceX’s stated goal.

The knowledge of how to do spacewalks is currently limited to a few government space agencies, he argued, but needs to spread and also become more affordable. “From SpaceX’s perspective, building suits that don’t cost a lot of money, as the current generation of suits do, and can be mass produced for hundreds or thousands of people someday, is very important,” he said.

The suit will be based on the pressure suit SpaceX uses for Crew Dragon missions to protect astronauts from cabin depressurization. “That was a last line of defense. How do we build from here to something that is now primarily designed to be exposed?” he said. Those changes involve insulation, protection from micrometeroids and additional redundancy, among other upgrades.

The spacewalk is only one goal of the five-day mission. Polaris Dawn will start by temporarily raising the apogee of the spacecraft’s orbit to about 1,400 kilometers, the highest altitude for a crewed spacecraft since the last Apollo lunar mission a half-century ago. That will start about nine orbits after launch, keeping the spacecraft at the higher orbit “just long enough to get the data we need” for experiments linked to the radiation environment, Isaacman said.

Polaris Dawn will also test communications through the Starlink constellation, to see if that system can take over communications handled through traditional ground stations or NASA’s TDRS satellite network. There will be other experiments that the crew will conduct during the flight as well.

“We’re going to learn a lot,” he said of the spacesuit testing, “and we’re going to build on it for, ideally, our second missions and those that follow.”

When Isaacman announced Polaris a year ago, plans for the second mission were unclear. In September, NASA announced it had started a study with SpaceX to look at potentially using Crew Dragon to reboost the Hubble Space Telescope. Isaacman was at the briefing that announced the study and suggested that reboost mission, which might also include servicing of some kind, could be the second Polaris mission.

Isaacman said at SpaceCom that there was little information he could reveal about the ongoing study. “There’s been tons of progress on it. There’s a lot of enthusiasm,” he said. “From my perspective, it certainty builds off of Polaris Dawn. There are a lot of things we are going to do on that mission and, if they’re successful, I could certainly see us building upon it for a mission like this.”

NASA has not provided updates on the progress of the study, although in December it released a request for information about other options to reboost Hubble.

The third Polaris mission will be the first crewed flight of Starship. Isaacman said he didn’t have special insights into the first orbital launch attempt of the vehicle, although a company official said Feb. 22 they were proceeding towards a launch in March, pending a launch license from the Federal Aviation Administration.

He said he didn’t know how long after the first successful orbital launch before SpaceX would be ready to fly people on the vehicle. “They have a constellation to build out with the next generation of Starlinks,” along with other satellite customers, he said. “When they’re ready, they’ll be ready.”

Jeff Foust writes about space policy, commercial space, and related topics for SpaceNews. He earned a Ph.D. in planetary sciences from the Massachusetts Institute of Technology and a bachelor’s degree with honors in geophysics and planetary science...