Who are the astronauts doing the spacewalk? By Reuters

(Reuters) – SpaceX’s Polaris (NYSE: ) Dawn mission is poised to make history this week with the first privately managed spacewalk, a risky endeavor previously undertaken only by government astronauts.

Two of the mission’s four crew members will venture out of their Crew Dragon capsule into Earth orbit for a tethered spacewalk, marking the first major test of SpaceX’s new spacesuits.

The capsule has no airlock and will depressurize completely for the spacewalk, requiring all four crew members to rely on their suits for survival.

The mission, scheduled for launch at 3:38 a.m. ET (0738 GMT) on Aug. 27 from NASA’s Kennedy Space Center in Florida, is expected to last six days, with the spacewalk planned for the third day.

Here’s a look at the profile of the astronauts:

JARED ISAACMAN

Isaacman, the billionaire CEO of payments processing firm Shift4 Payments and a seasoned pilot, leads the Polaris Dawn mission and will be one of two members — along with Sarah Gillis — to perform the spacewalk outside the capsule.

He is funding the mission under his Polaris program, although he declined to disclose the total cost, estimated to be in the hundreds of millions of dollars.

The mission will be his second foray into space, after leading the first all-civilian Inspiration4 mission into Earth orbit in 2021, which he organized and funded primarily in partnership with SpaceX.

After Polaris Dawn, Isaacman has two more missions planned in the Polaris program — another flight on Crew Dragon followed by a flight on Starship, SpaceX’s next-generation rocket under development. He did not notify his crewmates or the dates for those flights.

SARAH GILLIS

Gillis trained astronauts and is now becoming one herself. She graduated from the University of Colorado Boulder with an engineering degree, started as an intern at SpaceX in 2015, and is now the company’s senior space operations engineer. Her responsibilities include training astronauts in flight safety and operations.

Gillis, Polaris Dawn’s mission specialist, has trained NASA astronauts for several missions, including the International Space Station Dragon missions Demo-2 and Crew-1 and the Inspiration4 mission in 2021.

SCOTT POTEET

Poteet, the Polaris Dawn mission pilot, had a 20-year career in the US Air Force with more than 3,200 flight hours in various aircraft, including the F-16 fighter jet.

Poteet’s involvement in the private space sector began when he was mission director for the Inspiration4 mission.

The New Hampshire native’s role on the latest mission extends beyond just piloting the spacecraft to assisting with the spacewalk, providing communications support and working with mission control.

Poteet was vice president of strategy at Isaacman’s company Shift4 until 2022, according to LinkedIn. Until 2020, he was director of business development at defense contractor Draken International, which Isaacman founded, before selling a majority stake in the firm to Blackstone (NYSE: ) in 2019.

ANNA MENON

Menon is the mission specialist and medical officer for the program and is a senior space operations engineer at SpaceX, where he manages the development of crew operations, ensuring procedures and protocols are in place for astronauts during their missions.

The former NASA biomedical flight controller will be responsible for the health and well-being of the crew during the Polaris Dawn mission, monitoring their physiological responses and providing medical care if needed.

She holds a master’s degree in biomedical engineering from Duke University.

Menon is married to Anil Menon, a former SpaceX flight surgeon who is currently a NASA astronaut in training.