SpaceX was scheduled early Tuesday to launch a four-person crew farther than any human has flown since the end of the Apollo missions until a helium leak postponed the Polaris Dawn liftoff until later in the week at the earliest.
"Teams are taking a closer look at a ground-side helium leak on the Quick Disconnect umbilical. Falcon and Dragon remain healthy and the crew continues to be ready for their multi-day mission to low-Earth orbit," SpaceX wrote in an updated post hours before the scheduled launch. "Next launch opportunity is no earlier than Wednesday."
The crew is led by billionaire philanthropist Jared Isaacman and also includes two of the first SpaceX employees to travel to space, Medical Officer Anna Menon and Mission Specialist Sarah Gillis. Retired U.S. Air Force Lit. Col. Scott "Kidd" Poteet will pilot Polaris Dawn.
"We're officially scrubbed for today, but the SpaceX team is doing awesome work to ensure all systems are 100% ready for launch!" Gillis wrote in a post on X.
SpaceX founder Elon Musk addressed crew safety earlier Monday in a post on X before the launch was scrubbed.
"Crew safety is absolutely paramount and this mission carries more risk than usual, as it will be the furthest humans have traveled from Earth since Apollo and the first commercial spacewalk!" Musk added, while warning that "If any concerns arise, the launch will be postponed until those concerns are addressed."
Once the crew aboard the SpaceX Dragon capsule is launched from Launch Complex 39A at Florida's Kennedy Space Center, they will spend five days orbiting Earth and will conduct the first commercial spacewalk in history.
The Polaris Dawn crew will fly to an initial maximum altitude of about 870 miles before dropping back to a lower cruising orbit. The maximum height is well into the inner band of Earth's Van Allen radiation belts, which start at around 600 miles in altitude.
The all-civilian crew will conduct a spacewalk on the third day to test the function of SpaceX's new spacesuits, which feature enhanced thermal control materials and technologies. The entire spacewalk from cabin depressurization through repressurization will last approximately two hours.
The Dragon capsule does not have an airlock so the spacewalk will take place closer to Earth, about 435 miles in altitude, where the astronauts will be exposed to the vacuum of space.
On the fourth day, the crew will connect to SpaceX's Starlink satellite network to transmit a "surprise" message down to Earth, before preparing to return for a splashdown at one of seven sites off the coast of Florida.
Isaacman, who is funding the mission, is making his second personal launch into orbit. The entrepreneur also funded and flew on Inspiration4 in 2021. This latest mission will raise money to support St. Jude Children's Research Hospital. On Inspiration4, the mission raised $250 million for the organization.
"It takes a massive team effort to bring a mission like Polaris Dawn to life. Together, we're making incredible progress for the future -- both in space and here on Earth," Isaacman wrote Sunday in a post on X. "We can do both."
