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SpaceX's historic Polaris Dawn astronaut mission has been delayed again.
Polaris Dawn was originally scheduled to launch early Monday morning (Aug. 26) from NASA's Kennedy Space Center in Florida, but SpaceX pushed things back a day to perform more preflight checkouts. The company then called the planned Tuesday (Aug. 27) attempt off after detecting a helium leak, targeting Wednesday (Aug. 28) instead. But now Mother Nature has foiled that plan.
"Due to unfavorable weather forecasted in Dragon's splashdown areas off the coast of Florida, we are now standing down from tonight and tomorrow's Falcon 9 launch opportunities of Polaris Dawn. Teams will continue to monitor weather for favorable launch and return conditions," SpaceX announced Tuesday evening via X.
Polaris Dawn will send four people to Earth orbit in a SpaceX Crew Dragon capsule, which will depart the planet atop one of the company's Falcon 9 rockets.
Related: Polaris Dawn: Everything you need to know about the 1st mission of the Polaris Program
The crewmembers are commander Jared Isaacman, pilot Scott "Kidd" Poteet and mission specialists Sarah Gillis and Anna Menon. Isaacman is a billionaire entrepreneur who's funding Polaris Dawn; Poteet is a former lieutenant colonel in the U.S. Air Force, and Gillis and Menon are both SpaceX engineers.
The upcoming mission will make history in several ways. Isaacman and Gillis will conduct the first-ever private spacewalk, for example, and Polaris Dawn aims to send the Dragon to a maximum altitude of about 870 miles (1,400 kilometers) — higher than any crewed mission since the Apollo era.
SpaceX has not yet announced a new target launch date for Polaris Dawn, which will spend about five days circling our planet. But, as the company's Tuesday-evening X post makes clear, both Wednesday and Thursday (Aug. 29) are out, so Friday (Aug. 30) is now the earliest possible liftoff day.
Polaris Dawn will be the first spaceflight for Poteet, Gillis and Menon. Isaacman flew to orbit in September 2021, on SpaceX's pioneering Inspiration4 mission. The billionaire funded and commanded that effort as well, and plans to do the same for two additional missions after Polaris Dawn.