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The countdown is finally on for SpaceX’s latest mission: a daring and risky expedition into Earth’s Van Allen radiation belts by a crew of four civilians to conduct the first commercial spacewalk.
The mission, called Polaris Dawn, is scheduled to launch as early as 3:38 a.m. ET Tuesday. Backup launch times are available at 5:23 a.m. ET and 7:09 a.m. ET, and alternate launch times are possible in the coming days if technical issues or weather cause delays.
SpaceX is streaming the event live on Xthe social media platform formerly known as Twitter that SpaceX CEO Elon Musk purchased in 2022.
The launch attempt comes after several issues that hampered the Polaris Dawn crew’s efforts to get off the ground in late August. First, a problem with ground equipment at the launch site pushed back the planned date by 24 hours, and then weather forecasts forced SpaceX to scrap two more attempts.
Around the same time, a Falcon 9 — the type of rocket that will power Polaris Dawn’s journey into space — malfunctioned during a routine satellite mission, prompting federal regulators to briefly shut down all Falcon 9 rockets to fly. SpaceX received authorization on August 30 to return the Falcon 9 to flight.
Now the company is attempting again to launch one of its riskiest missions yet, though weather conditions could still be challenging. thwart the upcoming launch attempt.
The latest forecast puts the probability of unfavorable conditions for a launch on Tuesday at 60 percent, according to a SpaceX post on X.
The launch outlook is further complicated by the fact that SpaceX not only needs clear weather for the mission to take off, but also needs to ensure that the waters and winds are calm when the crew returns from space after their five-day excursion. The timing of the return could be crucial. Because a spacewalk will deplete oxygen supplies, the Polaris Dawn mission will only have enough life support for five or six days in space.
The journey to orbit
If the weather and forecast hold and the countdown reaches zero, SpaceX’s Falcon 9 rocket will burst into life, sending a blinding flame and a deafening explosion over the launch site at NASA’s Kennedy Space Center in Florida.
The crew will ride atop the rocket, strapped inside an igloo-shaped SpaceX Crew Dragon capsule, which measures about 13 feet (4 meters) in diameter at its base, as the rocket tears itself away from the grip of Earth’s gravity.
After 2 1/2 minutes of flight, the lower part of the Falcon 9 rocket, called the first stage, will have used up most of its fuel. At that point, the first stage will detach from the rocket’s second stage while the upper part will ignite its engine and continue propelling the Crew Dragon spacecraft at faster speeds.
Meanwhile, the Falcon 9’s first stage will be brought back to Earth to land on a sea platform so it can…
