SpaceX set to launch Polaris Dawn crew on daring excursion into Earth’s radiation belts
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The countdown clock is finally rolling for SpaceX’s latest mission: a bold and risky trek into Earth’s Van Allen radiation belts by a four-person crew of civilians aiming to conduct the first commercial spacewalk.
The mission, dubbed Polaris Dawn, is set to take flight as soon 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 there are more opportunities to lift off in the days ahead if technical issues or the weather causes delays.
SpaceX is live streaming the event on X, the social media platform formerly known as Twitter that SpaceX CEO Elon Musk purchased in 2022.
This launch attempt comes after several issues 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 the target date by 24 hours, then weather forecasts forced SpaceX to waive off two more attempts.
Around the same time, a Falcon 9 — the type of rocket that will power Polaris Dawn’s ride to space — malfunctioned during a routine satellite mission, prompting federal regulators to briefly stop all Falcon 9 rockets from flying. SpaceX received permission on August 30 to return to the Falcon 9 to flight.
Now, the company is trying again to kick off one of its riskiest missions to date, though weather could still thwart the upcoming launch attempt.
The latest forecast puts the odds of unfavorable conditions for a Tuesday launch at 60%, according to a post made by SpaceX on X.
Further complicating launch prospects is the fact that SpaceX doesn’t just need clear weather for the mission to take off — it needs to ensure there are calm waters and winds as the crew returns from space after their five-day excursion. Timing their return could be critical. Because carrying out a spacewalk will create a drain on oxygen supplies, the Polaris Dawn mission will have only enough life support for five or six days in space.
The ride to orbit
If weather and forecasts hold, and the countdown clock makes it to zero, SpaceX’s Falcon 9 rocket will roar to life, sending a blinding blaze and deafening blast across 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) across at its base, as the rocket tears away from the grips of Earth’s gravity.
After firing for 2 ? minutes, the bottommost part of the Falcon 9 rocket — called the first stage — will have spent most of its fuel. At that point, the first stage will detach from the rocket’s second stage as the upper portion fires up its engine and continues propelling the Crew Dragon spacecraft to faster speeds.
Meanwhile, the first stage of the Falcon 9 will be guided back to Earth to land on a seafaring platform so it can be refurbished and used again on future missions. That’s a signature SpaceX move that the company said helps reduce the cost of rocket launches.
To enter Earth’s orbit, the Falcon 9 rocket will need to hit more than 17,000 miles per hour (27,358 kilometers per hour), or “orbital velocity.” When it reaches the desired speed, the Crew Dragon will break away, left to navigate the vacuum of space using only its onboard thrusters for the remainder of the mission.
First commercial spacewalk attempt
Polaris Dawn is the brainchild of SpaceX and Jared Isaacman, the billionaire founder of financial technology firm Shift4 Payments, who made his first foray into spaceflight with the Inspiration4 mission in September 2021.
This flight, however, is not a joyride.
Isaacman and his crewmates — including close friend and former US Air Force pilot Scott “Kidd” Poteet as well as SpaceX engineers Anna Menon and Sarah Gillis — hope to rack up several superlatives on this mission.
First, the SpaceX capsule aims to carry the crew to record-setting heights for an orbit around Earth, surpassing the milestone set by NASA’s 1966 Gemini 11 mission, which reached 853 miles (1,373 kilometers). If successful, Polaris Dawn would beat that record by about 20 miles (32 kilometers).
The Polaris Dawn spaceflight would also be the highest any human has flown since NASA’s Apollo program — which ended in 1972 and cumulatively carried 24 astronauts a quarter million miles to the moon rather than stopping in Earth’s orbit.
Polaris Dawn may also mark the farthest any woman has ever gone into space.
To kick off day three of this mission, the civilian crew, while orbiting at a lower altitude of about 435 miles (700 kilometers) above Earth, will attempt a history-making spacewalk.
The endeavor will be hazardous, exposing all four crew members and the Crew Dragon’s interior to the vacuum of space. Such a situation may make it difficult to relock the vehicle’s hatch due to differences in pressure. And exposure to the vacuum may cause toxins to be released from hardware when the cabin is repressurized, though SpaceX said it has taken steps to prevent this.
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