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The crew of SpaceX’s Polaris Dawn spacecraft is on its way home and preparing to cap its five-day mission into orbit – which included the world’s first commercial spacewalk – with a splashdown in the Gulf of Mexico.
The Crew Dragon capsule, carrying four astronauts, is scheduled to land off the coast of Dry Tortugas, Florida, at 3:36 a.m. ET on Sunday. SpaceX will broadcast a livestream of the group’s return, which is scheduled to begin about an hour before splashdown.
The Polaris Dawn mission has already made history by reaching a higher altitude than any human has reached in five decades, and a spacewalk early Thursday morning marked the first time such an endeavor has been accomplished by a privately funded and operated mission.
But the journey is not over yet. And the return to Earth is one of the most dangerous parts of any space mission.
To reach home safely, the Crew Dragon capsule will perform a so-called “deorbit burn” in which it prepares to penetrate the densest part of the Earth’s atmosphere.
The spacecraft will then reach extremely hot temperatures – up to 1,900 degrees Celsius – due to the pressure and friction created by the impact with the air, while still traveling at around 27,000 kilometers per hour. The crew should, however, remain at comfortable temperatures, protected by the Crew Dragon’s heat shield located at the bottom of the 4-meter-wide capsule.
The resistance against the air initially slows the vehicle down before the Crew Dragon deploys parachutes that further slow its descent.
After impact with the ocean, the spacecraft will briefly float in the water while rescue teams waiting nearby prepare to pull it out of the sea and onto a special boat, the “Dragon’s Nest.” There, final safety checks will be carried out before the crew can exit the capsule and begin the journey back to land.
A historic flight
The Polaris Dawn crew includes mission commander Jared Isaacman, the billionaire CEO of financial company Shift4 Payments, his close friend and former US Air Force pilot Scott “Kidd” Poteet, and SpaceX operations engineers Anna Menon and Sarah Gillis.
The quartet launched this mission with a record altitude, reaching an Earth orbit of up to 1,400 kilometers. This is the highest Earth orbit ever reached by humans, surpassing the 1966 record set by NASA’s Gemini 11 mission, which reached 1,373 kilometers.
The crew’s apogee – or the farthest point from Earth – made Gillis and Menon the first women to ever fly so far from our planet.
The apogee point also marked the furthest journey undertaken by a human since the end of NASA’s Apollo program in 1972.
The Crew Dragon capsule then reduced its altitude to perform the spacewalk.
This high-risk event, also known as an extravehicular activity or EVA, completely depressurized the Crew Dragon capsule before Isaacman opened the hatch and exposed the group to the vacuum of space.
Isaacman and Gillis exited the vehicle for about ten minutes at a time and performed a series of tests to test the functionality of the EVA suits, then retreated into the Crew Dragon spacecraft and locked the hatch.
The spacewalk apparently went without any major problems. Isaacman reported after taking a first look out of the spacecraft: “We all still have a lot of work to do at home, but from here it looks like a perfect world.”
The crew spent the rest of its time in orbit conducting nearly 40 scientific experiments and research projects, including some aimed at better understanding space adaptation syndrome, a form of microgravity-specific motion sickness.
Gillis, a trained violinist, also brought her instrument to the mission and delivered a rendition of “Rey’s Theme” from “Star Wars: The Force Awakens.” Gillis’ music was beamed back to Earth using SpaceX’s Starlink to test the satellite network’s potential to provide connectivity in space.
Menon also took the time to read a book she co-wrote, titled “Kisses From Space,” to her family and a group of patients at St. Jude Children’s Hospital as part of a fundraiser.
The expected return on Sunday marks the completion of the third space trip of the Crew Dragon capsule, which powers the Polaris Dawn mission.
The spacecraft — named “Resilience” by the NASA astronauts aboard its first trip into space in November 2020, called Crew-1 — flew the 2021 Inspiration 4 mission. That trip, also funded by Isaacman, saw him and three crew members orbit the Earth for three days as part of a fundraiser for pediatric cancer research.
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