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The crew of SpaceX’s Polaris Dawn spacecraft is home, capping off 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, landed off the coast of Dry Tortugas, Florida, at 3:37 a.m. ET on Sunday.
The Polaris Dawn mission 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 return to Earth is one of the most dangerous parts of any space mission.
To reach home safely, the Crew Dragon capsule performed what is known as a “deorbit burn,” orienting itself as it prepared to cut through the densest part of Earth’s atmosphere.
The spacecraft then reached extremely high temperatures – up to 1,900 degrees Celsius – due to the pressure and friction caused by the impact with the air, while still traveling at around 27,000 kilometers per hour. The crew, however, was supposed to remain at comfortable temperatures, protected by the Crew Dragon heat shield located at the bottom of the 4-meter-wide capsule.
The drag against the air slowed the vehicle’s speed before the Crew Dragon opened parachutes that further slowed the descent.
After impact with the ocean, the spacecraft drifted briefly in the water until rescue teams waiting nearby pulled it out of the sea onto a special boat, the “Dragon’s Nest”. There, final safety checks were carried out before the crew left the capsule and began the journey back to land.
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 remainder of their 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.
