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The crew of SpaceX's Polaris Dawn spacecraft has returned home after completing a five-day mission in orbit that saw the world's largest satellite discovered. first commercial spacewalk — splashed down in the Gulf of Mexico.
The Crew Dragon capsule with four astronauts on board landed off the coast of Dry Tortugas, Florida, at 3:37 a.m. ET Sunday.
Polaris Dawn Mission went down in history as it reached a higher altitude than any human had reached in five decades. The spacewalk, conducted early Thursday morning, also marked the first time such an endeavor had been completed by a privately funded and operated mission.
However, returning to Earth is one of the most dangerous stages of any space mission.
To return home safely, the Crew Dragon capsule performed what's known as a “de-orbit burn,” orienting itself and preparing to break through the thickest part of Earth's atmosphere.
The spacecraft then reached extremely high temperatures — up to 3,500 degrees Fahrenheit (1,900 degrees Celsius) — due to the pressure and friction caused by the impact with the air, while still traveling at about 17,000 miles per hour (27,000 kilometers per hour). The crew, however, had to remain at a comfortable temperature, protected by the Crew Dragon's heat shield, which is located on the bottom of the 13-foot-wide (4-meter) capsule.
Air resistance began to slow the craft before the Crew Dragon deployed parachutes, further slowing its descent.
Once in the ocean, the spacecraft bobbed for a while until rescuers waiting nearby pulled it out of the ocean and onto a special boat called the Dragon's Nest. There, final safety checks were made before the crew disembarked the capsule and began the journey back to land.
Historic flight
The The crew of Polaris Down The crew includes mission commander Jared Isaacman, a billionaire and CEO of financial services company Shift4 Payments; his close friend and former U.S. Air Force pilot Scott “Kidd” Poteet; and SpaceX operations engineers Anna Menon and Sarah Gillies.
The quartet began the mission by breaking an altitude record, achieving an orbit around the Earth that extended to 870 miles (1,400 kilometers). This is the highest orbit around the Earth ever achieved by humans, breaking the 1966 record set by NASA's Gemini 11 mission, which reached 853 miles (1373 kilometers).
The crew's apogee—or farthest point from Earth—made Gillis and Menon the first women ever to fly that far from our planet.
Apogee also marked the farthest human journey since NASA's Apollo program ended in 1972.
The Crew Dragon capsule then descended to its lowest altitude to perform a spacewalk.
In an extremely dangerous event, also called a spacewalk, the Crew Dragon capsule completely depressurized before Isaacman opened the hatch, leaving the crew exposed to the vacuum of space.
Isaacman and Gillis each exited the spacecraft for about 10 minutes, conducting a series of tests to evaluate the functionality of their spacewalk suits, before returning inside the Crew Dragon spacecraft and locking the hatch.
The spacewalk appeared to go off without any major problems. Isaacman reported after getting his first look at the spacecraft from the outside: “We all have a lot of work to do back home, but from here it looks like a perfect world.”
The crew spent the rest of their time in orbit conducting about 40 scientific experiments and studies, including those aimed at better understanding space adaptation syndrome, a type of motion sickness characteristic of microgravity conditions.
Gillis, a professional violinist, also brought her instrument along for the mission and presented a performance of “Rey's Theme” from Star Wars: The Force Awakens. Gillis' music was sent back to Earth via SpaceX's Starlink as a test of the satellite network's potential to provide communications in space.
Menon also took the time to read a book she co-wrote called Kisses from Space to her family as well as a group of St. Jude Children's Hospital patients as part of a fundraiser.
Sunday's expected return marks the completion of the third flight into space for the dedicated Crew Dragon capsule supporting the Polaris Dawn mission.
The spacecraft, named Resilience by NASA astronauts during its first flight into space in November 2020, is called Crew-1 – flew away Inspiration 4 Mission 2021On that trip, also funded by Isaacman, he and three of his teammates orbited the Earth for three days to raise money for childhood cancer research.
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