SpaceX’s Polaris Dawn mission began early Tuesday morning (10), launching a crew of four civilian astronauts into orbit. And hours later, they made history: they reached the highest orbit around Earth, surpassing a record set in NASA’s early days.
The company confirmed that SpaceX’s Crew Dragon spacecraft carrying the crew reached its maximum altitude of 878.7 miles (1,400.7 kilometers) at 10:19 p.m. ET on Tuesday. That distance surpassed the record set by NASA’s Gemini 11 mission in 1966, which reached 878 miles (1,373 kilometers) during its journey around Earth.
NASA’s Apollo missions traveled farther, but they didn’t enter a traditional orbit around Earth. They were destined for the moon, which is 250,000 miles away. The Polaris Dawn mission also marks the farthest journey a human has made since the last Apollo mission in 1972 — and the farthest into space a woman has ever traveled.
An unprecedented spacewalk
SpaceX and the Polaris Dawn crew may be celebrating their milestone, but the riskiest tasks are yet to come on this five-day mission — which is designed to push the boundaries of commercial space exploration and help test technologies that SpaceX could use on excursions deeper into the cosmos.
On Thursday morning (12), the Polaris Dawn team — which includes Jared Isaacman, CEO of Shift4 Payments and the mission’s financier; his close friend and former U.S. Air Force pilot Scott “Kidd” Poteet; and SpaceX engineers Anna Menon and Sarah Gillis — will attempt the first commercial spacewalk.
The groundbreaking event, scheduled to begin on the crew’s third day in space, is expected to occur as they orbit about 700 kilometers above Earth.
Isaacman, Menon, Poteet and Gillis will be exposed to the vacuum of space as their Crew Dragon capsule is depressurized and a circular hatch is opened. And two crew members, Gillis and Isaacman, will exit the spacecraft during the roughly two hours the vehicle will remain with its door open to the vast expanse of space.
The crew will be protected from the unforgiving void only by SpaceX’s new Extravehicular Activity (EVA) suits. The spacesuits were designed and developed in 2.5 years, which is incredibly fast by aerospace standards.
By comparison, NASA has been trying for more than a decade to secure replacements for the International Space Station’s aging spacesuits. Those suits were designed 40 years ago.
The Crew Dragon capsule is already putting the crew through a lengthy “pre-breathing” process, which prepares the astronauts’ bodies for the spacewalk. It works by slowly removing nitrogen from the crew members’ blood so that the gas doesn’t form bubbles in the bloodstream as the pressure inside the vehicle changes.
The pre-breathing process is intended to prevent decompression sickness — the same dangerous and potentially fatal illness that divers can experience if they attempt to surface too quickly.
The pre-breathing protocol that the Polaris Dawn crew is undergoing is completely different from the one performed on the International Space Station. The space station has special air compartments where astronauts can perform a quick pre-breathing process before beginning their spacewalks. It only takes a few hours.
The Polaris Dawn crew’s pre-breathing routine, however, will last about 45 hours, Gillis told CNN as the oxygen content in the cabin slowly increases while the pressure decreases.
“What’s really cool about this pre-breathing profile is that in many ways it’s much less risky than the standard on the space station,” Gillis told CNN . “It’s like opening a can of soda — and you want to open the can and have none of the bubbles come out because the pressure outside the can is the same as the pressure inside.”
By decreasing the pressure inside Crew Dragon, Gillis said, and donning their spacesuits at a time when ambient pressure equals suit pressure — crew members can better mitigate any risk of unwanted bubbles.
The biggest challenge comes after the spacewalk is over: closing the hatch aboard the Crew Dragon capsule, restoring pressurization to normal, and returning safely to Earth.
“You should be nervous about this mission,” former NASA astronaut and SpaceX adviser Garrett Reisman told CNN in August. “Anytime you try something for the first time, there are significant risks. I’ll be much more at ease when they’re back in the capsule, with the hatch closed and locked.”
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This content was originally published in SpaceX’s Polaris Dawn mission breaks record; the most dangerous part is yet to come on CNN Brasil.
Source: CNN Brasil
Charles Grill is a tech-savvy writer with over 3 years of experience in the field. He writes on a variety of technology-related topics and has a strong focus on the latest advancements in the industry. He is connected with several online news websites and is currently contributing to a technology-focused platform.
