In another milestone for SpaceX, billionaire Jared Isaacman and the company’s crew trainer, Sarah Gillis, took turns floating just outside the Crew Dragon capsule early Thursday morning in the first privately funded spacewalk in the history of space exploration.
Taking his first unobstructed view of Earth, 458 miles below, Isaacman marveled at the serene, boundary-free view. “Back home, we all have so much work to do. But from up here, it certainly looks like a perfect world,” he said.
and Polaris Dawn With the spacecraft’s hatch open and airless inside the SpaceX Crew Dragon, crew members Anna Menon and Scott Poteat monitored safety tethers and umbilical cables, while Isaacman used a scaffolding-like “Skywalker” framework that extended from the hatch for stability before stepping out into space at about 6:51 a.m. EDT.
While his feet were just outside the hatch, he was not “free-floating” from the Crew Dragon. The SpaceX-designed pressure suit was not equipped with its own oxygen supply or other life support systems, relying instead on a 12-foot-long umbilical cable that provided air, power and communications.
Floating one by one just outside the hatch, Isaacman and Gillis tested the comfort and mobility of their pressurized extravehicular activity (EVA) suits, moving their arms, hands and legs in different positions to see how much effort it took to perform basic tasks.
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“We’ll be using a variety of mobility aids that the SpaceX team has developed that will give the appearance of dancing,” Isaacman said before the launch. “Our goal is to learn as much as we can about the suit and provide that information back to our engineers to help evolve future suit designs.”
Cameras mounted inside and outside Crew Dragon, as well as others attached to the astronauts’ helmets, provided wide-angle images of space and the Earth below as the spacecraft traveled in an elliptical orbit that ranged from a low 121 miles per hour to a high 458 miles per hour (200 miles higher than the International Space Station).
“It’s amazing,” Isaacman said, taking in the view after completing his mobility test.
The walk was announced to have concluded at 7:58 a.m. EDT. SpaceX said everyone reported feeling “in good health” after the walk ended.
The purpose of the 1 hour, 46 minute spacewalk was to help SpaceX engineers perfect a low-cost, easy-to-manufacture spacesuit for future commercial astronaut flights to the Moon and Mars aboard the company’s Super Heavy Starship rocket.
SpaceX
“I think this effort to develop an affordable spacewalk suit that can be mass-produced is incredibly worthwhile,” said Isaacman, who chartered SpaceX’s first fully commercial orbital flight in 2021. “In the future, we’ll have a fleet of Starships on Mars, and their crews will need to be able to get out of their spacewalks and walk around and do important things.”
Isaacman, Poteet, Menon and Gillis launched from Kennedy Space Center on Tuesday aboard a SpaceX Falcon 9 rocket. The crew quickly achieved their first major goal of the flight, climbing to an altitude of 870 miles, the highest for a crewed spacecraft since the Apollo moon missions 60 years ago.
The highest point of the orbit, or apogee, was then lowered to 458 miles for the spacewalk and the remainder of the five-day mission.
To prevent decompression sickness (also known as “decompression sickness”) as the crew transitioned from sea level pressure to the 5 psi reduced pressure inside the spacesuits and back again, flight controllers began a process of increasing oxygen levels in the cabin immediately after launch and over the course of 45 hours, while gradually reducing air pressure to remove nitrogen from the crew’s bloodstream.
“We don’t anticipate experiencing[decompression sickness]because a tremendous amount of preparation has gone into developing this pre-breathing protocol, and the risk has been greatly mitigated,” said Menon, a former NASA biomedical flight controller, “but we’re prepared if it is necessary.”
It appears that such measures were not necessary.
SpaceX
Crew Dragon has no airlock and its life support systems are not designed to support spacewalks. The modifications required included “adding more oxygen to the spacecraft so that it can provide oxygen through cords to all four suits for the entire duration of the spacewalk,” Gillis said.
“Upgrades and additions have been made to the environmental sensing equipment on board the spacecraft to provide really good insight both before, during and after exposure to a vacuum, and… a brand new system, the Nitrogen Suppression System,” has been introduced to return the spacecraft to normal pressure after a spacewalk.
In addition to the Skywalker platform extending just outside the forward hatch, a motorized system was added to assist in opening and closing the hatch, and the seal was improved to ensure an airtight seal.
NASA astronaut Ed White performed the first American spacewalk on June 3, 1965, floating freely from the Gemini 4 capsule at the end of a long tether. Since then, NASA astronauts, Russian astronauts, Chinese astronauts and astronauts from Space Station partner countries have conducted more than 470 government-sponsored spacewalks.
Isaacman said the iconic photo of White floating outside the Gemini capsule with Earth and space in the background was inspirational, but he and Gillis dismissed the idea of ​​floating away from Crew Dragon — and that was as planned.
“We’re not going to do an Ed White float,” Isaacman told CBS News before the launch. “It might look cool, but it’s not going to help SpaceX learn a lot about how (the suit) performs. It’s not going to help or be useful in figuring out how to work in the suit.”
To do so, he and Gillis will work through a “matrix” of planned movements to get a feel for how the suit’s multiple joints move under pressurization, test the performance of an innovative head-up display in the helmet, and better understand how the air-cooled suit will cope with the extreme temperatures of space and a variety of other factors.
SpaceX
“The suit is packed with all sorts of technology, including heads-up displays, helmet cameras and a completely new structure that improves range of motion,” Gillis said. “The suit is insulated throughout and has a copper and indium tin oxide visor that provides both thermal and solar protection.”
She added, “There’s redundancy in everything – the oxygen supply to the suit, all the valves, the seals throughout the suit. This is an incredible suit.”
The head-up display, which projects key data onto the bottom left corner of the helmet’s visor, is a feature not available on NASA’s decades-old space station suits.
“When we’re in a spacewalk, we know the suit, the pressure, the temperature, the relative humidity, and how much oxygen we used during the spacewalk. So it’s a key part of the telemetry. And being able to see that in any light is really cool.”
The Polaris Dawn mission is the first of three Isaacman is planning in collaboration with Elon Musk: the second flight will be another Crew Dragon mission, and the third will be the first crewed flight of SpaceX’s giant Super Heavy Starship rocket, currently under development in Texas.
It’s unclear how much Isaacman is paying for the flights, or how much SpaceX is funding from its own sources. Asked if he could provide details, Isaacman said, “No way.”
The mission will be the fifth flight of SpaceX’s Crew Dragon into commercial orbit and the 14th including NASA flights. The mission is scheduled to last five days and end with a splashdown off the coast of Florida.
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