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The Polaris Dawn crew members landed at NASA’s Kennedy Space Center (KSC) on August 19, 2024, with just one week to go until their launch into space. Polaris Dawn is SpaceX’s second private crewed mission funded by American billionaire Jared Isaacman and the first of at least three space missions he hopes to launch under the “Polaris” program.
The launch follows Isaacman’s 2021 Inspiration4 mission, in which he and three other citizens made the first-ever civilian spaceflight. Inspiration4 raised $250 million for St. Jude Children’s Research Hospital in Memphis, Tennessee, and Isaacman hopes to build on that momentum with the three Polaris missions. Starting with Dawn, Isaacman sees the Polaris program as a pioneering vehicle for private spaceflight and a demonstration of the scientific returns of getting inexpensive astronauts into space. As part of that endeavor, Isaacman and the rest of the Polaris Dawn crew will fly farther from Earth than any other human in half a century and conduct the first extravehicular activity (EVA) to test SpaceX’s new spacesuits.
The mission is scheduled to launch no later than August 26 from KSC’s Launch Complex 39A. Isaacman, the mission’s captain, is strapped to the same Crew Dragon crew as Inspiration4 and will fly to orbit on a Falcon 9 rocket with fellow Polaris Dawn crew member Scott “Kid” Poteet, a retired U.S. Air Force (USAF) lieutenant colonel, serving as the mission pilot. Sarah Gillis and Anna Menon, both SpaceX’s chief space operations engineers and the first employees to launch to space on one of the company’s rockets, are serving as mission specialists.
Polaris Dawn was originally scheduled to launch in 2022, but it was delayed several times as the mission’s hardware was still under development. In particular, the team was waiting for SpaceX’s new extravehicular activity (EVA) suit to be designed and produced and for the handrail/ladder to be completed that would attach to the Crew Dragon hatch during a spacewalk. In the meantime, Isaacman and the team have been busy training for their mission. In the three years since Inspiration4’s success, the crew has completed a range of endurance and team-building exercises, including mountain climbing, skydiving, scuba diving and high-G-beam flights, and the team’s teamwork has become apparent. “It was some of the hardest training I’ve ever had,” said Poteet. Poteet has flown fighter jets in the U.S. Air Force for 20 years, and says he’s completed about 1,400 hours of simulator training during that time. Over the past two years, he and the rest of the Polaris Dawn crew have completed nearly 2,000 hours of similar training. “I can’t imagine a more qualified crew than these three individuals responsible for preparing this mission,” Poteet told reporters.
Artist’s impression of the world’s first private spacewalk – Image: Polaris/SpaceX
The crew also has full confidence in the Crew Dragon space capsule. It’s SpaceX’s first crewed launch since a Falcon 9 rocket was temporarily grounded last month after the vehicle’s second stage failed, resulting in the loss of 20 Starlink satellites. “SpaceX has done a great job of keeping us informed every step of the way,” Menon said Monday. “We spoke to SpaceX within seconds of this happening, and then we were briefed every day as SpaceX addressed the issue, looked into it, tried to understand what was going on and then resolved it very quickly. I would say that was really a confidence-building exercise. I think, you know, as a SpaceXer, that didn’t surprise me at all. That’s how SpaceX does business, they make sure they look at all the data and get to the root cause and then develop whatever solutions are needed to get to the other side. So I think it was just a confidence-building journey,” Menon said.
Polaris Dawn will spend five days in space, launching into an elliptical orbit around Earth, where Dragon will complete several orbits before increasing its maximum altitude, or apogee, to about 900 miles, higher than any human has flown since the last Apollo mission in 1972. Of the nearly 40 experiments in the crew program, most will be conducted at that altitude. One, for example, is a laser communications test that uses SpaceX’s Starlink satellite network to send a message back to Earth. “You might think that getting internet is as easy as flipping a switch and turning on your internet, but that’s not the case,” Gillis told reporters. “We’re talking about a laser sending information to a Starlink satellite that’s rapidly moving in its orbit to Earth and then back again. It’s been a fantastic development effort by the SpaceX team, and personally, I’m particularly interested in this development effort and we have a special message that we’re going to share with the world using this technology.”
A key part of the Polaris Dawn mission is testing SpaceX’s new extravehicular activity (EVA) suit. The suit looks like a thicker version of SpaceX’s previous spacesuit, which was designed for use inside the spaceship only. But the new suits must function outside the spaceship, so they feature improved materials, a thermal management system, and a new coating on the helmet visor. They also have information displays and cameras. Once EVA day arrives and the crew locks their spacesuits to open the Dragon hatch, they have about two hours between depressurizing the cabin and completing the suit test. Gillis explained the procedure, which will see two of the four crew members fully exit the vehicle: “About an hour into orbit, we will begin preparing for EVA, starting with a pre-breath protocol. This pre-breath protocol is actually designed to reduce the risk of decompression sickness when we deflated the spacesuits. So, after an hour, we will push the capsule down a little bit and over the course of about 45 hours we will slowly reduce the cabin pressure and increase the oxygen concentration to reduce the risk. On the second day of the flight, we are pressed into the suits and we do a navigation demonstration where we go through the sequence and movements in the spaceship to make sure we haven’t missed anything in our training and that we are confident before we go out for launch.”
Flight day three is the spacewalk itself. So that morning we did system checks on both the life support system and the suits before we were all pressurized to 100 percent oxygen. We completed our final pre-breath with 100 percent oxygen before venting the spacecraft. Once in vacuum, EV1 will open the hatch before EV1 and EV2, one by one, come out and complete the test array that Jared mentioned for the suit’s mobility goals. Once that’s done, EV2 will close the hatch and we’ll move on to pressurizing the spacecraft and then we’ll continue with the science and research for the rest of the mission. The details of the next two Polaris missions are still being developed, but Isaacman has big plans. “The second mission will build on what we learned from the first,” he said. “The third mission will be the first crewed flight of Starship.”
source: Space.com website
