The four-member crew of what is set to be an historic spaceflight arrived in Florida on Monday. Against the backdrop of clear blue skies and summertime humidity, the quartet of astronauts descended from the camouflage clad Dassault Alpha jets owned by the mission’s commander, Jared Isaacman.
The crew, which also includes former retired U.S. Air Force pilot, Scott “Kidd” Poteet, and two SpaceX Lead Space Operations Engineers, Anna Menon and Sarah Gillis, will not only fly further beyond Earth than anyone since the Apollo era, but is also set to perform the first commercial spacewalk.
“It’s been two-and-a-half years since we announced the Polaris Program and Polaris Dawn,” Isaacman said. “It’s been a really exciting journey of development and training.”
The mission is the first of three flights that make up the Polaris Program. The parameters of the second mission haven’t been fleshed out publicly, but Isaacman said from the beginning that the third mission will be the first crewed flight of a SpaceX Starship rocket.
“At twice the thrust of the Saturn V [rocket], it could very well be the 737 of human spaceflight someday, but it will certainly be the vehicle that will return humans to the Moon and then onto Mars and beyond,” Isaacman said. “Every one of these missions will be filled with a number of objectives that are meant to accelerate SpaceX’s vision to make life multi planetary, but you can always count on, just as it is with this mission, we will use every bit of the time available for science and research as well as supporting St. Jude Children’s Research Hospital.”
Isaacman and his crewmates have four main objectives over the course of the five days they will spend on orbit:
- Achieve an Earth-orbit altitude record at 1,400 km (879 mi) apogee
- Conduct the first commercial spacewalk using SpaceX-designed extravehicular activity (EVA) suits
- Perform a technology demonstration of Starlink onboard the Dragon spacecraft
- Conduct about 40 experiments from 20 partner research institutions
Menon said the science data collected during the mission doesn’t end when the crew splashes down off the coast of Florida at the conclusion of their mission.
“When we get back, we will be recovered by the SpaceX recovery vessel and then we will owe some time to science and research and reconnecting with our families,” Menon said.
The mission, set to launch no earlier than 3:38 a.m. EDT (0738 UTC) on Aug. 26, will launch into a 190 x 1,200 km (118 x 746 mi) orbit. The first day on orbit will include raising Dragon’s apogee and passing through the inner regions of the Earth’s Van Allen radiation belt, an area that sees additional charged particles, largely from solar wind.
The region was first discovered in 1958 by astrophysicist James Van Allen and it was most recently encountered by the Apollo 17 astronauts during their return trip from the Moon in 1972.
“We stand to learn quite a bit from that, in terms of human health, science and research. If we get to Mars someday, we’d love to come back and be healthy enough to tell people about it,” Isaacman said. “So, I think that it’s worthwhile to get some exposure in that environment.
“It also informs vehicle architecture because, generally speaking, vehicles don’t like radiation. So that’s why we’re going to stay there for the shortest amount of time that’s necessary to gather the data we want.”
Beyond the human research benefit of this, Bill Gerstenmaier, SpaceX’s vice president of Build and Flight Reliability, said the mission’s dynamic flight profile will also help the company towards certifying their Crew Dragon spacecraft beyond five flights.
“The high altitude will give us exposure to this high-radiation environment, which will test a lot of avionic systems and their ability to recover,” Gerstenmaier said. “We build a lot of auto sequences to take care of that for us, but we’ll see how it really works. We’ll also get a chance to see the laser communication, which I think is a big deal moving forward.”
That laser communication is a demonstration of Starlink internet connectivity onboard a Crew Dragon spacecraft. During her remarks, Gillis showed an image of a Starlink WiFi router nested into the capsule. The Starlink demonstration is set for the fourth day of the mission.
“You might think getting internet might be as easy as just flipping that switch, turning on your internet, but it’s not. We’re talking about a laser sending information to a Starlink satellite that is moving at orbital velocity [more than 17,000 mph], down to Earth, and then back again,” Gillis said. “It’s been an incredible development effort by the SpaceX team and on a personal note, I’ve taken specific interest in this development effort and we have a special message that we will share with the world using this technology.”
First commercial spacewalk
One of the marquee moments of the mission will be when the crew brings the Dragon down to vacuum and performs the first commercial spacewalk. The full operation will take roughly two hours, during which time, both Isaacman and Gillis will egress the vehicle, one at a time, while remaining attached to a roughly 12-foot-long tether.
Gillis said the suit went through quite a bit of modification and iteration to reach the final version that will support the extravehicular activity on the third day of the flight.
“When we first started, we would come in every day for training and pretty much every single day, we’d walk in and there’d be a different suit. It would have a different glove, a different elbow, a different shoulder and there was this constant iteration of suit components with the suit team to test and collect data,” Gillis said. “In parallel with that though, we also had to develop training for that suit.”
Gillis described a special harness that simulated weightlessness while inside the EVA suit, since they didn’t have the ability to constantly put the suit into a pool for testing. She said it also went through thermal vacuum testing to ensure it could stand up to the harsh environment of space.
“We’ve covered everything from life-cycle testing, pressure testing, MMOD testing, extreme hot and colds testing, an entire campaign on ESD and flammability testing. It’s been a really impressive amount of work by the SpaceX team to test this suit for flight,” Gillis said. “As a crew, we’ve spent probably more than 100 hours in this suit at this point… We’re really looking forward to testing this first generation of suit.”
She noted that during the spacewalk, the Dragon spacecraft will be oriented in a way that will shield the crew members from direct sunlight.
Isaacman said that while he and Gillis in turn won’t be free-floating outside of the spacecraft, he said they will fully exit the vehicle during the spacewalk. He said during the operation they will be “well above where the hatch is.”
“We have a hands-free demonstration where it’ll only be our feet engaged in a mobility aid, we’re just not going to be just floating around,” Isaacman said. “It takes a lot of effort to move in the suit when it’s pressurized. What looks like really heavy clothing, becomes super rigid when it’s pressurized.
“So, you want to be very deliberate with your movements. You want to make good use of mobility aids.”
Gerstenmaier, who came to SpaceX following a decades-long career at NASA said it’s been a fun process creating the suits and now being on the cusp of seeing them used in practice. He described the process as leveraging knowledge from NASA and “then we push it a little bit further in other areas,” making sure to share lessons learned along the way.
“This pace of development that we get to do at SpaceX is very much like the pace of development that was required back in the early Apollo days,” Gerstenmaier said. “We’re getting a chance to do that again where we’re really starting to push frontiers with the private sector and learning new things that we would not be able to learn by staying in the risk-free environment here on Earth.
“It’s time to go out. It’s time to explore. It’s time to do these big things and move forward.”
source: spaceflightnow.com