SpaceX is about to send four people on a wild — and risky — mission into the radiation belts. 

1) The International Space Station orbits about 250 miles (400 kilometers) above Earth. 2) The Hubble Space Telescope, which NASA astronauts have conducted spacewalks to repair, orbits about 320 miles (515 kilometers) high. 3) The innermost of two bands that make up the Van Allen radiation belts begins at about 600 miles (1,000 kilometers). 4) The Polaris Dawn mission will reach a maximum altitude of 870 miles (1,400 kilometers) before lowering its apogee for the spacewalk. CNN/Getty Images/Space X/Adobe Stock

On Monday, Isaacman and three crewmates — including his close friend and former Air Force pilot, Scott “Kidd” Poteet, as well as two SpaceX engineers, Anna Menon and Sarah Gillis — will arrive at Kennedy Space Center in Florida to prepare for the launch of a far grander, more dangerous, and experimental trip to space. The mission, called Polaris Dawn, is slated to take off no earlier than 3:30 a.m. ET on August 26.

Isaacman, Menon, Gillis and Poteet will spend five days aboard a SpaceX Crew Dragon capsule that will soar to altitudes higher than any human has traveled since NASA’s Apollo program ended in the 1970s. Their orbital path will extend high enough to plunge the vehicle and crew into a radiation belt, adding another element of peril to the already treacherous experience of spaceflight.

This crew of private citizens will also open the hatch of their spacecraft and expose themselves to the vacuum of space, marking the first time such a feat has been attempted by non-government astronauts. During this endeavor, the astronauts will be protected solely by brand-new Extra-Vehicular Activity (EVA) suits, which SpaceX designed and developed in just two and a half years.

First announced in 2022, Polaris Dawn is the first of three testing and development missions under the Polaris Program that Isaacman said he will jointly execute and fund alongside SpaceX. He declined to say how much this mission cost. The end goal of the Polaris Program is to take the first steps toward validating technology that SpaceX will one day need if it carries humans deeper into the cosmos — including spacesuits, EVA and life-support technologies.

After launch, the Polaris Dawn crew will travel into an oval-shaped orbit that extends as high as 870 miles (1,400 kilometers) from Earth. That’s well into the inner band of Earth’s Van Allen radiation belts, which begin at around 600 miles (1,000 kilometers) in altitude. The belts are areas where concentrations of high-energy particles that come from the sun and interact with Earth’s atmosphere are trapped, creating two dangerous bands of radiation, according to NASA.

Almost immediately after reaching space, the Polaris Dawn crew will begin a “pre-breathe” process to prepare for the spacewalk. It’s akin to what scuba divers do to avoid decompression sickness, otherwise known as “the bends.” The crewmates must purge nitrogen from their blood so that when the Dragon capsule is depressurized and exposed to the vacuum of space, the gas doesn’t form bubbles in their bloodstream — a potentially lethal condition. “We don’t have an airlock on this mission,” Gillis told CNN, referring to the areas on board the International Space Station (ISS) that serve as special decompression chambers for astronauts heading out for a spacewalk. Polaris Dawn will instead take “a really novel and different approach” to the pre-breathing process that involves “slowly decreasing cabin pressure and raising oxygen concentration.”

Unlike any pre-breathe attempted on the International Space Station, the process will take roughly 45 hours — nearly two days, said Gillis, who works as a lead space operations engineer at SpaceX and trained the Inspiration4 crew for their mission.

Finally, to kick off their third day in space, the Polaris Dawn crew will open the Crew Dragon’s hatch as they’re about 435 miles (700 kilometers) above Earth. All four of the crew members and the entirety of the spacecraft’s interior will be exposed to the expansive void. Only Isaacman and Gillis will actually exit the spacecraft, however, tethered by a couple of umbilicals. From beginning to end, the Polaris Dawn mission exposes the crew to more risk than other orbital space tourism missions have, including SpaceX missions that have carried paying customers to the International Space Station, which orbits about 250 miles (400 kilometers) above Earth.

https://www.cnn.com/2024/08/19/science/spacex-polaris-dawn-jared-isaacman-spacewalk/index.html

Comment: The launch will look almost mundane considering all the successful launches SpaceX has accomplished, but the spacewalk should be quite interesting. I sure as hell hope that’s televised in real time. It reminds me of the first Gemini spacewalk. That one was done with an umbilical cord, too.

TTG

https://appel.nasa.gov/2015/06/24/this-month-in-nasa-history-gemini-iv-took-critical-steps-in-space

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15 Responses to SpaceX is about to send four people on a wild — and risky — mission into the radiation belts. 

  1. ked says:

    performing experiments on humans in outer space – interesting indeed. I think the humans will be ok. I think the risk is in the (no doubt well-devised & tested) support systems for those tests. the high altitude oval orbit, new space suits & umbilicals, the non air-locked capsule, the 45 hrs bends management program… a lot to pack & unpack. godspeed & good fortune to them.

    • TTG says:

      ked,

      I don’t know of any capsule that had an airlock, unless you count the space shuttles. All Gemini, Apollo and Soyuz space walks required depressurizing the crew cabin.

  2. Lars says:

    There is a lot of excitement locally about this mission. It is certainly “edgy”. I hope the weather will cooperate. We are heading into the top of the hurricane season. I hope all goes well.

  3. leith says:

    Got to wonder how much $$$ millionaire Jared Isaacman pays Musk for this trip. I hope he at least donates another one or two hundred mil to St Judes Children’s hospital like he did on his last Space-X flight.

  4. “This isn’t your grandfather’s NASA anymore.”
    https://sonar21.com/this-isnt-your-grandfathers-nasa-anymore/

    “The current NASA is significantly different from the organization in your grandfather’s era.
    It now prioritizes diversity, equity, and inclusion (DEI)
    and is no longer at the forefront of innovation and exploration.
    Instead, billionaires Elon Musk’s SpaceX and Jeff Bezos’s Blue Origin have displaced NASA in space exploration.
    Some believe that the focus on DEI is negatively impacting the culture. “

  5. Lars says:

    I have a neighbor, a very nice lady, who only will admit that she is involved with “skunk works”. She is working with some of the major defense contractors, all who have offices in the area. Through other means, I found out that the effort she heads have a budget of $44B and it is suspected that they are designing and later building the next generation spy plane. As far as the original space people, many who I have met, DEI was definitely involved. They mostly were a bunch of characters who got tired of the military, especially the Navy and quite a few were what we today would refer to as “hillbillies”. It is actually strange that they could make as much progress as they did. Of course, today the enterprise would not be able to accommodate their originality. One of them, who ended up as deputy director of the Space Center once, after pushing the button and nothing happened, drove out to the rocket and smacked it with a hammer. Which fixed it.

    • Fred says:

      Lars,

      Everybody hits rockets with hammers now. It’s not like we have Arthur Rudolph designing them any more. Kudos to diversity skunk lady and her billions. You would think that after all the prior billions the skunk people would have been able to do what Elon did rather than just fund Boeing, Lockheed, and pensions.

      • TTG says:

        Fred,

        SpaceX is also a big government contractor receiving billions in government funding. Some call the billions subsidies, but I think payment for services is a better term for most of the billions, although SpaceX R&D is also largely funded by the government.

        • Fred says:

          TTG,

          SpaceX works at a fraction of the cost of the rest. The anonymous anecdote people, well they make nice feel good stories of dubious value.

    • leith says:

      Lars –

      Love the hammer story. A good rap can fix most anything. Reminds me of the old aerospace engineers from Douglas Aircraft in the late 40’s early 50’s launching captured V2 rockets at White Sands. I heard the story 40 years later. In the event of a failure of the rocket engine to fire they would take a jeep out to the test stand. Leaving the jeep idling they would light off the rocket engine’s ethanol fuel mix with a lit kerosene-soaked broom. And immediately take off at 90 mph to get behind the observation bunker. Soldiers from the Army Ordance Office dubbed them the Douglas Daredevils.

      I would bet that von Braun or his techs probably had to do something similar at Peenemunde.

  6. Lars says:

    It will take some time to get this mission off the ground. SpaceX has been grounded by the FAA, due to the returning rocket catching fire and falling over on the drone ship the other morning. From the video it looks like fuel splashed out of the rocket onto the hot landing zone. It was the 23rd time for that rocket and they may have to look at how long they can reuse them.

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