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Aug 26, 2012

BEO-HSF again

Posted by in categories: asteroid/comet impacts, biotech/medical, business, chemistry, counterterrorism, defense, economics, education, engineering, ethics, events, existential risks, finance, futurism, geopolitics, habitats, human trajectories, life extension, lifeboat, media & arts, military, nuclear weapons, physics, policy, space, sustainability, transparency

This essay was posted last year, removed, and is back with small changes. Enjoy.


I became interested in Beyond Earth Orbit- Human Space Flight by way of a college paper I helped my wife research some years ago. Her project for an ethics class was nuclear weapons. I stumbled upon the book “Project Orion, the true story of the atomic spaceship” by George Dyson and was hooked. I had been a science fiction fan in my youth but like most people I thought space operas were only to be realized in the far future. Project Orion changed my worldview. Since then my made up mind has been unmade several times concerning most of the “common knowledge” floating around about space flight in this 21st century. Much of what is generally believed to be true about our space program is made up of recent hearsay used to hype products that further a business plan. When I read these infomercials endlessly repeated as fact I get pretty upset, mostly because exposing these “facts” as false advertising almost always results in vicious attacks. The private space cult fanatics disgust me and I will not apologize for my hard feelings about these people. They mislead, obfuscate, and insult and dogpile anyone who disagrees with their dogma.

It was a slow step by step process but I came to realize the path to the stars is a narrow one. I found the U.S. space effort, described as being on “the flexible path”, to be going nowhere. There is no Flexible Path. The path to colonizing the solar system is narrow indeed due to the laws of physics and materials science. Science fiction movies have conditioned the public to believe such natural laws can be violated and technology that breaks these laws is possible and immanent. This attitude has led to much waste and many tragedies in the past decades and there is soon to come great disappointment over breakthroughs that are far easier said than done. By way of political contributions and backroom deals, the flexible path scheme came into existence as a way of making money for a small group of investors looking to cash in on public ignorance of technology through influence peddling. It is a convoluted and confusing story and perhaps the best way to make the truth clear is to start at the desired end and work backwards.

If the end goal is new worlds for humankind to inhabit, the earliest practical portrayal of a possible new world was in the 1929 work, “The World, The Flesh, and The Devil”, by socialist John Desmond Bernal. I must say I am no socialist (or capitalist), but I am someone who is often unhappy with people at either end of that spectrum. Space is not about politics- it is about survival. More than just surviving- thriving. Human beings need earth-like conditions to thrive and a artificial hollow moon as described by Bernal can provide those conditions.Though the sphere proposed by Bernal does not address artificial gravity, the hollow sphere concept does, if spun, allow for earth gravity on the inner surface at the equator. Hollow spheres in space can provide habitats for thousands, millions, perhaps even tens of billions of people. Space is big, with quite large quantities of rock floating around and plenty of solar energy waiting to be exploited. And tens of thousands of icy comets. Solar energy and low gravity resources in the asteroid belt mean that building on a much larger scale than we do on earth is practical. While we construct thousand foot supertankers and skyscrapers with some difficulty in earth gravity, the same masses of metal and concrete in space can form a shell many miles in diameter with many times less energy expended.

The most interesting fact of all about Bernal spheres is that building them is not any kind of futuristic science fiction undertaking in terms of materials and engineering. The sphere is the strongest shape and the energy to melt and refine ore and the various rocks and ices are available, and so there are no apparent showstoppers. Fill a Bernal sphere with comet water and air and spin and humankind has created a new world to live in. Enclosed worlds capable of traveling for centuries to other star systems when the time comes. While we have the technology, amazingly, to build such hollow moons right now, we lack only a single medical procedure to allow for star travel- revivable cryopreservation. This one key piece of technology, which also breaks no laws of physics, is all that holds the human race back from colonizing the galaxy. This future is not the hyperspace or warp drive or stargate fantasies the public has in mind. Though slowboats do not lend themselves well to screenplays and formula blockbusters, they are exciting to those who understand what is possible in the near future, in just a matter of decades. But before these new worlds can be manufactured, probably near the end of this century, humankind must first establish an infrastructure in deep space to enable that industry.

To live in space is different than just surviving a visit. Missions based on how much radiation and zero G debilitation a human being can survive are certain to fail. Providing earth radiation levels and gravity is certain to succeed. Radiation is the first killer, and lack of gravity as a debilitator is the second made even worse by the first. To set up an infrastructure that will allow colonies and eventually migration requires spaceships and these radiation and hypogravity hazards cannot be avoided. The only guaranteed shield against the heavy nuclei component of cosmic radiation is mass and distance. The only practical spaceship shielding is 14 or more feet of water. The only way to propel this much mass around the solar system is with nuclear energy. Nuclear activities in earth orbit are not acceptable. Lifting thousands and eventually millions of tons of water into earth orbit are also not plausible. This path of reasoning leads to the moon where nuclear activities are permissible and there is water. The only way to get to the moon is with Heavy Lift Vehicles like the Saturn V and the future SLS. The only way to transport fissionables to the moon safely is with Heavy Lift Vehicles. And this is where the private space agenda rears it’s ugly head. HLV’s and anything needing massive governmental resources, such as nuclear energy, are blasphemy to the private space cult. While their dogma preaches that cheap lift can be had with smaller kerosene rockets with a high launch rate, they go on to enable missions beyond earth orbit by way of fuel depots and transfer in space. For a scientifically ignorant public this all makes sense. But it is the kerosene-hydrogen disconnect that exposes the private space flexible path as a business plan to fool taxpayers into subsidizing a Low Earth Orbit space tourism industry for the ultra-rich.

Liquid hydrogen does not store well and is very difficult to transfer. It is difficult on the ground but in space it has never been done because it is such a nightmare. The entire transfer system and receiving tank have to be pre-cooled with liquid helium and a perfect pre-cool is physically impossible. This generates liquid hydrogen boil-off that must be re-liquified- which generates the exo-thermic form of hydrogen- that generates more boil-off. Compounded by space radiation and zero gravity effects, this is all a real mess that no one wants to talk about. Like radiation shielding, it is a topic avoided by private space advocates to the point of hurling insults. Not only is hydrogen hard to handle on the ground and much harder to deal with in space, an engine burning it requires a turbopump ten times more powerful than one for a kerosene engine. Which is why kerosene is hyped by private space as such a wonderful propellent- because both handling hydrogen and using hydrogen engines is much more expensive and cuts into projected profit margins. So why does the orbital fuel depot and transfer concept specify liquid hydrogen? If kerosene is so much better then why bother with liquid hydrogen in orbital fuel depots? Because there is no substitute for hydrogen Earth Departure Stages when it comes to escaping earth’s gravitational field. Using other propellants multiplies the size of these stages several times. Any human missions Beyond Earth Orbit not using liquid hydrogen Earth Departure Stages look like Battlestar Galactica. Because of the Apollo program and every study done on any BEO missions, private space knows they cannot claim otherwise and get away with it. So private space advocates avoid this subject like the plague. Since it is not practical to store or transfer liquid hydrogen in space a direct launch out of orbit, like the Apollo program, is required. The laws of physics have not changed since the 1960’s. Since the inferior lift vehicles advocated in the flexible path are only capable of boosting a few tons at a time out of orbit, Heavy Lift Vehicles become necessary. Thus, there is no substitute for a HLV with hydrogen upper stages. There is no cheap; space flight is inherently expensive.

The resources necessary to build an infrastructure for BEO-HSF are unavailable to private space. HLV’s sending packaged fissionables to the moon are completely out of reach of “entrepreneurs” claiming the flexible path will open the solar system to colonization. In fact, private space claiming they are the future of space exploration is a lie, a deception being used to acquire taxpayer support for space tourism. Forty years of space stations going in endless circles at very high altitude is a dead end. The space tourism industry wants this truth suppressed and portrays LEO stations as the cutting edge of “exploration.” The justification and source of funding for BEO-HSF is impact defense and survival colonies. The DOD is spending vast treasure on useless cold war toys that guarantee huge profits for the defense industry. Just as the new space movement is all about deception, so the the DOD is guilty of neglecting the most vital mission of the U.S. space program; safeguarding the earth and the human race.

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Comments — comments are now closed.

  • JohnHunt on August 26, 2012 5:16 am

    First, what about lunar colonization before Bernal spheres or Mars colonization?

    Second, what about lunar-sourced water shielding and lunar ice-derived propellant to place the shielding into an Aldrin Cycler orbit?

    Thanks.

  • GaryChurch on August 26, 2012 9:18 am

    “The only practical spaceship shielding is 14 or more feet of water. The only way to propel this much mass around the solar system is with nuclear energy. Nuclear activities in earth orbit are not acceptable. Lifting thousands and eventually millions of tons of water into earth orbit are also not plausible. This path of reasoning leads to the moon where nuclear activities are permissible and there is water. The only way to get to the moon is with Heavy Lift Vehicles like the Saturn V and the future SLS. The only way to transport fissionables to the moon safely is with Heavy Lift Vehicles.”

    I am not a believer in chemical propulsion except to get from the Earth to the Moon with an HLV. Once a base is set up near water the last thing we should waste our time on is making rocket fuel; chemical propulsion is useless for interplanetary travel.
    The Aldrin Cycler is not practical IMO. First, Mars is a deep gravity well and for this reason it is actually NOT the place to go to set up a colony. Second, there is little or no protection from radiation. Icy moons in the outer system have low gravity and allow for antarctic type under ice habitats. They are the place to go and set up colonies using small nuclear reactors- and we will not get there with chemical rocket fuel. I would suggest Ceres as the first colony. Hypogravity debilitation can be remedied using “sleeper trains” in circular tunnels to allow small apartment living in 1G for half the day and the other half outside.
    Thanks for the comment John.

  • JohnHunt on August 28, 2012 2:34 am

    @ Gary “The only practical spaceship shielding is 14 or more feet of water”.
    What about hydrogen? It seems as though that would be 1/18th the mass of water per mole. For the same shielding, I’m guessing that it would be about 1/4th the mass of water.

    “The most efficient shielding material is provided by liquid
    hydrogen. It shows the greatest attenuation of high LET
    components with minimal addition of troublesome
    secondary radiations.” — http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20080013522_2008013354.pdf

    Anticipating the obvious response, keeping hydrogen liquid could be accomplished using sun shades and/or solar powered condensors.

    @ Gary “The only way to propel this much mass around the solar system is with nuclear energy”.

    14 feet of water comes to just over 500 tonnes. The mass fraction for ion propulsion from LEO to C3 is about 15% = 75 tonnes. So, if we were to have the 130 mT SLS, then it would take about five launches to assemble enough mass and accelerate it on an interplanetary mission. Could this be an intermediate step?

    Why don’t you find the Aldrin Cycler orbit as practical? What are your reasons?

    Finally, I wasn’t aware that you wanted to start by shooting past the Moon, past Mars, and go for Ceres. Then, if you overcome the hypogravity with sleeper trains my question is, “Is this the earliest, lowest-cost approach to achieving the earliest self-sustaining, minimalist colony”?

  • GaryChurch on August 28, 2012 12:39 pm

    My mistake John, Ceres would be second; I always take the moon as as a given.
    Liquid Hydrogen is really difficult stuff to handle, store, and maintain- this is the key fact everyone seems to overlook. It is really bizarre stuff. Water, on the other hand, is about the most useful and easiest stuff to handle, store and maintain. It can be used for many purposes besides rad shielding. Liquid Hydrogen cannot compare.
    Ion propulsion and basically all forms of reaction propulsion come nowhere near the tens of thousands of seconds of ISP and massive thrust of bomb propulsion. A couple dud bombs will not end the mission like damage to other types of systems will.

    The cycler is.….too slow and only goes to Mars- which I do not think is a good destination.
    Thanks for correcting me on the Moon and Ceres.

  • John Hunt on August 28, 2012 3:26 pm

    OK. Then we are in agreement on the Moon. From my perspective, once we are harvesting enough lunar ice for life support (even before in-space shielding) then we’ve got pretty long-duration stays on the Moon. This will reduce the return-to-Earth flights and crew-replacement flights and so either reduce costs to the program or, better yet, grow the lunar base and hence the initial industrial capacity.

    According to LCROSS results, lunar ice has about as much carbon monoxide as water (5.7% vs 5.6% respectively) and there is also ammonia in the ice. So in the process of processing the ice, you are getting the carbon and nitrogen useful for growing food. Tunnel deep into a lunar hill and you’ve got shielding. So shielding, oxygen, water, and food…that’s a fair ways to long-duration stays. Magnetically extract iron from the regolith, melt it with concentrated solar ice and now you can make the bulky structures. All of this stuff has use in cis-lunar space. So we’re making good progress to where we (e.g. Lifeboat Foundation) need to get in terms of a small, off-Earth self-sustaining colony.

    BUT, I am with you Gary, that, after we are able to produce the shielding necessary for long-duration interplanetary travel, then we need to do exactly that. Once we establish a small self-supporting colony in one place, then we’ll have the skills needed to do it in many other places ever further out into the solar system which is something we need to do. Those would be the ultimate guarantee of the survival of humanity.

    > “The cycler is.…too slow and only goes to Mars”.

    There are a number of cycler orbits with different periods. I don’t know, but it might be possible to establish regular cycler orbits to various asteroids as well. As for “too slow”, instead of the pattern necessarily being frequent launches of single ships, instead it could be launches of numerous crew and supplies only, regularly every two years. It would be akin to occasional transatlantic voyages of large ships carrying large numbers of people. But also, trips could be more frequent if you use different cycler orbits. The beauty of the cycler orbits is that you launch the shielding only once and don’t have to come up with the fuel again and again, forever.

    > Liquid Hydrogen…It is really bizarre stuff.

    Yes, I understand that it just loves to leak. But given the that there is a lot of carbon monoxide in the icy lunar regolith, we could get around that problem by producing methane which is much easier to handle. Boiling points:
    — LH = 20.4 K
    — LOX = 90 K
    — Methane = 112 K

    The delta-v from Lunar orbit to C3 is about 2.3 km/sec. The isps for hydrogen versus methane fuel are:
    — LH = 453 sec
    — Methane = 368 sec
    So the mass fractions of LLO to C3 are about:
    — LH = 40%
    — Methane = 47%
    Although I’m no aerospace engineer, it seems to me as though transporting that much more to LLO when you already have the system in place to transport water for shielding wouldn’t be that difficult.

  • Gary Michael Church on August 28, 2012 4:52 pm

    “after we are able to produce the shielding necessary for long-duration interplanetary travel, then we need to do exactly that. Once we establish a small self-supporting colony in one place, then we’ll have the skills needed to do it in many other places ever further out into the solar system which is something we need to do. Those would be the ultimate guarantee of the survival of humanity.”

    Amen Brother!

    Cyclers to Mars, our closest “habitable” neighbor planet take a couple years- these least energy merry go rounds are not practical simply because of the psychological limits of human beings. 14 feet of water for any large crew compartment, plus a tether system to generate artificial gravity works out to Battlestar Galactica size craft.

    The faster you get there and back means a smaller crew compartment- means a faster ship. These least energy flight plans will not work going to the outer solar system destinations. Which is why chemical, nuclear thermal, and low thrust forms of propulsion are all worthless.
    It is all about the bombs.
    Thanks for the reply John. Please check out my new essay.
    Regards, Gary

  • JohnHunt on August 31, 2012 3:25 pm

    There aching the outer solar system can be done in steps when there are planetary conjunctions. For example, the asteroid belt is just beyond Mars. So, establish a base on Phobos or something and then, launch from there to Vesta. Here are the astronomical steps:

    To Mars — .5
    To Vesta — .86
    To Ceres — .4
    To Jupiter — 2.6

    Plus, Zubrin makes the point that modern astronauts would be much less isolated from home than has been successfully endured in many situations such as multi- year shipping expeditions. I think that the key is having large, even unshielded volumes to go to periodically.

  • GaryChurch on September 2, 2012 2:40 pm

    ” I think that the key is having large, even unshielded volumes to go to periodically.”

    I think a better solution is nuclear propulsion since traveling to the outer system moons- even out to Neptune- simply cannot be done without it. Wasting time on chemical propulsion is just that; wasting time.