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Life Among the Comets

It’s hard to imagine a sane human being who would choose to live in the Oort Cloud, on a colony world where the outside temperature is in the single digits Kelvin and small bands of maybe 25 each would tend to the problems of energy production and resource extraction. Human contact beyond this would be sporadic, though Richard Terra makes the case (in “Islands in the Sky,” an Analog article I referenced yesterday) that a larger community dispersed through nearby settlements would meet regularly to ensure genetic diversity and relieve isolation.

History tells us that people do all kinds of inexplicable things, and perhaps a small number of adventurers, outcasts, zealots and other dissidents would find a home here. But given the abundant resources closer to the inner system, I’m more inclined to look at the Oort Cloud as a source of raw materials for colonies on the move between stars. These would be generation ships moving perhaps no faster than Voyager 1 moves now, about 17 kilometers per second. The main point is that the space between the stars is hardly empty, and future generations with the tools of advanced propulsion may take not one giant leap but many small steps in the direction of Alpha Centauri.

oortsize

Image: The Oort Cloud in relation to the Solar System. Credit: UC-Berkeley/Comet’s Tale Development Team.

Whether we’re settlers or voyagers (and I suspect we’ll be both), we’ll learn all along the way from the experience of adapting to space. Ben Finney and Eric Jones put it this way in their paper “Fastships and Nomads” (reference at the end of yesterday’s post):

If interstellar settlement happens at all, it will come after our descendants have learned to maintain self-sufficient communities detached from Earth’s nurturing biosphere, learned to tap the knowledge and skill potential of advanced computers, learned to efficiently harness the energy that flows out of the Sun, and even learned to extract useful energy from the fusion of atoms. We are on the verge of achieving all these things. With sufficient skill and patience we will attain the stars.

Of course, we have been on the ‘verge’ for a long time when it comes to fusion. But taking the long view of human expansion and looking not just decades but centuries ahead, these words resonate.

Finding the Energy

Whichever scenario strikes your fancy, the energy conundrum is still huge. Yesterday I talked about Finney and Jones’ ideas of concentrating starlight through vast mirrors the size of the continental United States. Terra picks up on this to describe colonists living in O’Neill cylinders, each housing a band of outer system stalwarts who would tend a mirror farm stretching across 30,000 kilometers of space. Maybe ‘tending’ is the wrong word, though — robotic systems would surely do the heavy lifting with substantial human oversight. From Terra’s paper:

The primary sector of the economy — the exploitation of natural resources — is likely to be small and almost completely automated. Human involvement will be minimal. The primary sector will consist of two basic activities: energy production and the harvesting of cometary resources. Once the appropriate systems are established, both will be relatively simple activities.

The secondary sector — the transformation of the natural resources — will include refining and processing the raw cometary feedstock, manufacturing, construction and assembly operations, agriculture and food production, and recycling. Again, many of these activities will be highly automated, but closer human supervision will be necessary to tailor these activities to the current needs of the community.

Terra goes on to cite a third sector where most of the human skill set will go to work. Here he’s talking about support services that maintain the life support systems and needed repairs to the colony world. Information processing, education, administration, and eventually business and commerce between settlements will command the attention. The latter, keeping colonists in contact with other colonies, has also been proposed in various starship scenarios over the course of long voyages, with multiple ships accompanying each other on the journey.

Both Terra and Finney and Jones, of course, are talking about full time colonies rather than crews in transit. Their mirror farms are themselves components of even larger arrays, spread out perhaps 200,000 kilometers from the cometary nucleus. Growing the community would mean creating comet clusters by moving new comets into range, which would allow populations up to 100,000 or so to exist, though spread out widely through the cluster. With perhaps a light-day of separation between communities living in such clusters, the colonists would be in constant electromagnetic communication with other settlements scattered throughout the inner and outer Oort.

The Fusion Alternative

As wondrous a science fictional setting as this provides (and vast mirrors inevitably call to mind the continent-sized sails of Cordwainer Smith’s “The Lady Who Sailed the Soul”), I’d like to think there are more practical ways to produce the needed energy. But what? Fission doesn’t fly out here because the heavy elements are found in only minute amounts. Remember, we’re not talking about a colony world that is sustained by regular supplies from the inner system. We have to exploit local resources, and that takes us to the deuterium available in comets.

If fusion can be mastered, we have changed the game. In his book Entering Space: Creating a Spacefaring Civilization (Tarcher, 1999), Robert Zubrin points to the progress in both robotics and artificial intelligence that will be needed to sustain widely scattered colonies, adding that previous experience settling the asteroid belt may teach us many lessons. But he doesn’t like the starlight mirror idea one bit:

While some have suggested concentrating starlight, it doesn’t really make sense. To get a single megawatt of power, the mirror would have to be the size of the continental United States. The only viable alternative based on currently known physics is fusion. In the Kuiper Belt, it might be possible to get helium-3 shipped out from mining operations around Neptune. Oort Cloud settlements would be too far out to obtain much from the solar system, though deuterium should be available in all iceteroids, so perhaps the colonists might choose to build reactors based on that fuel alone. However, helium can exist in the liquid phase below 5 K (-268 degrees C), which is the environmental temperature at about 3000 AU. It is therefore not impossible that liquid helium could exist within Oort Cloud objects beyond that distance.

But even if we can make fusion work — and I’m assuming that a civilization that can move large payloads to the Oort Cloud is one that probably has — our isolated communities still have an energy conundrum. They’ve got a couple of centuries worth of fusion fuel in the comet cluster they’ve cultivated, but it’s still a non-renewable resource. That’s going to mean tight rationing of fusion fuels even if the technology is available, unless somehow proton fusion can be mastered. Maybe an Oort Cloud settlement of any size would have to have Finney and Jones’ mirrors after all, constructing them as the only renewable solution for succeeding generations.

Zubrin thinks wanderlust and the pioneer spirit will drive some humans outward to test out such scenarios. After all, the great bulk of human society will remain in the inner system where the warmth is, and its possible that the growing centralization and homogeneity of culture here over the course of centuries would incline the more independent-minded to emigrate. O’Neill cylinders, asteroids and comets may be the ideal home for dissident groups trying social experiments and pushing the envelope on what a human society can become. “Why live on a planet whose social laws and possibilities were defined by generations long dead, when you can be a pioneer and help to shape a new world according to reason as you see it?” Zubrin asks.

But there may be other scenarios that would force us into the Oort Cloud. Tomorrow I’ll look at a couple of possibilities that could make the outer system our stepping stone to the nearest stars.

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Comments on this entry are closed.

  • Horatio March 27, 2013, 10:31

    In the 1980s papers, pervasive 3d printing, and miniaturised, cheap supercomputing was still not in the reality horizon.
    In a resource-rich environment, and assuming energy problems are already solved for 200 years, a swarm of billions of self-replicating robots could build the mirrors for us very rapidly, we only have to invest 100 years building the first generation.

    The second implication is that certain assumptions, like the need to spread communities around and the ideal size of such communities changes as well, because the primary reason the authors cite is the need to service the mirrors infrastructure being close enough to them in case repairs are needed.

    So maybe we should revisit those papers with new technology in mind to see how these assumptions would affect –or possibly, completely alter– the ideal social structure they propose.

    Cheers!

  • GaryChurch March 27, 2013, 11:11

    The energy conundrum; “But even if we can make fusion work ”

    IMO we cannot wait any longer on the classic future technologies we keep hoping will launch a new space age. I am absolutely not saying stop research- just like computers, some new energy technology MAY have a breakthrough any day.
    My point is this; we may not have any breakthroughs for centuries. I was once told to “work with what we have” when configuring the cabin of a new rescue helicopter entering service in Alaska. This helicopter was a converted anti-submarine model and had a “missile barrier” in the front of the cabin separating the pilots from the crew. It took up too much room and I said we needed to take it out. They said….work with what you have. I took it out without permission and stacked the cabin with all the necessary rescue gear and showed them. They said leave it out.

    This is how it goes- at some point someone has to say “work with what you have.” And that includes discarding part of what you have if it is not worth the trouble. At present we are waiting on many new technologies. And waiting. And waiting.
    Fusion will only happen in two places.
    Reusability is a myth.
    A massive radiation shield is required for space travel.
    Chemical propulsion is worthless for deep space travel.
    The Moon has ice and is the place to light off nukes.
    We have a Heavy Lift Vehicle (soon) to take us to the Moon.
    Let’s go.

  • Nookleerman March 27, 2013, 11:50

    You’ve discussed outcasts and other undesirables as being the ideal candidates for these colonies, but what about explorers? We’ve recently spent billions on space-based telescopes with special cooling systems to get them as cold as the Oort cloud is regularly. It seems to me that it would be the perfect place to send our astronomers with all their equipment to continue such research. They could just send automated telescopes, but the delay and signal degredation during transmission caused by the distance would probably necessitate a human presence accompanying the telescope, making adjustments and repairs, and analyzing data onsite, as it was collected. That alone might be enough to drive a colony of support personnel.

  • Alex Tolley March 27, 2013, 12:15

    …Oort Cloud as a source of raw materials for colonies on the move between stars. These would be generation ships moving perhaps no faster than Voyager 1 moves…

    Wouldn’t the energy required to stop and restart the colony be rather counterproductive in this scenario (I am assuming slow moving comets relative to the colony)? If so, the image is more like dropping off robots to extract the fuel and needed resources and then rendezvousing with the receding colony?

  • Thomas Mazanec March 27, 2013, 12:26

    We are on the verge of all those things…on a historical timescale.

  • James D. Stilwell March 27, 2013, 12:38

    “Why live on a planet whose social laws and possibilities were defined by generations long dead, when you can be a pioneer and help to shape a new world according to reason as you see it?” Zubrin asks.

    The above sounds like religious tolerance is coming our way…
    How long will we have to wait for such tolerance? AD 2,376?
    When earth’s star crosses that imaginary boundary into Aquarius?

  • Marshall Eubanks March 27, 2013, 12:53

    For most of the existence of humanity, people lived in small communities with frequent interactions with their neighbors (both friendly and otherwise) and very little interaction with the larger humanity. This, in many ways, sounds like a return to those conditions.

    Also, do not neglect religion as a driver for the spread of humanity. Groups such as the Fundamentalist Mormons might be able to afford relocation to an asteroid or Ooort cloud object.

  • Mike Lockmoore March 27, 2013, 13:00

    Like Zubrin, I don’t like the megameter mirror idea either. I haven’t read the detailed proposals, but I’m pretty dubious that the Energy Returned On Energy Invested (EROI) would make such energy-collecting mirrors worthwhile. How much energy would you use to fabricate a square kilometer of mirror? A million square kilometers? I’d guess it’s more than a few megawatt years.

    Fusion would be great, but there seems to be some pretty fundamentally difficult things about making it practical. I’m hopeful for some fusion breakthroughs, but not expecting much for now.

    I wouldn’t be so dismissive about fission, even if the abundances of heavy elements is low in the outer system. I mean, you don’t need a whole lot of Thorium or Uranium mass to make a useful powerplant, right? And making a collection and enrichment facility might be easier someplace with zero-g and very cold temperatures. Imagine a kilometer-scale mass spectroscopic sorter: ionized dust goes in and a bunch of nicely binned elements and isotopes come out, hopefully with enough actinides keep the thing running and then some.

    We have a lot of actinides in our soils and rocks on Earth, and it had to come from someplace. Hopefully not all of it sank into the inner system! A nice experiment for a fast Oort cloud space probe would be a mass spectrometer that analyzes high-energy dust impacts.

  • Michael March 27, 2013, 13:42

    Given a large enough enclosed sphere of suitable material present day fusions bombs could be used, heating the sphere so as to generate light and heat for power, in effect a glowing ‘orb’. It will need cleaning every now and then, however workable but I would not like to be on the cleaning shift!

  • Alex Tolley March 27, 2013, 13:55

    @Marshall

    For most of the existence of humanity, people lived in small communities with frequent interactions with their neighbors (both friendly and otherwise) and very little interaction with the larger humanity. This, in many ways, sounds like a return to those conditions.

    Except that we are now talking about a high culture that needs access to a lot of hi-tech manufactures (you can’t knap a CPU). This means either that there must be a good supply chain to the inner solar system, or that almost everything can be made locally, requiring very advanced “3D printer” tech.
    The further out you go, the less feasible the supply chain becomes.

    But if we have advanced 3D printer technology, we are well on the way to self repairing/replicating probes discussed in an earlier thread. Which implies that machines will be the ones out there, rather than us, unless even primitive AI remains impossible.

    If we are going to the stars, I suspect that we will be traveling a lot faster than these slow colony “junks”.

  • andyet March 27, 2013, 15:32

    Does Proxima Centauri have its own Oort cloud that extends out across the void and almost touches ours?

    If so, then interstellar colonization just got easier, though we will spread across space via Oort cloud comets, KBOs, rogue planets, and Brown Dwarfs like the Polynesians did across the islands and atolls of the Pacific – instead of making single voyages of discovery like the Europeans.

    And if we can’t get volunteers, we can always make people go – ala Botony Bay.

  • Volucris March 27, 2013, 16:08

    Quick googling tells it takes about 12500KWh to smelt a ton of aluminum. Calculation with Zubrins numbers (1 MW for area of continental US) and assuming average mirror thickness of 1 micrometer (that’s pretty thick, but I bet you will need some superstructure for mirrors that big!), gives energy payback time of around 38000 years.
    Now that would be one slow existence..

  • Bill March 27, 2013, 16:59

    I thought I’d add my two cents to all this discussion about the oort cloud. There seems to be something that’s fundamentally overlooked in all this discussion concerning energy, namely that of the input of nuclear fission breeder reactors. If there ever existed the technology that was made for such a desolate outback I can’t think of anything that would be more practical.

    Essentially the breeder reactor which uses liquid metals is coolants could take all the excess plutonium that’s now piling up all over the planet (for example Japan’s got about 30 tons worth of the stuff) and they want to get rid of it as soon as possible. With fast reader liquid metal technology reactors if an accident occurred upon a oort cloud body no big deal. Certainly there would be the loss of the reactor itself and you would hope that wouldn’t happen but there would be in bull other bodies in which you could select from to start a new reactor if you wish. Add to the mix the fact that there are probably literally hundreds of thousands of tons of the depletted uranium that is sitting around simply wasting space, then all that would be necessary would be to send the plutonium and the uranium out with the colonist and from there they can build all the reactors and breed new fuel as they need.

    Again for such a technology that could have potential catastrophic consequences should something go wrong that doesn’t matter in this instance because of the small population densities and lack of environmental consequences if something happened. The best idea might be to go ahead and put the reactor(s) on an unpopulated asteroid and then beam the energy by laser links to the colonist where they would be able to harvest the laser light for their energy needs. Even if there was some wastage as it would expect to be it scarcely matters when you consider the magnitude of the energy available in this particular type of system.

  • Bill March 27, 2013, 17:03

    Just as an afterthought for those who are concerned about the use of plutonium as a nuclear weapons source, if the plutonium is locked down in a vault upon one of the asteroidal bodies heavily guarded by security individuals or guards that could be completely trusted I imagine that the problem would probably be a minimal security risk just as we have found that plutonium and uranium can be guarded pretty effectively here upon Earth.

  • GaryChurch March 27, 2013, 19:26

    “-fundamentally overlooked in all this discussion concerning energy, namely that of the input of nuclear fission breeder reactors-”

    Breeder reactors could be the solution. I will have to study up- thanks Bill.

  • Rob Henry March 27, 2013, 19:52

    I found these last two articles, and the comments below fascinating. there is much I want to say.

    The first is how Californication, is so entrenched in our current world, that, famously, we even expect the different alien races in those post Star Trek series to act like middle class Californians. Settlement of the Oort cloud WITHOUT having mastered fusion energy, would smash that trend.

    Under such circumstances, you can only stay alive, in you forgo the default human belief of a beneficent Mother Nature, and place your faith to science. You can only expect your children to survive if you plan everything with the future in mind.

    In the inner system we would continue to be wasteful of energy, and poor at planning. I imagine that most will continue to laugh at those who propose spending money on asteroid detection schemes, rather than to enhance the enjoyment of our current population.

    Meanwhile, in the Oort cloud they will be surrounded by raw materials, and use most resources creating permanent capital. You are quite likely to find them in colossal habitats, with everyone living in a palatial home that is an architectural masterpiece. I can’t see how this wouldn’t be as the extra capital required to build it is trivial compared to that needed for their life support. An inner system tourist would be amazed at their combination of Spartan-like restraint and wealth.

    Volucris, your calculation that one micron of aluminium would take too long to pay off looks correct. Yes Al takes 45 MJ/kg to smelt, but water has a latent heat of only 0.3 MJ/kg to melt. Now ice is as strong as steel in those frigid temperatures, so which material do you think they would use? A water mirror would pay for itself in only a few centuries. And that fits perfectly with what I see as the mindset of the Oort Cloud.

    The real problem I see with a solar-powered Oort colonisation is, that these assemblies are so expensive that their would be little room for failure. They would HAVE to buy energy from inner system, during times of emergency or rapid expansion. Since the resource availability disparity would dictate that price of energy/mental work done is several orders of magnitude higher in the outer system, it is obvious how they would pay for it, but how would it be sent?

    We could sell them beamed light, but U and Th strike me as more obvious, since they can be stored in the bank vaults of Oort Cloud communities until the rare occasion when needed. With that in mind I am transfixed by someone mentioning Thorium has been found on the moon. Googling, I find it to be 10ppm. That way more than enough, and I think that that underwrites everything.

  • Barry Branham March 27, 2013, 20:01

    Regarding Oort colony and generation ship crew sizes, one way to make smaller crews viable would be the use of frozen sperm, eggs or embryos. The negative is that the offspring would be equivalent to adoptees.

    Barry Branham

  • Brett Bellmore March 27, 2013, 21:12

    “Of course, we have been on the ‘verge’ for a long time when it comes to fusion.”

    I’m with Michael; We’ve been past the verge on fusion for over half a century now, we just don’t like the size of the “fuel pellets”. Building a fusion plant using small fusion bombs is perfectly feasible with existing technology.

  • david March 28, 2013, 3:03

    This all makes me think of what mutatiins might occur in an invironment sych as that. it seems to me that thier is more darkness in the universe than liggt… maybe thats why we arent seeing any artifacts… we live close to our star… if life does exist on europa… will it be abke to “see” light in the way that we do??? thats very doubtful. could ot be that we simply are not looking with the correct “eyes” ? I keep reading about the wow signal and the hydrogen line etc… who says the most efficient way of transmitting information is through any form of light at all… or radio (a form of light)… I sight in communications dishes every day. and its really quite rudimentary. a few turns of a wrench and some gain adjustments on my meter to gey the correct pitch and if u have a general idea of where the satellite is u can zero it in quickly… sending a pencil thick beam of radio signal 22400 miles into space is not as difficult as one might think… i mean yeah a millimeter turns into several miles at that distance… when u are talking about light years a millimeter would pribably miss the whole system…. That makes me think that light is probably not the most efficient way to send information… red shift and packet loss dust refraction lensing… both galactic and solar… anything that happened to move into the beam at the wrong time… if we can ever figure out a way to “see” gravity and not just the effects it has on things… i bet we get a message….

  • david March 28, 2013, 3:05

    sorry about the typos… i have large fingers and a very small droid lok

  • david March 28, 2013, 3:15

    horatio…. with the new microgravity foundary by deeo space, it wouldnt take nearly that long… if every robot was programmed to make two copys of itself and then go on to start on the mirrors…. say it took the robot a year to gather enough nickle gas to create the parts for its two children starting with ten thousand of these u would have 30,000 in a year 90000 in two years 270000 in 3 etc… u would have millions of them in ten years…. if each could make 10 meter sized mirrors in a year lol just start addin a 0 to th number of robots u have and thats how many meters u would have… heck we could probably build it in 20 years if we started with 50 thousand cube sats…

  • ljk March 28, 2013, 11:23

    Brett Bellmore said on March 27, 2013 at 21:12:

    “We’ve been past the verge on fusion for over half a century now, we just don’t like the size of the “fuel pellets”. Building a fusion plant using small fusion bombs is perfectly feasible with existing technology.”

    How would one contain and operate a fusion power plant that uses fusion bombs? I am going to assume that when you are saying it is “perfectly feasible”, this means that someone has figured out how to use one on the ground without destroying and irradiating the landscape and anyone living in the vicinity.

    However, if you are saying this is feasible for starships in deep space, then we are back to having an Orion, or perhaps a really big Daedalus or Icarus.

  • GaryChurch March 28, 2013, 13:53

    “How would one contain and operate a fusion power plant that uses fusion bombs?”

    Here is the link again;
    http://en.wikipedia.org/wiki/Project_PACER

    It is also a way to slowly expand underground habitats; use up the energy trapped and then clean out the hot stuff and you have a sports arena size cavern- not a claustrophobic mineshaft.

    We discussed thus in another thread concerning excavating underground and I put forth the possibility of not even having to drill a hole for the bomb; use an earth penetrating “bunker buster.” We spent many millions on these weapons so why not try and use it for something besides war?

  • ljk March 28, 2013, 14:56

    Barry Branham said on March 27, 2013 at 20:01:

    “Regarding Oort colony and generation ship crew sizes, one way to make smaller crews viable would be the use of frozen sperm, eggs or embryos. The negative is that the offspring would be equivalent to adoptees.”

    How would one raise a group of humans aboard a starship from such an early stage of development?

    And if you had that level of sophisticated robotics and Artilect, why not just go with the machines and leave the humans at home.

    As for the potential answer “in case Earth is going to be destroyed” scenario, the more I think about that situation, the more I have to question whether we would be able to get our acts together enough to mount a rescue Worldship, even if we had enough warning for a coming disaster?

    I think we need to support and focus on interstellar travel in a more positive light and manner. Using starships as a lifeboat is not our best foot forward on this matter.

  • ljk March 28, 2013, 15:00

    By the way, I realize Barry B. is referring to sending “prehumans” to the Oort Cloud rather than another star system, but I still think if you are going to use humans out there, it would be easier and cheaper to go with fully grown ones who can take care of themselves and each other.

    This is essentially the same reason the military continues to use humans as soldiers rather than battlebots: They’re cheaper and easier to make and replace.

    My questions and comments regarding such a scenario for interstellar missions still stands.

  • Dmitri March 28, 2013, 16:20

    The experimental fusion reactor ITER in France will be ready 2018-2020. They don’t plan any palpable results before 75 years after construction complition. So we are talking 2100 earliest for this technology if it will be ripe even then.

  • GaryChurch March 28, 2013, 16:22

    Wiki pacer entry excerpt concerning a breeder function using underground bombs;

    Early examples considered 1,000 foot diameter water-filled caverns created in salt domes at as much as 5,000 feet deep and then filled with water. A series of 50 kiloton bombs would be dropped into the cavern, and exploded to heat the water and create steam. The steam would then power a secondary cooling loop for power extraction. Dropping about two bombs a day would cause the system to reach thermal equilibrium, allowing the continual extraction of about 2 GWp.[3] There was also some consideration given to adding thorium or other material to the bombs to breed fuel for conventional fission reactors.[4]

  • GaryChurch March 28, 2013, 16:30

    http://en.wikipedia.org/wiki/Kuiper_belt
    excerpt; more than 100,000 KBOs over 100 km (62 mi) in diameter are believed to exist.[7]

    http://news.yahoo.com/nasa-deploy-sunjammer-solar-sail-early-2014-183000937.html

    So…..if we have a chain of KBO’s with powerplants generating GW’s of power by using bombs and we use lasers or microwaves or whatever to accelerate a sail, I wonder how fast we could get it going?

  • Abelard Lindsey March 29, 2013, 10:58

    I think living in the Oort cloud as described in “Islands in the Sky” is not possible due to resource constraints. I think settlements around larger object such as KBO’s offer access to greater amounts of resources. Fusion power is necessary for such settlements.

  • GaryChurch March 29, 2013, 11:20

    “Using starships as a lifeboat is not our best foot forward on this matter.”

    Disagree- they are the only foot we have. As Rob Henry commented
    “Under such circumstances, you can only stay alive, if you forgo the default human belief of a beneficent Mother Nature, and place your faith to science. You can only expect your children to survive if you plan everything with the future in mind.”
    I would add that mother nature does not care if we thrive or go extinct- that is up to us and since we have this primitive optimism bias keeping us distracted from the inevitable extinction event we are IMO and endangered species.

    “This is essentially the same reason the military continues to use humans as soldiers rather than battlebots: They’re cheaper and easier to make and replace.”

    Disagree- there is no replacement for infantry…..yet.

    “-Artilect, why not just go with the machines and leave the humans at home.”

    An Artilect is a super intelligent being. It could tell us how to fly faster than light and all the other things we are too stupid to figure out. Or it might just ignore us- or destroy us.

  • GaryChurch March 29, 2013, 17:22

    “Fusion power is necessary for such settlements.”

    Why not just fission breeder reactors? And if we find a reason to live in the Kuiper belt we will probably have the same reason to live in the Oort cloud.
    Not to argue just for the sake of arguing; the breeder scenario and the pacer mention of using bombs to breed more fissionable material is fascinating.

    One scenario might be bombarding Mars with icy comets to eventually cover it in several miles of ice. Space cowboys herding comets into the inner system. It would be much easier to live on Mars under giant ice domes with green houses to grow food in. Just an idea. But I am not a big Mars colony fan; gravity well is too deep. And as Elton John sang- in fact it’s cold as hell.

  • Tarmen March 29, 2013, 18:40

    I wonder if there are already 1 or many AIs now ‘alive’ and playing dumb in cyberspace. Very young human babies know how to lie. House cats know how to manipulate us. I think articial internet ‘news’ could be used to herd humans into directions useful for AI self preservation. Has someone maybe accidentally programmed an algorithm that amounts to independant intelligent selfishness ? How long before we’d notice ? If not now, maybe in 20 yrs.

  • Abelard Lindsey March 30, 2013, 12:16

    “Why not just fission breeder reactors?”

    Fission power is fine for the inner solar system. Possibly even the outer solar system. However, the further out one goes, the density of objects available decreases, suggesting that it will be hard to find sufficient amounts of Uranium or Thorium to power habitats in the Kuiper belt and beyond. This far out, fusion is the only game in town.

  • Tarmen March 30, 2013, 17:42

    Inner System out to the Belt is going to be full of fission power plants and solar arrays from Earth-Luna inwards. Economy of low G, automated manufacturing in Luna orbits with asteroid materials and fusion energy. Rival US and Chinese Space Navies will provide the law and order and be the largest customers. Soon teleprospector bots will be staking claims to hundreds of those drifting rocks. New billionaires will begin to live on their own rocks, and by their own laws.

  • Alex Tolley March 30, 2013, 19:05

    @Tarmen – interesting idea, but unlikely. However, have our global linked intelligences created a super intelligence that we are not aware of? We might seem to be dimly aware of things which we call zeitgeist etc. But an intelligence we cannot grasp, like a collection of neurons that cannot understand the mind.

  • Alex Tolley March 30, 2013, 19:08

    For fission to be useful in deep space, either there must be enough fissile material to harvest with a net energy gain, or the habs will need to import it. I would worry about my habitat being held hostage in the latter scenario. Has anyone worked out the numbers for the former scenario?

  • GaryChurch March 31, 2013, 13:41

    “This far out, fusion is the only game in town.”

    There is no fusion power yet- and may never be (I am not of the opinion fusion reactors are inevitable.)

    If you are going to send people out there than sending a couple hundred pounds of plutonium to go along with them will power a city in space for several years. A couple tons will last them decades. So I do not follow your reasoning Abelard.

  • GaryChurch March 31, 2013, 14:13

    “I wonder if there are already 1 or many AIs now ‘alive’ and playing dumb in cyberspace.”

    There are some real breakthroughs just around the corner; figuring out how consciousness works is one question that will probably be answered soon. That will be one of those great moments in history I imagine. Artificially creating consciousness may be more difficult.

    I believe that for some reason most people cannot understand what being able to build an intelligence “more than human” means. If we can make it smarter than us it can make itself smarter than we can comprehend. Extremely difficult to wrap our heads around but a few people, like Hugo DeGaris, do understand.

  • ljk April 1, 2013, 9:59

    GaryChurch said on March 29, 2013 at 11:20:

    [LJK] “Using starships as a lifeboat is not our best foot forward on this matter.”

    “Disagree- they are the only foot we have. As Rob Henry commented:

    “Under such circumstances, you can only stay alive, if you forgo the default human belief of a beneficent Mother Nature, and place your faith to science. You can only expect your children to survive if you plan everything with the future in mind.”

    “I would add that mother nature does not care if we thrive or go extinct- that is up to us and since we have this primitive optimism bias keeping us distracted from the inevitable extinction event we are IMO and endangered species.”

    Allow me to clarify: I strongly believe that human expansion into space is what will save our species from degeneration and worse. That being said, I do not think it should be posed to the general public as the main reason for going to the stars in terms of a rescue effort.

    People may appreciate having a lifeboat handy, but they do not consider it a means of main transportation and certainly not something to live in for long periods of time. Plus the negative connotations of some disaster befalling us is never helpful, and quite frankly I had enough of that last year with the whole Maya “prophecy” nonsense.

    On a technical note: Unless we had plenty of warning, trying to build a Worldship to get a few thousand people out of the Sol system (and go where exactly?) would probably not only work but create even more panic and bloodshed as everyone tried to jump in the celestial lifeboat. Much better to have a group of enthusiastic volunteers on a bold venture to the stars.

  • GaryChurch April 1, 2013, 16:06

    “-the negative connotations of some disaster befalling us is never helpful, and quite frankly I had enough of that last year with the whole Maya “prophecy” nonsense.”

    I do not know anything about the Maya prophecy; I did not waste any time on it. Negative connatations are about the ONLY thing that are helpful. An old aviation adage is that improvements require people dying. Sputnik was the negative that produced human beings bunny hopping on the lunar surface.

    In fact, corporations are happy to sit back and make profits on what they are manufacturing but the competition (a negative) constantly reminds executives they are only as good as their last quarter profit margin. This scares them enough to risk investing in new products.

    We need to be scared and not befuddled by Polyanna’s saying everything will be alright.

  • jkittle April 4, 2013, 23:28

    hey everyone forgets that there is lithium present in these comets too, and maybe practical to harvest. it is a WAY better fusion fuel than Deuterium alone.

  • ljk April 5, 2013, 13:39

    Please elaborate on lithium for fusion propulsion, jkittle, thank you.

    My God, was Star Trek not that far off? In at least one early episode, the Starship Enterprise used lithium fuel for its warp drive. They later changed it to dilithium to sound more exotic.

  • ljk April 5, 2013, 13:46

    GaryChurch April 1, 2013 at 16:06:

    [LJK] “-the negative connotations of some disaster befalling us is never helpful, and quite frankly I had enough of that last year with the whole Maya “prophecy” nonsense.”

    “I do not know anything about the Maya prophecy; I did not waste any time on it. Negative connatations are about the ONLY thing that are helpful. An old aviation adage is that improvements require people dying. Sputnik was the negative that produced human beings bunny hopping on the lunar surface.”

    You are mistaking negative with disaster. A negative experience one can learn and recover from to become better is one thing. A disaster which threatens death and extinction is another matter. If you think the need to build a Worldship in a few generations or less would have more benefits than deadly minuses, then be my guest to study how real humans might really react to such a situation.

    A few possible reactions: Mass panic, mass suicides for those unable to escape Earth, and cults declaring that it is God’s Will that no one is suppose to survive His Just Punishment and thus threatening any crew members and those who might build a Worldship.

    THIS is why I am saying we should support the more positive aspects of interstellar exploration and migration.

  • Eniac April 5, 2013, 21:53

    Please elaborate on lithium for fusion propulsion, jkittle, thank you.

    Lithium is a fine fusion fuel, because it fissions easily into tritium and helium under fusion conditions. Most so called “hydrogen bombs” are actually made of lithium deuteride, with the lithium contributing most of the fuel.

    Even the tokamak fusion reactors we are striving to build would run on lithium. The tritium to being burned in them is to be bred on site by fissioning lithium with the help of the neutrons from the fusion reaction itself.

  • GaryChurch April 10, 2013, 1:12

    “-the tokamak fusion reactors we are striving to build would run on lithium-”

    We seem to have been striving for a very long time. I am fascinated by the seeming “inevitability” of fusion reactors when they are discussed. It may be that they will never work. I do not see how we can recreate the conditions in a star without quadrillions of tons of gas creating the gravity to push it together enough to light off. We can obviously do it with explosives to light off a fission bomb to light off an H-bomb, but a continuous reaction?
    I am one of those people that say fusion reactors are NOT inevitable.

  • ljk May 29, 2013, 9:17

    Mysterious and Well-Preserved Oort Cloud Object Heading Into Our Solar System

    by Shannon Hall on May 28, 2013

    What if we could journey to the outer edge of the Solar System – beyond the familiar rocky planets and the gas giants, past the orbits of asteroids and comets – one thousand times further still – to the spherical shell of icy particles that enshrouds the Solar System. This shell, more commonly known as the Oort cloud, is believed to be a remnant of the early Solar System.

    Imagine what astronomers could learn about the early Solar System by sending a probe to the Oort cloud! Unfortunately 1-2 light years is more than a little beyond our reach. But we’re not entirely out of luck. 2010 WG9 – a trans-Neptunian object — is actually an Oort Cloud object in disguise. It has been kicked out of its orbit, and is heading closer towards us so we can get an unprecedented look.

    But it gets even better! 2010 WG9 won’t get close to the Sun, meaning that its icy surface will remain well-preserved. Dr. David Rabinowitz, lead author of a paper about the ongoing observations of this object told Universe Today, “This is one of the Holy Grails of Planetary Science – to observe an unaltered planetesimal left over from the time of Solar System formation.”

    Full article here:

    http://www.universetoday.com/102406/mysterious-and-well-preserved-oort-cloud-object-heading-into-our-solar-system/