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Thread: Callisto colonization -- some crazy ideas

  1. #121
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    Just a note, as sodium chloride might be found on Callisto as well and in its seas:

    https://phys.org/news/2019-06-table-...nd-europa.html

    Table salt compound spotted on Europa
    by Robert Perkins, California Institute of Technology

    A familiar ingredient has been hiding in plain sight on the surface of Jupiter's moon Europa. Using a visible light spectral analysis, planetary scientists at Caltech and the Jet Propulsion Laboratory, which Caltech manages for NASA, have discovered that the yellow color visible on portions of the surface of Europa is actually sodium chloride, a compound known on Earth as table salt, which is also the principal component of sea salt.

  2. #122
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    Quote Originally Posted by Roger E. Moore View Post
    What I am slowly coming to think is that space will be settled by outcasts and dissidents who no longer wish to live on Earth, or, once in space, are unable or unwilling to return. It will not be the thrill of exploration that sends them out. It will be violence and repression, civil war and rebellion, accidents and errors, people of the religious and political margins whose roots may already have been set down.
    My current thinking is that it will primarily come down to technological development. Small scale manufacturing is improving. When you can take a relatively small mass machine somewhere, feed it material onsite and use it to make the (fairly advanced) hardware you need, including more manufacturing equipment, then you have passed one of the big hurdles to expanding (reasonably economically) into the solar system.

    The other key issue is that we will need to be able to make small (fairly) closed ecosystems that can produce a reasonable variety of food (enough to keep people alive and with at least some variation to avoid monotony) and also to be able to maintain breathing air and water for habitats long term. There's been relatively little work done on this so far, it simply isn't a priority yet.

    Once the technology is available, I think there will be people who want to use it. Some may be outcasts, some might simply be people who have always wanted to live somewhere else beyond the Earth.

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  3. #123
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    Quote Originally Posted by Van Rijn View Post
    My current thinking is that it will primarily come down to technological development. Small scale manufacturing is improving. When you can take a relatively small mass machine somewhere, feed it material onsite and use it to make the (fairly advanced) hardware you need, including more manufacturing equipment, then you have passed one of the big hurdles to expanding (reasonably economically) into the solar system.

    The other key issue is that we will need to be able to make small (fairly) closed ecosystems that can produce a reasonable variety of food (enough to keep people alive and with at least some variation to avoid monotony) and also to be able to maintain breathing air and water for habitats long term. There's been relatively little work done on this so far, it simply isn't a priority yet.

    Once the technology is available, I think there will be people who want to use it. Some may be outcasts, some might simply be people who have always wanted to live somewhere else beyond the Earth.
    Yes. Something has to happen to make it all easier.

  4. #124
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    Quote Originally Posted by Roger E. Moore View Post
    Yes. Something has to happen to make it all easier.
    I'm hoping it'll be cheap launches, once the reusable stages get good enough. Then we can loft people, too. And Van Rijn's compact seed-tech (and actual seeds of course) would also help.

    I used to have faith in SSTO carrying payloads up, once upon a time. But like a fairy tale, that was too good to be true.
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  5. #125
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    Quote Originally Posted by Van Rijn View Post
    My current thinking is that it will primarily come down to technological development. Small scale manufacturing is improving. When you can take a relatively small mass machine somewhere, feed it material onsite and use it to make the (fairly advanced) hardware you need, including more manufacturing equipment, then you have passed one of the big hurdles to expanding (reasonably economically) into the solar system.

    The other key issue is that we will need to be able to make small (fairly) closed ecosystems that can produce a reasonable variety of food (enough to keep people alive and with at least some variation to avoid monotony) and also to be able to maintain breathing air and water for habitats long term. There's been relatively little work done on this so far, it simply isn't a priority yet.

    Once the technology is available, I think there will be people who want to use it. Some may be outcasts, some might simply be people who have always wanted to live somewhere else beyond the Earth.
    I agree with that. That is why, I like China's approach. Start with LEO with, not only people(like ISS) but also be almost self sufficient for other needs - grow your own plants for food and oxygen. Have 3D printing for the small repairs etc. Expend this than to the moon base. China is already experimenting with plants that will survive the radiation the moon experiences.
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  6. #126
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    Quote Originally Posted by Roger E. Moore View Post
    The gravity well that O'Neill's followers cursed, even if a fraction of Earth's, might provide more health benefits for colonists than weightlessness. The presence of a thick atmosphere to shield against radiation and meteors is surely beneficial. Digging tunnels and large chambers for underground living is safer and provides more shielding from hazards than living on a space station susceptible to the dangers of spacecraft collision, meteor puncture, systems failures, fires, air loss, and so on.
    As far as weightlessness goes, O'Neill had a solution to that, spin. Fractional gravity may prove more hazardous to human health than the 1G centrifugal force of an orbital habitat. Indeed, it's my number one objection to settling surfaces; nothing in the Solar System has Earthlike gravity except Venus, which comes with its own set of problems.

    As far as fires, look at any Navy vessel and the firefighting gear and drills they run. Fire is always a danger in any kind of vessel, even underground ones. And tunnels have limited escape routes. Air loss: without terraforming Callisto is still largely toxic volatiles. So, still a reason to fear leaks.

    Callisto is still many times better for colonizing than Titan though!
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  7. #127
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    Quote Originally Posted by selvaarchi View Post
    I agree with that. That is why, I like China's approach. Start with LEO with, not only people(like ISS) but also be almost self sufficient for other needs - grow your own plants for food and oxygen. Have 3D printing for the small repairs etc. Expend this than to the moon base. China is already experimenting with plants that will survive the radiation the moon experiences.
    Which nations and groups will eventually colonize the worlds of the solar system? It does make you wonder. I'm just happy that anyone's thinking of it.

  8. #128
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    Hey, found a little bit of Robert Zubrin goodness, and a crazy plan to talk about.

    http://citeseerx.ist.psu.edu/viewdoc...=rep1&type=pdf
    https://web.archive.org/web/20190608...=rep1&type=pdf

    Technological Requirements for Terraforming Mars
    Robert M. Zubrin and Christopher P. McKay
    AIAA-93-2005

    You will be spared the details, except for this: Use space mirrors to evaporate the frozen CO2 at the Martian South Pole to boost the atmosphere. It's a familiar idea. Something like this has been suggested for other worlds as well.

    Except that you have to build enormous mirrors at Jupiter's distance, and stupendous mirrors at Triton's distance.

    If an atmosphere is desired for a giant outer moon--say, Callisto--why not send two giant nuclear-powered heat-producing machines to touch down on the world, one at the north pole and one at the south pole. Callisto is oriented fairly close to Jupiter's orbital plane around the Sun, meaning the poles are the coldest parts of the world (per some of the papers cited in this thread).

    As the giant nuclear heaters warm up the polar regions, hot gases will rise and migrate down toward the equator, where they will sink to the surface (having gotten cooler). The gases will then migrate northward and southward to the poles again, creating air current systems not unlike that which Earth has. The increasing amount of warm gas from the poles, some of which will be greenhouse gas, will raise temperatures across the world, releasing more gas from the soil.

    As before, this is a possible tactic only if producing an atmosphere looks like a good option. It eliminates the need for overlarge solar mirrors, but true, nuclear fuel is very heavy. The heaters would have to be extremely efficient, and the radiator units will get quite hot relative to the local environment. The units should be set on solid rock outcrops so they will not sink into the ice and get broken.

  9. #129
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    Interesting historical note: in 1997, the Artemis Project, devoted to establishing a lunar colony, came up with a detailed plan to colonize Europa because of the subsurface ocean. At the end of the plan, which included building ice "igloos" to stop the fantastic amounts of radiation showering Europa's surface, the workshop participants pointed out in a roundabout way that colonizing Europa was better than colonizing "boring Callisto," which was outside the lethal radiation zone.

    Color me miffed.

    http://asi.org/adb/06/09/03/02/110/europa2-wkshp.html

  10. #130
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    Past "Universe Today" article on colonizing all of Jupiter's moons. Still see Callisto as the main prospect, though it would be nice to get Ganymede in there somehow. Sigh.

    The issue of mining Galilean moons for the nuclear fuel Helium-3 is worth addressing at a later time. It's been cited as a reason for mining the Moon.

    ===

    https://www.universetoday.com/130637...upiters-moons/
    Universe Today: How Do We Colonize Jupiter’s Moons?

    Potential Benefits:
    Establishing colonies on the Galilean moons has many potential benefits for humanity. For one, the Jovian system is incredibly rich in terms of volatiles – which include water, carbon dioxide, and ammonia ices – as well as organic molecules. In addition, it is believed that Jupiter’s moons also contain massive amounts of liquid water.

    For example, volume estimates placed on Europa’s interior ocean suggest that it may contain as much as 3 ◊ 10^18 m^3 – three quadrillion cubic kilometers, or 719.7 trillion cubic miles – of water. This is slightly more than twice the combined volume of all of Earth’s oceans. In addition, colonies on the moons of Jupiter could enable missions to Jupiter itself, where hydrogen and helium-3 could be harvested as nuclear fuel.
    Colonies established on Europa and Ganymede would also allow for multiple exploration missions to be mounted to the interior oceans that these moons are believed to have. Given that these oceans are also thought to be some of the most likely locations for extra-terrestrial life in our Solar System, the ability to examine them up close would be a boon for scientific research.

    Colonies on the moons of Io, Europa, Ganymede and Callisto would also facilitate missions farther out into the Solar System. These colonies could serve as stopover points and resupply bases for missions heading to and from the Cronian system (Saturn’s system of moons) where additional resources could be harvested.

    In short, colonies in the Jovian system would provide humanity with access to abundant resources and immense research opportunities. The chance to grow as a species, and become a post-scarcity one at that, are there; assuming that all the challenges can be overcome.

    CAVEAT:
    The link to the NASA slideshow/article on mining gas giants for Helium-3 does not work. Use this one:

    https://web.archive.org/web/20161222....6_Reinert.pdf
    Van Cleve et. al. “Helium-3 Mining Aerostats in the Atmospheres of the Outer Planets”, 2002

  11. #131
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    Quote Originally Posted by Roger E. Moore View Post
    At the end of the plan, which included building ice "igloos" to stop the fantastic amounts of radiation showering Europa's surface, the workshop participants pointed out in a roundabout way that colonizing Europa was better than colonizing "boring Callisto," which was outside the lethal radiation zone.


    Color me miffed.

    http://asi.org/adb/06/09/03/02/110/europa2-wkshp.html
    Yeah, radiation exposure is so exciting.
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  12. #132
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    Going back to https://forum.cosmoquest.org/showthr...26#post2487126

    Here is a (crude) illustration of how the atmospheric circulation would work on Callisto with nuclear surface heaters at the poles. Radiating surfaces would be extensive and cover a large area of the poles.

    Callisto is small enough that a single rolling cell would likely exist in the northern hemisphere and in the southern. As the heating cycle gets going, more gas will come out of the warming ground the world over.

    NOTE: Ignore the illustration title, I had to modify a Venus atmosphere circulation pattern to make this.

  13. #133
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    Quote Originally Posted by Roger E. Moore View Post
    The issue of mining Galilean moons for the nuclear fuel Helium-3 is worth addressing at a later time. It's been cited as a reason for mining the Moon.
    A later time for Helium-3. (thread)
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  14. #134
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    Quote Originally Posted by Roger E. Moore View Post
    The issue of mining Galilean moons for the nuclear fuel Helium-3 is worth addressing at a later time. It's been cited as a reason for mining the Moon.
    Appears I misread some of the earlier articles, got the mistaken impression that Helium-3 had been found on Jovian moons. It has not. It's in abundance in Jupiter, though, and some have tinkered with plans to mine He-3 from the Jovian atmosphere.

    Setting the record straight.

  15. #135
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    Have a number of things to post about, but need to do the math first.

    Will mention a very interesting article by Jerry Pournelle in his science anthology, A Step Farther Out (1980, paperback, p.203-217). In "Those Pesky Belters and Their Torchships," he discusses the reasons why, because of energy usage, a "Belter civilization" will likely not appear in the asteroid belt. It costs too much in delta-vee, the total change in velocity a spacecraft must make on a journey, to regularly go from one asteroid to another. This is true despite the near-complete lack of deep gravity wells, and the assumption that all missions from one world to another, whether Earth or an asteroid, begin and end in orbit. The very lack of a gravity well makes asteroids harder to reach, even if you take off from one. Pournelle discusses Hohmann transfer orbits, the minimum-energy elliptical orbits, but those turn out to have rendezvous launches that are years apart for asteroids.

    The conclusion was that the energy requirements for asteroid-to-asteroid travel are simply too high. (This would change of course if a cheap, high-energy rocket engine was developed that was easy and cheap to refuel.)

    This problem disappears for the Jovian moon system, however. Pournelle wrote this article in the Olden Days when Jupiter had only XII moons. The good news is that it takes less delta-vee to get to Jupiter than to Ceres, as Jupiter will literally drag you in with its gravity well. If you then flit from moon to moon, you will find it very difficult to get anywhere cheaply from Io inward... BUT getting from Callisto to any other Jovian satellite (except the retrograde ones, which are hard to catch) becomes ridiculously easy. Using NERVA-type engines, a spacecraft could pop around from Europa outward with ease, perhaps even refueling for hydrogen at various moons.

    Dr. Pournelle was highly optimistic about the possibilities of a Jovian moon civilization, but this was before the deadliness of Jupiter's radiation belts was fully known. Yet, from Callisto outward, things look darn good in terms of energy costs and travel times. Delta-vee for trips from Callisto to Hestia, Hera, and Demeter are in the 3.3-3.4 km/sec orbit-to-orbit. He does not give a table of figures, but Pournelle stated that favorable Hohmann orbits appeared every few Earth months, not in terms of Earth years.

    The article's math would have be reworked based on today's knowledge of the moons, but this sounds promising for a Callisto colony's ability to mine some of the outer moons. Because of the difficulty in getting out of Jupiter's gravity well, the Callisto colony would by default need to be self-sufficient and not dependent on shipments of food, etc., from anywhere else.

    This puts a different spin on things in the longer run. A large-population colony on Callisto, with access to spacecraft, robots, and so on, could in practice claim the resources of the entire Jovian system. Certainly outside colonies could move into the system, but cooperation and alliance would work well because of the obvious dangers of the system.

    In short, colonizing some of the larger moons of Jupiter, Callisto in particular, would be similar to colonizing the closely-packed worlds of some M-dwarf stars currently studied, like TRAPPIST-1. Once you get into the gravity well of a red dwarf (or Jovian-type planet), it's going to be very hard to get out. Colonists who go there are there to stay.
    Last edited by Roger E. Moore; 2019-Jun-23 at 06:55 PM.

  16. #136
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    Agree about there not being a unified Belter society. However...

    Everything you said about Callisto would also be true of a station in Callisto orbit. Where's the advantage in a surface settlement? (Don't say gravity. Spin can more than make up for it.)
    Last edited by Noclevername; 2019-Jun-23 at 07:34 PM.
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    Interesting thought, maybe I was too harsh about colonists going to Callisto not being able to leave Jupiter easily and go somewhere else.

    See the link to Wikipedia, which displays a gravity well image from the popular nerd comic site XKCD. Look at the positions of Ganymede at the top of Jupiter's gravity well (next moon inward from Callisto, which is not shown), Titan at the top of Saturn's gravity well, and Neptune (Triton not shown).

    Basically it appears if you live on Callisto, you can cheaply travel (low fuel expenditure) to Titan or Triton, which have also been cited as possibly colonizable with an effort. It might take a while, though you can use Jupiter as a gravity sling which might help. Bigger engines would cut the travel time, but it's not going to be easy in any event.

    Callisto could be the literal gateway to the outer solar system, the St. Louis of space! (Sorry.) Think about it, though. Looking good!

    https://www.explainxkcd.com/wiki/ind...vity_wells.png

  18. #138
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    Quote Originally Posted by Noclevername View Post
    However...

    Everything you said about Callisto would also be true of a station in Callisto orbit. Where's the advantage in a surface settlement? (Don't say gravity. Spin can more than make up for it.)
    I think that in the thread on Titan, Swift warned us not to get into this discussion, but I could be wrong. Just in case, it might be better to take that discussion to a more general thread?



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  19. #139
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    Ha! Was poking around on Amazon-dot-com, looked at Robert Zubrin's Entering Space. If you "Look Inside!" and search for Callisto, he gives an amusing and enlightening story about how Callisto's future colonists could use the gravity well of Jupiter to slingshot their produce to other worlds in the Solar System (here, Titan).

    Use the link to visit the book, and look up the Callisto story. It's great.

    https://www.amazon.com/gp/product/15...t_bibl_vppi_i5

  20. #140
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    Quote Originally Posted by Noclevername View Post
    Agree about there not being a unified Belter society. However...

    Everything you said about Callisto would also be true of a station in Callisto orbit. Where's the advantage in a surface settlement? (Don't say gravity. Spin can more than make up for it.)
    You were warned to stay on-topic in the Titan thread. That applies to that thread, this thread and any other thread. Stay on-topic. If you wish to discuss orbital/space colonies, start another thread.
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  21. #141
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    Callisto is one of the few giant satellites in the Solar System to be able to have a satellite in orbit around it.

    The math suggests that the Hill sphere for Callisto is about 50,000 km from the world's center. Attached is a table of the Roche limits for Callisto, depending on the density of the satellite. Hope I got that worked out right.

    The point? People have talked about moving asteroids into close orbit around the Earth to mine them. Maybe we could move some of Jupiter's tiniest moonlets (< 1 km diam) into orbit around Callisto, if Callisto is missing materials the moonlets are not.
    Attached Images Attached Images
    Last edited by Roger E. Moore; 2019-Jun-25 at 12:15 AM.

  22. #142
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    Quote Originally Posted by Roger E. Moore View Post
    Dr. Pournelle was highly optimistic about the possibilities of a Jovian moon civilization, but this was before the deadliness of Jupiter's radiation belts was fully known. Yet, from Callisto outward, things look darn good in terms of energy costs and travel times. Delta-vee for trips from Callisto to Hestia, Hera, and Demeter are in the 3.3-3.4 km/sec orbit-to-orbit.
    Was not aware Pournelle was using outmoded names for some of the prograde Jovian moons. I grew up using the same names. Oh, well. Below is a table from Wikipedia, somewhat modified, with the moons' real names and basic information on currently known outer prograde satellites, which are easier to reach from Callisto as they revolve in the same direction. Miners from Callisto could tear them apart for resources or use them as space bases for whatever needs they have.
    Attached Images Attached Images

  23. #143
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    Just discovered this Wired article on cylindrical robots with lasers, built to drill through the ice on moons like Callisto. Great illo.

    https://www.wired.com/2012/04/bill-s...-europa-rover/
    Attached Images Attached Images
    Last edited by Roger E. Moore; 2019-Jun-27 at 01:44 AM.

  24. #144
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    Another type of centrifugal gravity generator, this one a flat disk. Could make colonizing any world easier from a health viewpoint.

    https://phys.org/news/2019-07-artifi...e-fiction.html

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    Colonizing Callisto would allow for continuous study of "idyllic" Europa, which still has a significant pull among space scientists. The relative ease with which spacecraft can maneuver between satellites in the Jovian system is a big asset.

    https://www.wired.com/story/forget-t...dyllic-europa/

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