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Thread: Callisto colonization -- some crazy ideas

  1. #61
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    What about noble gases like argon? Curiously, there might not be any noble gases in Callisto's evolving atmosphere, just as there are almost none in Titan's (except for argon). See below.

    https://arxiv.org/abs/1108.4830

    Removal of Titan's Atmospheric Noble Gases by their Sequestration in Surface Clathrates

    Olivier Mousis, Jonathan I. Lunine, Sylvain Picaud, Daniel Cordier, J. Hunter Waite Jr., Kathleen E. Mandt (Submitted on 24 Aug 2011)

    A striking feature of the atmosphere of Titan is that no heavy noble gases other than argon were detected by the Gas Chromatograph Mass Spectrometer (GCMS) aboard the Huygens probe during its descent to Titan's surface in January 2005. Here we provide an explanation of the mysterious absence or rarity of these noble gases in Titan's atmosphere: the thermodynamic conditions prevailing at the surface-atmosphere interface of the satellite allow the formation of multiple guest clathrates that preferentially store some species, including all heavy noble gases, over others. The clean water ice needed for formation of these clathrates could be delivered by successive episodes of cryovolcanic lavas that have been hypothesized to regularly cover the surface of Titan. The formation of clathrates in the porous lavas and their propensity for trapping Ar, Kr and Xe would progressively remove these species from the atmosphere of Titan over its history. In some circumstances, a global clathrate crust with an average thickness not exceeding a few meters could be sufficient on Titan for a complete removal of the heavy noble gases from the atmosphere.

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    The original point of this thread was to post an idea for a way to get essentially infinite subsurface hydroelectric power from Callisto.

    It occurred to me that there might be a way of harnessing some of the energy (if any) that is generated by Callisto's orbit through Jupiter's magnetic field. Other posters can tell me if this is impractical or impossible, but it seemed worthy of mention. Callisto has no magnetic field, but again there's that sloshing subsurface ocean, which does have magnetic effects in Jupiter's aurorae. Who knows.

  3. #63
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    Quote Originally Posted by Roger E. Moore View Post
    One particular advantage of terraforming Callisto is that the process could be completely performed by robots, which eliminates the need to send humans to the world, putting them at risk of death from radiation, etc.
    Then who are you terraforming it for?
    "I'm planning to live forever. So far, that's working perfectly." Steven Wright

  4. #64
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    Quote Originally Posted by Noclevername View Post
    Then who are you terraforming it for?
    Humans, once we figure out how to get them there. They do not need to die during the making of the world, however.

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    Quote Originally Posted by Roger E. Moore View Post
    Humans, once we figure out how to get them there. They do not need to die during the making of the world, however.
    It's actually safer and more convenient for colonizing to leave it as is. Terraform it, and the surface gets harder to build on, and more chaotic and dangerous. And colder, atmosphere would carry away heat.
    "I'm planning to live forever. So far, that's working perfectly." Steven Wright

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    Quote Originally Posted by Noclevername View Post
    It's actually safer and more convenient for colonizing to leave it as is. Terraform it, and the surface gets harder to build on, and more chaotic and dangerous. And colder, atmosphere would carry away heat.
    Could be. Just playing with ideas, trying to see if something catches fire.

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    Quote Originally Posted by Noclevername View Post
    It's actually safer and more convenient for colonizing to leave it as is. Terraform it, and the surface gets harder to build on, and more chaotic and dangerous. And colder, atmosphere would carry away heat.
    The surface is about as beaten up as it can get. It should bulldoze without a lot of trouble, except for the extreme cold. Photos of the surface show a lot of eroded crater rims and peaks, about as rough a terrain as one could imagine. Maybe sending very large bulldozers or earth-movers would work, again just with robots.

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    Quote Originally Posted by Roger E. Moore View Post
    The surface is about as beaten up as it can get. It should bulldoze without a lot of trouble, except for the extreme cold. Photos of the surface show a lot of eroded crater rims and peaks, about as rough a terrain as one could imagine. Maybe sending very large bulldozers or earth-movers would work, again just with robots.

    But you can always melt/refreeze it into whatever shapes needed. Hover a sufficiently large rocket over a crater and boom, parking lot.
    "I'm planning to live forever. So far, that's working perfectly." Steven Wright

  9. #69
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    Quote Originally Posted by Noclevername View Post
    But you can always melt/refreeze it into whatever shapes needed. Hover a sufficiently large rocket over a crater and boom, parking lot.
    Yes, but part of the surface is just rock, part is dust, part is frozen ices of a half-dozen kinds, it's just a frozen Rocky Road planet.

  10. #70
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    Quote Originally Posted by Noclevername View Post
    But you can always melt/refreeze it into whatever shapes needed. Hover a sufficiently large rocket over a crater and boom, parking lot.
    Let's go with the leave-Callisto-frozen idea.

    I looked up this possibility. One of the difficulties is that once the volatile substances are evaporated (if landers have fiery exhausts), an enormous amount of chaotic rock and dust is left, much of it in the form of very loose regolith with steep rocky hills (like knobs) poking out everywhere. On the good side, you certainly can bulldoze it, but you must also pack it down hard. The parking lot idea is dead on, you are totally right, you need to build a landing field for spacecraft coming in. That would have to be the first mission of a permanent colony crew, picking out a near-equatorial site (to get the most heat in daytime) and then creating a safe place for everything coming in afterward to land and offload. The landing spot would need to be solid enough to support spacecraft many tons in weight.

    Tunneling is necessary, and it might work to tunnel straight into the side of one of those rocky knobs. So you want a generally flat spot next to a good-sized hill near the equator.

    LATE ADD: Occurs to me that drilling will be difficult, as melted ices will refreeze almost instantly. The drill itself will have to be hot to keep from being locked in place by ice.

    .
    Last edited by Roger E. Moore; 2019-Jun-06 at 02:28 PM.

  11. #71
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    So, where to set up a base? Depends on whether you are looking for long-term survivability, exploration of giant craters, or making observations of Jupiter and the other inner moons.

    Go to the Astronomy thread on Callisto's cartographic system: https://forum.cosmoquest.org/showthr...70#post2482170 . Diagrams from this site are needed.

    Now look at the attached image from that textbook article, Chapter 17, on Callisto: http://lasp.colorado.edu/~espoclass/...ework/Ch17.pdf

    Okay, now the point on the map at 0° longitude and 0° latitude is the Sub-Jovian Point, the place at which Jupiter is exactly overhead (at zenith). Go to the left, to the 90° longitude 0° latitude point. That is the Orbital Apex, the exact "leading edge" of Callisto in its orbit around Jupiter.

    Notice where all the gigantic craters are, Valhalla and Asgard and so on: right smack on the side facing into its orbit, the leading side. Note that the trailing side of Callisto has few visible giant impacts. You want to put a safe base on or around 270° longitude, 0° latitude, the Orbital Antapex.

    If you wish, you can put your base at the Sub-Jovian Point, but there is a small risk of being hit by an asteroid. (Like what happened at Heimdall.)

    To get the most out of local temperatures, you want to be near the equator, or within 2° of it north or south, to be in range of the Subsolar Point, where the Sun is 90° straight overhead at zenith. The poles are going to be too cold.
    Attached Images Attached Images
    Last edited by Roger E. Moore; 2019-Jun-06 at 02:08 PM.

  12. #72
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    ANOTHER crazy idea for colonization of Callisto: try to give it a magnetosphere. It has an ionosphere but not a magnetosphere.

    This one could be tough. Ganymede has a magnetosphere that comes from a rotating iron core. Callisto apparently does not have a core (see attached NASA art), but it gets a magnetic moment from having a subsurface ocean with ionized particles, making the liquid water electrically conductive. Is it possible to pump locally obtained ionized substances into the underground sea, by way of a VERY deep well, to make the sea even more conductive? Would this lead to Callisto getting a magnetic field? Just a thought. A better ionosphere would also be nice, good for radio.

    ===

    References:

    https://science.sciencemag.org/content/289/5483/1340
    Galileo Magnetometer Measurements: A Stronger Case for a Subsurface Ocean at Europa
    Margaret G. Kivelson, Krishan K. Khurana, Christopher T. Russell, Martin Volwerk, Raymond J. Walker, Christophe Zimmer
    Science, 25 Aug 2000

    http://cdsads.u-strasbg.fr/abs/2000Icar..147..329Z
    http://www.igpp.ucla.edu/people/mkiv...CRUS147329.pdf (full paper)
    Subsurface Oceans on Europa and Callisto: Constraints from Galileo Magnetometer Observations
    Christophe Zimmer, Krishan K. Khurana, Margaret Kivelson
    Icarus, Volume 147, Issue 2, pp. 329-347 (2000).
    Magnetic field perturbations measured during Galileo flybys of Europa and Callisto are consistent with dipole fields induced by the temporal variations of the ambient jovian magnetospheric field. These fields are close to those expected for perfectly conducting moons. We investigate the implications of these observations for the electrical structure of the moon's interiors using a simple shell model. It is found that Europa and Callisto must possess regions where the conductivity exceeds 0.06 and 0.02 S/m at a depth of less than 200 and 300 km below the surface, respectively. This conductivity is unattainable in ice or silicates, unless the ice layer is at least partially molten or very large temperature gradients can be maintained below the ice. An ionosphere or a cloud of pick-up ions are probably also insufficiently conductive. Global Earth-like oceans under the surface of both moons could account for the observations provided they are at least a few kilometers thick.

    Intriguing recent paper:

    https://agupubs.onlinelibrary.wiley....2/2015JA021212
    Callisto plasma interactions: Hybrid modeling including induction by a subsurface ocean
    Jesper Lindkvist, Mats Holmström, Krishan K. Khurana, Shahab Fatemi, Stas Barabash
    First published: 04 June 2015
    Attached Images Attached Images
    Last edited by Roger E. Moore; 2019-Jun-06 at 04:20 PM.

  13. #73
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    Quote Originally Posted by Roger E. Moore View Post
    LATE ADD: Occurs to me that drilling will be difficult, as melted ices will refreeze almost instantly. The drill itself will have to be hot to keep from being locked in place by ice.
    A hollow drill with steam sprayed down the middle? Soften the ice and free the drill at the same time.

    How much will friction heat the drill bit?
    "I'm planning to live forever. So far, that's working perfectly." Steven Wright

  14. #74
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    Quote Originally Posted by Noclevername View Post
    A hollow drill with steam sprayed down the middle? Soften the ice and free the drill at the same time.

    How much will friction heat the drill bit?
    If you have steam being sprayed down the middle, then it will just melt the ice, and let the shaft drop down. Drill only required when it hits solid rock.
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    Quote Originally Posted by selvaarchi View Post
    If you have steam being sprayed down the middle, then it will just melt the ice, and let the shaft drop down. Drill only required when it hits solid rock.
    Want to avoid spraying hot water around, wasting drinking water and having it refreeze instantly, but that would work. Prefer having drill hollow but no hot water getting out, just heating up the bit.

  16. #76
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    If we use tunneling machines, generating heat won't be the problem. They have big engines. Hitting pockets of disruptive volatiles or falling into open spaces might be, though. Maybe we'd have to melt/re-freeze on a large scale to prep the ground for the tunneling machines.
    "I'm planning to live forever. So far, that's working perfectly." Steven Wright

  17. #77
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    Quote Originally Posted by Noclevername View Post
    If we use tunneling machines, generating heat won't be the problem. They have big engines. Hitting pockets of disruptive volatiles or falling into open spaces might be, though. Maybe we'd have to melt/re-freeze on a large scale to prep the ground for the tunneling machines.
    Didn't think about that. Well, the robots knew the job was dangerous when they took it. When they were assigned to it, I mean.

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    For some reason I've had visions of solar panels set up all over the place on Callisto to collect solar energy to power stuff. Then I did some math.

    Solar constant on Earth (measured in 2011 by satellite, here: https://agupubs.onlinelibrary.wiley....9/2010GL045777 ), is 1.3608 kilowatts per square meter. Jupiter is farther out...

    Aphelion 5.4588 AU --> 0.033559 illumination of Earth --> 0.055535 kilowatt hours per square meter, &
    Perihelion 4.9501 AU --> 0.04811 illumination of Earth --> 0.045667 kilowatt hours per square meter. Would that even light a cigarette?

    To get the same solar power as received at Earth, solar arrays on Callisto would have to take up about 18-22 times the area of a similar solar-cell array here.

    Okay, so that's not going to work. Until the robots can dig down to the subterranean sea and set up a power station using that, it's nuclear power, maybe mixed with steam power for some uses.

  19. #79
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    Was thinking about Callisto's motion through the outer magnetosphere of Jupiter, geomagnetic storms, ring current, etc.

    Thought experiment: if you strung a long piece of highly conductive wire out on Callisto's surface--wire that is kilometers long--would Jupiter's magnetic field generate current along it? How about during a solar storm?

    Can't find an answer to this, sort of interesting. On Earth, when a severe geomagnetic storm occurs, long wiring will heat up from current, as will long metal pipes and rails.

    LATE ADD: Does it matter here that Callisto does not rotate on its axis?
    Last edited by Roger E. Moore; 2019-Jun-07 at 03:31 PM.

  20. #80
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    You could always use the other Galilean moons as power stations, and transfer the energy to Callisto. Send magnets.
    "I'm planning to live forever. So far, that's working perfectly." Steven Wright

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    On the warm-up-Callisto plotline, we have an interesting 2006 article from CBS News in which grad student Margarita Marinvoa (now full scientist with a long list of works in the NASA ADS search engine) was interviewed. She had an idea, which was to ship a certain super-greenhouse gas to Mars to warm it up.

    ===

    https://www.cbsnews.com/news/red-planet-turning-green/
    "Red Planet Turning Green?"

    ..."What we propose is to use greenhouse gases – the same ones that are currently on the earth causing climate change," said Margarita Marinova, a graduate student at the California Institute of Technology. That's right. Earthlings are thinking of using the same toxic stuff already blamed for global warming here to put some life back on Mars. Marinova says that the goal is to warm Mars enough so that the planet's south polar cap will evaporate.
    ...As Marinova explains it, the devil's in the details. And the little devil's name is octafluoropropane. "This is our favorite molecule," Marinova said.

    ===

    Would this work on Callisto? Would octafluoropropane heat up Callisto in record time? How would it break down in time?

  22. #82
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    This thread is kind of a stream-of-consciousness brainstorming thing, random thoughts everywhere.

    Discovered this paper, which outlines a terraforming system for Mars similar to what others have considered for Callisto. Adds a good word to the vocabulary, too.

    ===

    http://cdsads.u-strasbg.fr/abs/1992AdSpR..12..133H

    The implantation of life on Mars: Feasibility and motivation
    Haynes, Robert H.; McKay, Christopher P.
    Advances in Space Research, Volume 12, Issue 4, p. 133-140. (1992)

    Environmental conditions on Mars are extremely hostile, and would be destructive to any organisms which might arrive there unprotected to-day. However, it is a biocompatible planet. Its unalterable astrophysical parameters would allow the maintenance of a much thicker, warmer carbon dioxide atmosphere than that which currently exists. Though very cold (averaging about -60°C), highly oxidizing and desiccated, Mars may possess substantial quantities of the materials needed to support life - in particular, water and carbon dioxide. A general scenario for implanting life on Mars would include three main phases: (1) robotic and human exploration to determine whether sufficiently large and accessible volatile inventories are available; (2) planetary engineering designed to warm the planet, release liquid water and produce a thick carbon dioxide atmosphere; and (3) if no indigenous Martian organisms emerge as liquid water becomes available, a program of biological engineering designed to construct and implant pioneering microbial communities able to proliferate in the newly clement, though still anaerobic, Martian environment. The process of establishing an ecosystem, or biosphere, on a lifeless planet is best termed 'ecopoiesis.' This new word, derived from Greek, means `the making of an abode for life.' It is by no means clear whether ecopoiesis on Mars is scientifically possible or technologically achievable. Thus we urge that it be one of the objectives of space research during the next century to assess the feasibility of ecopoiesis on Mars.

    ===

    It strikes me that Callisto has enormous potential in the human exploration and settlement of space, so adding an ecosystem there is worth studying.

  23. #83
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    Quote Originally Posted by Roger E. Moore View Post
    Would this work on Callisto? Would octafluoropropane heat up Callisto in record time? How would it break down in time?
    So far I've only found references for how octafluoropropane would act under Earthly sea level conditions; it would be long lasting and stable. It has yet to be determined how it would break down on a Jovian moon, especially if interacting with volatiles released from the ice.
    "I'm planning to live forever. So far, that's working perfectly." Steven Wright

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    Quote Originally Posted by Noclevername View Post
    So far I've only found references for how octafluoropropane would act under Earthly sea level conditions; it would be long lasting and stable. It has yet to be determined how it would break down on a Jovian moon, especially if interacting with volatiles released from the ice.
    That is a pickle. I did find a webpage about Ms. Marinova's project, in a website about terraforming. Totally unexpected.

    https://web.archive.org/web/20190120...marsfront.html

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    Quote Originally Posted by Roger E. Moore View Post
    It strikes me that Callisto has enormous potential in the human exploration and settlement of space, so adding an ecosystem there is worth studying.
    Giving it an atmosphere would make aerobraking easier, at least. And give additional c-ray shielding.

    But an open, uncontained weather-and-ecosystem is by nature chaotic. Storms and stampedes and icequakes, and eventually wind and waves. All the difficulties of settling a water world. Plus the long waiting period until it gets to that point, as opposed to settling on it within a century as-is.
    "I'm planning to live forever. So far, that's working perfectly." Steven Wright

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    Did some math on a Callisto calendar. Its synodic day is 16.753553 Earth days (402.085263 Earth hours), say from one Sun-Callisto-Jupiter alignment to the next. The calendar in any form would include solar eclipses (when Jupiter covers the Sun), "lunar" eclipses (when Callisto's shadow falls on Jupiter), and aphelion (coldest time of year) and perihelion ("warmest" time of year).

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    Quote Originally Posted by Noclevername View Post
    Giving it an atmosphere would make aerobraking easier, at least. And give additional c-ray shielding.
    Having an atmosphere to cut down on cosmic radiation strikes me as a superb thing, though the cosmic rays will produce damaging muons, as they do on Earth.

    The good news is that a substantial & dense atmosphere, as mentioned earlier, would extend way above the ground, many times higher than Earth's atmosphere, giving more shielding from radiation of all kinds. Jupiter's magnetosphere would be a huge help here was well, blocking solar storm radiation.

    Found another diagram of Titan's atmosphere from Wikipedia. The article is worth reading for implications for Callisto's atmosphere, if one is created.

    https://en.wikipedia.org/wiki/Climate_of_Titan
    Attached Images Attached Images

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    I can see a Callisto with an atmosphere but arctic-like surface conditions. Mobile habs rest on the icecap, with ice domes to add shielding and regulate temperatures. Heat and power by "outbuilding" reactors (preferably fusion, if we have that by then). A town rolling on bearings, surrounded by several power plants.
    "I'm planning to live forever. So far, that's working perfectly." Steven Wright

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    Quote Originally Posted by Noclevername View Post
    But an open, uncontained weather-and-ecosystem is by nature chaotic. Storms and stampedes and icequakes, and eventually wind and waves. All the difficulties of settling a water world. Plus the long waiting period until it gets to that point, as opposed to settling on it within a century as-is.
    The more I get into thinking of Callisto as a place of human settlement, in whatever form, the less concerned I get about the timetable. Time would affect funding, of course, can't forget that. But I keep thinking of robots doing the hard work, not humans, building a place to which humans can migrate when the travel problems have been resolved. The Moon and Mars are more like immediate concerns, opposed to Callisto which is a long-term thing.

    Not sure how chaotic it would be to have a small world with an atmosphere. It would always be cold there, no matter what we did (even with greenhouse gases), and the air is likely to stay unbreathable because of gases sublimating from the soil. But you could see clearly in daytime (big atmosphere scattering weak sunlight), possibly wear a comfortable enclosed warm body suit, do some lichen gardening and grow food, maybe even develop an Earth-derived native ecology that would be unique to the universe.

    AND live in underground chambers where it was safer. I don't think now it would warm up enough to melt very much, not sure. Maybe we could get the best of both worlds.

    Mars would be safer to terraform in the long run, but even then it would have a lot of carbon dioxide in the air for many years. You could walk around in warm clothing with an air mask on. Incoming radiation would be a problem.

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    Quote Originally Posted by Noclevername View Post
    I can see a Callisto with an atmosphere but arctic-like surface conditions. Mobile habs rest on the icecap, with ice domes to add shielding and regulate temperatures. Heat and power by "outbuilding" reactors (preferably fusion, if we have that by then). A town rolling on bearings, surrounded by several power plants.
    Very likely, yes.

    Wait, rolling on bearings?

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