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Habiting a planet

  1. Aug 30, 2007 #1
    The only way the human race can really have a good chance of surviving in the long run is if we habit other planets then the earth. I figure that some planets may be habitable but without water, heat, and energy, it is a waste of money. Most planets are just not in the right spot to where great temperatures and atmospheres can help us. I have been thinking a lot about the future of power though. Is it possible that if we developed such a great source of power that we could heat a planet from the inside out rather the inside in. For the most part the earth receives energy from the sun and it soaks down, so to say, into the earth and warms it up. I think the daily input of energy is somewhere in the PetaWatt range . Why couldn't we have our own source of heat deep down in a planet to make it habitable. This power source is very much out of our touch for now but would it work is the question?
  2. jcsd
  3. Aug 30, 2007 #2
    Sounds like overkill, to try heating an entire planet from its core, when all that's needed is climate control inside of a few buildings.
  4. Aug 31, 2007 #3


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    Or use that power source to move the planet to the habitable zone.
    - your power source only needs to supply power for a few years rather than for all eternity
    - you don't have to live on a planet whose environment is topsy turvy.
  5. Aug 31, 2007 #4
    I understand that, but is it possible. Would it make the planet habitable like earth if you could supply the correct amount of power?
  6. Aug 31, 2007 #5


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    Well, there's far more to the question than simply energy input. As we all know, the Earth's life-supporting environment is far from "robust," and in some senses balances on the head of a pin.

    - Warren
  7. Aug 31, 2007 #6


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    It is theoretically possible to provide sufficient heat from an internal power source to balance the heat of solar energy influx, yes.
    Definitely a no on that one.

    All terrestrial (land-based) life and much** marine life has - at the foundation of its food chain - solar energy. All plant life on the Earth takes it energy from the sun by way of chlorophyll. All animals, herbivores and predators alike, have plant life as their foundation. No solar energy = no Earth-like life.

    **there are exceptions around geothermal vents in the deep oceans, but that would make for a VERY different planetary biosphere.
    Last edited: Aug 31, 2007
  8. Sep 6, 2007 #7
    We could just use a giant telescope to light the planet up more. There's an idea! :D
  9. Sep 7, 2007 #8
    What choice do we have?

    Hi guys and gals
    I am under the impression that as time passes, we as a species will be forced to make many decisions concerning our continued existance on Terra.
    Our resources here are limited, and we are rapidly growing in numbers. By 2020, there may be 12 billion of us.
    It seems only logical that we will follow our colonization history of the last 1000 years, and get onto other planets.
    Mars and Venus are options, as is Luna, and the Jovian Satellites.
    Mars will be easier than Venus, but in terms of our current knowledge, Venus will not be impossible. A few basic laws of physics will assist us in this process. (ask me!)
    Unless we are prepared to cull large numbers of humans, (try killing 9 000 000 000 humans )we will be forced to colonize Sol's planets and moons. For now. Later, we will do the Jump to other planets, in other Solar Systems.
    None of this, is currently impossible.
    My question is: will the Chineses and Indians beat us to it, while we deliberate funding for the projects...
    What do you all think?
  10. Sep 7, 2007 #9
    Close enough....

    That's quite a good idea... we could use mirrors to focus what light there was, and warm the icy crust...?
  11. Sep 7, 2007 #10
    If light is the substance needed to create and maintain life as we know it, why not just convert all forms of available energy to the "light" we need, and use this to irradiate the area we want to live in. You can grow plants in artificial light...
  12. Sep 7, 2007 #11
    It might be usefel to live on such a planet if you were wanting to use wind or geothermal turbines!
  13. Sep 13, 2007 #12
    Light is required for photosynthesis but it need not be of solar origin; plant factories lit by large sulfur-vapor lightning systems powered by controlled nuclear fusion power plants for example could provide energy flow not involving a natural sun which could still none-the-less sustain life.
  14. Sep 15, 2007 #13
    Mining and manufacturing on the moon:
    http://aerospacescholars.jsc.nasa.gov/HAS/cirr/em/6/6.cfm [Broken]

    we are not faraway from the day before we can inhabit the moon..

    He-3 as a fuel..
    Iron manufacturing units..

    46% oxygen in the crust
    Polar ice..
    Last edited by a moderator: May 3, 2017
  15. Sep 24, 2007 #14
    Maybe heating a planet from the inside isn't so absurd. After all, tidal forces will do it, and to create tides you merely need to add a nearby moon. Given a long view (centuries), a large stock of disposable astronomical bodies of various sizes, and some really clever orbital mechanics...
  16. Sep 24, 2007 #15


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    Thing is, as with all these ideas, you need some vast amount of power to set it up in the first place - why not just use that power source to power your civilization?

    The key, in fact, is to rape the environment :rolleyes: - take advantage of a natural, pre-existing source of potential energy.
  17. Sep 25, 2007 #16


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    for starters, thermodynamics suggests Europa because of the large temperature difference between the deep liquid water phase and the much colder surface

    one could generate power with off-the-shelf technology. using a working fluid that boils at around 270 kelvin.

    one might perhaps use that power to illuminate caves deep in the ice
    and create an earth-like environment in artificially-lit ice-caves.

    Ganymede and Callisto could also have usable temperature gradients, and might for some reason be more easily colonized than Europa. I don't know the details, and mention the latter only because it has long been thought to have liquid water some kilometers down below the ice surface.

    I think the problem, initially at least, is not to *terraform* other bodies, but instead to ADAPT bio-civilization to thrive in other environments----in essence instead of hoping to terraform europa one tries to to "europa-form" terran life.

    e.g. you skate thru ice-tunnels between bubbles, to visit people in a neighboring settlement. an illuminated bubble community could have a lake with fish. maybe some trees, reasonably familiar food, temperature, pressure etc.
    Last edited: Sep 25, 2007
  18. Sep 25, 2007 #17
    This is where the "clever orbital mechanics" comes in. The idea is to have such-and-such asteroid make ever so slight a change of orbit so that it happens to come under the sway of such-and-such planet and undergo a massive change in orbit. It seems like it should be possible to play quite a game of chess with a new planetary system at your disposal and no environmental restrictions.

    Of course, it makes more sense to heat a few buildings if you're putting up a few buildings. But generally if you're going to live on an ice-ball, it won't be long until you want to use it all. There are few reasons to maintain parks of natural terrain - every road, farm, nature preserve etc. all has to be heated and kept in Earthlike conditions. You'd roof the whole planet if you had to roof it. So you might look to heating the whole planet instead.

    It is true that heating the core of a planet is something of a waste except in the most extreme long term, and for many applications atmosphere-down approaches make more sense. A geologically dead planet can be much more convenient. But it doesn't seem so impossible.
  19. Sep 28, 2007 #18
    He3 is not a possible fuel for fusion and is a common misconception, there are many detailed explanations in regard to this and one article in Physics World (this month's I think) encouraging physicists to squash it.

    In regard to Euroaa-forming life. I think this has been discussed somewhat already and actually genetic engineering could be the key. Why not adapt humans to be able to live in more alien environments? They would no longer be suited to life on Earth and wouldn't really be humans anymore but it would be a lot less energy to do this than terraform a whole world.
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