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Ride a Comet

  1. Jul 25, 2007 #1
    This might be a good idea for a thesis.

    Could we alter a comet's course and make it break free of orbit and head towards another sun and populate other planets?

    Some of them are made up of life sustaining elements right?

    Could we use nuclear power to melt it to create a biosphere?
     
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  3. Jul 25, 2007 #2

    mgb_phys

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    Just provide enough delta V and you can put it anywhere you like.
    Tricky bit of targeting but in theory yes.

    Probably not. Fred Hoyle aside there is no evidence of life on comets. Organic molecules have been found on comets but they are also found in gas clouds in space. If you put enough carbon/hydrogen/oxygen together for long enough you are pretty much bound to form at least sugars and simple amino acids. This doesn't mean that those same molecules had to have come from comets or couldn't have formed on earth.

    You can melt it but; a, there isn't necessarily a surface on a comet it's more like a bunch of rocks stuck together with ice/snow and b, if you melt it there isn't enough gravity in a comet to stop it immediately evaporating into space.
     
  4. Jul 25, 2007 #3
    Cool that it's possible to get the comet there. Let me clarify on the rest.

    I meant we'd populate other planets by traveling to the comets, drilling into them and creating a place to live underground.

    I was thinking that some comets are made of ice and other organic compounds so maybe we could melt and use them to sustain a biosphere we built there.

    Looking forward to more of your thoughts. I don't know the theory or math, just an out of the box thinker looking for answers to the crazy questions that pop into my head.
     
    Last edited: Jul 25, 2007
  5. Jul 25, 2007 #4

    mgb_phys

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    If you had enough rocket power to push the comet out of orbit you would probably be better off using that same amount of power to just send a ship.
    You could pick up some water from a comet on the way to save lifting it out of earth orbit but recycling systems are pretty good so you don't really need much water/organic chemicals.
    Comets don't make a very stable/habitable place to live - although a long distance from the sun they wouldn't be so active.

    The organics bit is a common crank/alternative heory that since we find organic molecules in comets and comets land on Earth then life must have come from comets.
     
  6. Jul 25, 2007 #5
    Wouldn't it be better to use a comet since it will stabalize when it gets away from the sun and since it would be bigger than anything we could build it might protect us from space debris.

    I'm not claiming that comets brought life to earth, im theorizing that we could use comets to take us to other planets.
     
  7. Jul 25, 2007 #6

    DaveC426913

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    1] Well, if you bring anything that produces heat, it seems to me you could turn the comet into its own propulsion couldn't you? You''d just park your heater on the comet's surface opposite to where you want to go and turn it on.
    2] How did we get to talking about life on comets or coming from comets? Seems to me the OP's simply saying it contains the raw materials (C,O,H) for us to mine.
     
  8. Jul 26, 2007 #7

    mgb_phys

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    Yes - I misunderstood the OP to be saying we could seed life on other planets by firing comets at them.
     
  9. Aug 19, 2007 #8
    I suppose if you were lucky enough to find a comet that is already going to be ejected from the Solar System (i.e. - due to a close encounter with Jupiter), then you wouldn't have to worry about pushing the cometary mass. You could just power a smaller-mass ship to match velocities and land on it.

    Of course, you'd have no control over where you are going, and you wouldn't get there very fast (maybe a few km/s above Solar escape velocity).
     
  10. Aug 20, 2007 #9

    tony873004

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    Which means it would take you 100s of thousands of years to get to Alpha Centauri, if you happened to be aimed that way.
     
  11. Oct 1, 2007 #10
    Thanks for your input everyone. Got more?

    So comets that are already moving out of the solar system are too slow to just hop on board and fly out of the solar system. Are there any comets that are moving signficantly faster? What if we steered one of those? What if we just fired rockets on the side with some phat 1957 fins. Could we drive a comet around the galaxy? the universe?

    Even if it took 100,000's years it would be worth it if our planet was toast for one reason or another and we found another suitable one. Would there be enough "stuff of life" to mine to last long enough to reach other stars on the average comet?
     
  12. Oct 1, 2007 #11

    mgb_phys

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    You could drive a comet around but there is no advantage since it takes energy to push that extra mass. It would be like deciding to cross the atlantic by sending a tug out to find an iceberg and then using the tug to push the iceberg across the ocean - you can do it but there isn't much point.
    If you need the water/chemicals on the comet you are better off just grabbing those onto your ship and not bothering to move the rest of the mass.
     
    Last edited: Oct 1, 2007
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