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Any more earths?

  1. Apr 9, 2009 #1
    any more earths???

    like earth, will the other planets makes organic evolution in the near future???
     
  2. jcsd
  3. Apr 9, 2009 #2

    russ_watters

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    Re: any more earths???

    Unlikely. Conditions on the other planets in our solar system are not favorable toward life.
     
  4. Apr 9, 2009 #3

    DaveC426913

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    Re: any more earths???

    Look up the "Goldilocks Zone". It refers to the stellar systemic zone in which planets can harbour water-based life. Earth is the only one in it. Mars is right on the edge.
     
  5. Apr 24, 2009 #4
    Re: any more earths???

    can we create artificial organic evolution in other planets?
     
  6. Apr 24, 2009 #5

    DaveC426913

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    Re: any more earths???

    Evolution of living organisms is a process that occurs at a snail's pace in human terms. We would not see much in the way of results in the lifetimes of the people involved.
     
  7. Apr 24, 2009 #6
    Re: any more earths???

    Just to pose an idea, would it ever be possible in theory to detonate several nukes on mars to blow it into the goldilocks zone?
     
  8. Apr 24, 2009 #7

    DaveC426913

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    Re: any more earths???

    Nukes wouldn't be the answer, you'd use a method that slow and gradual.

    But the problem is that, Mars at that distance would perturb the Earth's orbit and the two orbit might not be stable.
     
  9. Apr 25, 2009 #8
    Re: any more earths???

    What kind of gradual force would you suggest?
     
  10. Apr 25, 2009 #9

    DaveC426913

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    Re: any more earths???

    We're fantasizing here, right? I mean, we're talking about moving worlds.
    This needs to be stated because PF has an "overly-speculative posts" policy.

    Anyway, you'd do something like this:

    Put a low impulse, long-running engine like an ion engine or VASIMR engine on an asteroid.
    Use the engine to move the asteroid into Mars orbit.
    Move the asteroid using the engine, Mars will follow.

    Read up on "Gravity Tug".
     
  11. Apr 25, 2009 #10
    Re: any more earths???

    The Kepler Mission was recently launched. The goal of this program is to search for earth-like planets in the so called goldilocks zone. However, this would only demonstrate that a particular planet is at the correct distance from it's sun to allow the possibility for organic life to occur on that planet. It would be miles from proof for actual life on that planet.
     
  12. Apr 26, 2009 #11
    Re: any more earths???

    Fantasy of course.

    That's a brilliant idea to use an orbitting asteroid to slowly tug at the planet its orbitting.
     
  13. Apr 27, 2009 #12

    wolram

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    Re: any more earths???

    If you calculate how many particles there are in the U then suppose they can create an Earth the probability comes to zero we are an enigma. the drake equation is just so bogus
     
    Last edited: Apr 27, 2009
  14. May 3, 2009 #13
    Re: any more earths???

    First off I'm not entirely sure what you mean because your grammar is lacking some commas. Secondly, by creating an Earth do you mean a particle for particle verbatim copy of the Earth? Then I would agree, even though I've not done the math, so its merely a gut instinct. But, I would say there is a very high probability that there are many planets very similar to the Earth in size, elemental composition, proximity to star, moon orbits and atmospheric conditions. There are other factors indeed, but in my opinion if you have these basic components mimicing (sp?) the Earth, then the planet would likely host or be suitable for hosting life.

    Where do you get the # of particles in the Universe from? This also assumes a static universe, which we observe as false and it assumes nothing beyond the observational horizon which is a moot point, but still must be lightly considered.
     
  15. Jun 17, 2009 #14
    Why air does not go out of the earth plenit while air pressure is low out side
     
  16. Jun 17, 2009 #15

    HallsofIvy

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    Re: any more earths???

    Gravity! There is no force pulling it away from the earth.
     
  17. Jun 17, 2009 #16

    DaveC426913

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    Re: any more earths???

    There was a SciAm article on this a few years back. If we posit an unending universe, then it is easily calculable how far we'd have to go to find an identical Earth. It was a surprisingly short distance, something like 10^150 metres.
     
  18. Jun 19, 2009 #17
    Re: any more earths???

    You missed an exponent. That was Max Tegmark's paper for SciAm and the minimum he quoted was 10^10^26 metres i.e. a double exponential.
     
  19. Jun 19, 2009 #18

    DaveC426913

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    Re: any more earths???

    OK, that's a little bit farther...:tongue:
     
  20. Aug 19, 2009 #19
    Re: any more earths???

    Life in the galaxy?

    If one surveys stars, and their planetary systems, of 4.5 - 5 Byrs old; and then detects terrestrial exoplanet of say 1.5 earth masses, then one probably still has a magnetosphere - if we are typical (Copernican Principle). And if in habitat zone, then also look for oxygen signature in atmosphere, from very far distance (lyrs). So if photosynthesis for such a long time of 5 Byrs (stromatalites 3.5 Byrs ago for us), then would there be some probability of a species developing culture? Then consider large numbers fall out for our galaxy of 100-200 B stars.
     
  21. Aug 21, 2009 #20
    Re: any more earths???

    Well it sounds like a nice and fuzzy idea but I cringe when people do probabilistic calculations with data sets that are incomplete and admittedly inaccurate. Don't they have better things to do? :)
     
  22. Aug 22, 2009 #21
    Re: any more earths???

    I guess we have been before, philosophizing why the Drake equation is not science, because you can't test it.

    Apart from that, if we don't understand why Venus is the way it is, for instance the lack of spinning and the geology (or Venulogy perhaps?) of 'catastrophic?' resurfacing and extreme high surface temperatures and high thermal gradients of the lithosphere in the past, seem to have little to do with the goldilox zone. If that had happened on Earth then we would not have been here. The Drake equation does not account for that.
     
    Last edited: Aug 22, 2009
  23. Aug 22, 2009 #22

    DaveC426913

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    Re: any more earths???

    It's not probabilistic. It's permutative. And it does set down some preconditions.

    I think the only precondition is that the universe is homogenous and infinite in extent.
    That being the case, there are only a finite number of ways that a volume of space can arrange itself.

    If you have four types of egg (white, brown, double-yolk and speckled) and an infinite plane of eggcups, how many permutatons of the four eggs can you lay down before you run out of unique patterns and must start repeating?

    Now, what if you have 10^60 eggs?

    The answer is a pure mathematical derivation.
     
  24. Aug 22, 2009 #23
    Re: any more earths???

    The calculation is worthless imho, aside from making magazine covers.

    What do you mean by homogenous? As far as I know the Universe does not have a density that can be smoothed over to create an average density that would closely plot the actual density for all the regions of space. Not on a small scale (galaxy size) nor on the grandest scale (entire universe). The fringial regions are dominated by massive quasars, whilst the inter-stellar regions are barren undense regions. You would never expect to find a planet in either of these regions, let alone an Earth like planet.

    I would pull any grant money researching such absurdities. This is not good physics or cosmology imho. Its an armchair calculation done to enshrine oneself into the legacy of being the man who told the world how long it would take before they saw themselves again.

    Also, did he consider the living beings on Earth? How long before I bump into an Earth where you and I are sitting where we are at this moment, etc.?

    Garbage!
     
  25. Aug 22, 2009 #24

    DaveC426913

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    Re: any more earths???

    Of course. : clap clap clap : You should be very pleased with yourself.
    I'm not sure why this is confusing you. Homogenous is pretty straightforward.
    In general, if we were able to examine a region of the universe an arbitrary distance from ourselves, it would on a large scale, be similar. Which means:

    These "fringial regions", do you mean "at the edge of our observable universe"? Are you suggesting that, if we look at the same distance in every direction we will see a different makeup of he universe? Because if you do, the implication of that is that we are at the "centre" of something.


    As for finding a planet in these regions, you are thinkng too small. Massive quasars and undense regions are small-scale deviations - blips - on the scale we're talking about.


    Obviousman strikes again. But you're making it sound like you're seeing with a clarity that noone else is.
    Yes. With the postulate that the universe is infinite and homogenous, the conclusion is that there is an exact duplicate of you, and me, sitting in our very houses.


    It is no more a ridiculous conclusion as, for example, the MWI is as a valid interpretation of quantum mechanics.
     
  26. Sep 2, 2009 #25
    Re: any more earths???

    Wow Dave, I'm not sure why you are berating me. Mr. Obviousman? Clap clap clap? Very childish behaviour Dave, tisk tisk. I didn't pick a fight with you, why are you picking one with me?

    Anyhow, back to adult business... by homogenous, you mean the distribution of galaxies? Or the CMB? Or something else?

    Please no more insults.
     
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