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Space Science

Was Earth a Migratory Planet? 257

astroengine writes "Why our planet isn't a "snowball Earth" — a dilemma called the 'faint young sun paradox' — has foxed solar and planetary scientists for decades. Since the Earth's formation, a planet covered in ice should have stifled any kind of greenhouse effect, preventing our atmosphere from warming up and maintaining water in a liquid state. Now, David Minton of Purdue University has come up with a novel solution that, by his own admission, straddles science fact and fiction. Perhaps Earth evolved closer to the Sun and through some gravitational effect, it was pushed to a higher orbit as the Sun grew hotter. But watch out, if this is true, planetary chaos awaits."
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Was Earth a Migratory Planet?

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  • by Anonymous Coward on Wednesday April 18, 2012 @07:34PM (#39729591)
    just so you know, you're a retard.
    Also, CO2 is not a poison.
  • Re:Funny pages (Score:4, Insightful)

    by Guppy06 ( 410832 ) on Wednesday April 18, 2012 @08:00PM (#39729827)

    It makes for fantastic science if you then go on to investigate and describe the miracle. "Oh, wow! How did that happen?"

  • by letherial ( 1302031 ) on Wednesday April 18, 2012 @08:43PM (#39730197)

    That documentary had so many leaps and assumptions that it was hard to follow. Basically, it showed itself as so bias that the worship of beer seemed more important then facts; undermining the very fabricate of truth it tried to create. It makes such a leap that if it wasn't for beer, civilized society would of never been created, but the impossibility of knowing that is really never mentioned. There are more then just one thing that started civilization moving, declaring it all to revolve around beer is ridiculous. What about the wheel, same argument could be made. While i admit beer has a strong place in our history, it is not the end-all-be-all that this documentary tried to make it seem. At least, that was my impression of it; i guess if i was a beer lover, i may of seen it different, or maybe if i would of been interested in the whole thing, i was over a friends house and barley paying attention, so watch it for yourselves.

  • Re:Conclusions... (Score:4, Insightful)

    by rtb61 ( 674572 ) on Wednesday April 18, 2012 @09:17PM (#39730371) Homepage

    In the game of interstellar billiards quite unusual things can happens to planets over time. Slowly moving to higher orbits is not one of them. Interacting with other high gravity masses is, whether it's a object passing through the solar system upon it's own intergalactic trajectory causing a direct change or that object impacting other high gravity masses and causing an indirect change or usual orbits of high gravity masses within a system.

    For decades science has avoided catastrophic based planetary orbits, it makes for messy science but over millions of years in a much more interactive galaxy and universe than originally thought, much to the fear of us tiny rock in space dwellers, catastrophic orbital patterns are all too common.

    Catastrophic orbits of course imply major life extinguishing impacts, that's were the catastrophe part comes in and of course that's why science doesn't like to think about them too much.

    Although it allows the hypothesis of much simpler and more logically planetary development models and those planets out of sequence being treated as just the result of catastrophic interactions, it leaves those scientist with such a gut wrenching sense of impermanence that emotion over rules logic and far more stable convoluted models are preferred.

  • by Dahamma ( 304068 ) on Wednesday April 18, 2012 @11:03PM (#39730903)

    It isn't acidification until you cross neutral.

    Sure it is, just like water going from hot steam to slightly less hot steam is still "cooling". It's all just based on concentration of H+, with "neutral" being a given concentration in pure water. "Acidification" just means that concentration is increasing.

  • by Fluffeh ( 1273756 ) on Thursday April 19, 2012 @02:21AM (#39731517)

    That would make perfect sense that as the sun loses mass the planets drift further away, but the problem is that the size of the sun is driven not only by the mass, but the available fuel driving the fusion reaction inside it. The radius of the sun is maintained by the amount of energy being released in its core through fusion which pushes against the force of gravity pulling the sun together. Certain elements fuse releasing a lot of energy, others fuse releasing only a little energy - yet others fuse and take in energy from their surroundings. The tipping point is Fe (Iron), anything lighter releases energy when it is fused, anything heavier absorbs energy. While sun has converted about 100 earth masses into energy over the 4.5 billion years it has been here, it is still fusing mainly Hydrogen (lots of energy output), meaning that by the time it reaches red giant phase in about another 5.5 billion years, it will have used up a bit over another 100. The problem is that it has around 330,000 times as much as the Earth. It is losing mass through fusion, but not nearly enough to increase the orbital radius of the planets by the time it reaches the red giant phase.

  • by Fluffeh ( 1273756 ) on Thursday April 19, 2012 @02:26AM (#39731537)


    the sun gets about 1% brighter every million

    is wrong. The sun is getting brighter at the rate of 10% every billion [wikipedia.org] years.

    Short and Long [wikipedia.org] scales aside, a billion years is at minimum 1,000 million (or a million million if you use the long scale) - both of which are orders of magnitue different to what you claim.

  • Re:Conclusions... (Score:5, Insightful)

    by Black Parrot ( 19622 ) on Thursday April 19, 2012 @07:12AM (#39732473)

    These "inconvenient truths" prove that there is an intelligent designer of the universe.

    Of course they do. But who is the intelligent designer? There are quite a few candidates so far. And there's also Me. I'll give you 73 virgins in paradise and point to point fiber. In return, you just have to donate a small portion of your savings to My Bank Account.

    You have hit the nail on the head. Religion is a carrot & stick approach to behavior modification, with the clever twist that they want real behavior modification in the here-and-now so your imaginary soul will get the imaginary carrot instead of the imaginary stick in your imaginary afterlife.

    And when we scoff, they offer up Pascal's wager, which is like a stock broker asking you to give real money for stock in an imaginary company - think how rich you'll be if it turns out that the company actually exists!

    Or, since the emphasis is usually on the stick rather than the carrot, it's like a protection racket that asks you for real money to prevent some imaginary thugs from burning down your imaginary soul's imaginary restaurant in your imaginary afterlife.

    Sweet scam. If my current gig doesn't work out, I'm going to start a religion.

  • by spacemandave ( 1231398 ) on Thursday April 19, 2012 @11:25AM (#39734309)
    The problem is not Earth's stability, it's Mercury's. Mercury is close to a so-called secular resonance, and it's eccentricity varies more chaotically than Earth or Venus. So yes, Earth would remain bounded indefinitely as long as Mercury never attains a high enough eccentricity that it begins crossing into Venus's orbit. Once close encounters take place with Mercury, the whole inner solar system can rapidly destabilize.

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