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Thread: Is Earth a failed star?

  1. #31
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    May 2018
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    Quote Originally Posted by Jens View Post
    You asked what is non-mainstream. It might simply be that you are misinformed or are using terminology incorrectly.

    No offense, but people need to start reading more carefully. I was sparing the persons feelings by trying to get on even ground, I even said in the following post that the terminology he was using was mumbo jumbo in the contexts he had given.

  2. #32
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    May 2018
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    I am well aware of what is mainstream and what isn't.

  3. #33
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    Ok, let's stop the side conversation. Thanks,
    At night the stars put on a show for free (Carole King)

    All moderation in purple - The rules

  4. #34
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    The issue seems to be the difference between a "failed" star and a "dying" star, as opposed to not using "star" language at all. If one wishes, one way to frame this issue is to say that any spread out high-mass ball of material is destined, as it loses heat and contracts, to end up as either a "failed star" (if it reaches its quantum mechanical ground state before ever undergoing significant fusion) or a "dead star" (if it does reach fusion, but then runs out of fuel). If one is to use that lens, one says every astrophysical object is currently either a star, a failed star, or a dying/dead star. Someone else might then bemoan the overuse of anthropomorphisms and analogies in place of precise language, but to each his/her own.

  5. #35
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    Wouldn’t it be handy to have a snazzy word that simply means non-star? Then we would have two separate categories of objects: Star types from O1 down; Non-star types from BD to perhaps meteoroids.

    This would let failure to not be an option.
    We know time flies, we just can't see its wings.

  6. #36
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    Dec 2016
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    Quote Originally Posted by Ken G View Post
    If you replace "fusion" with "fission," then your thinking is correct. Note that fusion releases heat from building larger nuclei from smaller ones (like hydrogen into helium in stars), whereas fission releases heat by breaking up very large nuclei (like uranium and plutonium). There isn't hydrogen and helium in Earth's core, and the temperature is not high enough anyway, so it's not so much failing at fusion as it is succeeding at fission.
    I had been thinking about this for a while and it seems that fusion is the more likely of the two to have happened. In order for a earth sized clump of uranium or plutonium to form and then spontaneously start a fission reaction seems out of the ordinary. Look at all the stars that are out there. Are any fission??? Why would fusion only be confined to star formation? Aren't the earth, the sun, and all the planets of our solar system approximately the same age and formed from the same soup.
    Last edited by DaCaptain; 2018-Jun-14 at 10:21 AM.
    I know that I know nothing, so I question everything. - Socrates/Descartes

  7. #37
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    Quote Originally Posted by DaCaptain View Post
    I had been thinking about this for a while and it seems that fusion is the more likely of the two to have happened. In order for a earth sized clump of uranium or plutonium to form and then spontaneously start a fission reaction seems out of the ordinary. Look at all the stars that are out there. Are any fission??? Why would fusion only be confined to star formation? Aren't the earth, the sun, and all the planets of our solar system approximately the same age and formed from the same soup.
    As has been said before, the Earth is not hot enough inside to induce a significant amount of exothermic fusion of light elements, and never has been. In ordinary stars there certainly is radioactive decay of uranium and thorium taking place, but these elements are only on the order of one part in a billion of their total mass, so the contribution to the star's luminosity is negligible. The ample amount of hydrogen fusion is what keeps them hot and stable for a long time. For Earth, where the fusion, if any, is negligible, the decay of uranium and thorium is a significant source of internal heat.

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