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Mass in galactic halo

  1. Nov 6, 2014 #1

    jim mcnamara

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    I cannot get to the original Science publication to cite it. Science Now has a précis:

    So the information below is not firsthand.

    The claim is that one half of all stars are rogue stars, which are stars which well out into a very large, faint halo around galaxies. The article mentions that previously about 5% of all stars were thought to fall into this category.

    It goes on saying that this finding, if validated, would cause researchers to revisit models of galactic formation.
    Question: why would that cause reevaluation - a lot more previously unaccounted for mass? Does this finding have the potential to invalidate existing estimates of galactic mass?

    Thanks for any comments.
  2. jcsd
  3. Nov 6, 2014 #2


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  4. Nov 7, 2014 #3

    jim mcnamara

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    Thanks for that.
  5. Nov 7, 2014 #4
    From the article it looked more like a reevalution of how the light from these stars would inform on reionization (perhaps makes it even more difficult to understand) and halo size. The latter would have implications for masses and their distribution, I would think. I just scanned the provided paper, and it seems their models are based on LCDM, so presumably no problem there.
  6. Nov 13, 2014 #5


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    Dark matter is the short answer. Without it, nothing makes a whole lot of sense.
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