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B The news media on 2 trillion galaxies: Confused, or am I?

  1. Oct 15, 2016 #1
    Hello. So the last few days there have been articles about how our universe may now contain around 2 trillion galaxies, up from 100-200 billion galaxies that was previously determined.

    But unfortunately I can't make complete sense of the articles I've read, including the one on NASA's site. They seem either inconsistent or unclear. The articles suggest more or less that the 2 trillion number is what it used to be, when there were smaller galaxies and before many merged together to make bigger galaxies, but at the same time they either state the new number in the present tense or simply don't clarify on this point.

    So my questions:
    1. Is 2 trillion galaxies what it should be currently, or simply what it used to be when the universe was younger?
    2. The new discovery still does not imply that there's more ordinary matter than what's already been estimated, or does it?
  2. jcsd
  3. Oct 15, 2016 #2

    Vanadium 50

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    The number of galaxies today is the same as it ever was.
    The average size of galaxies in the distant past was smaller, so there were correspondingly more of them.
  4. Oct 15, 2016 #3
    Thanks for the confirm. That's what I thought . . . Unfortunate that much of the news media was too shallow to want to make that clear.
  5. Oct 15, 2016 #4


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    The lay public is entertained by the numbers, not the technical details.
  6. Oct 15, 2016 #5
    It's a real shame.

    In another sense though, I'm glad. It made me finally get an account here. (Not that this compensates for the lay public's need for information the wrong way.)
    Last edited by a moderator: Oct 15, 2016
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