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Distant Stellar Explosion Helps Map Universe's Dark Ages 61

Posted by samzenpus
from the in-the-beginning dept.
sciencehabit (1205606) writes "Near the beginning, the universe was without form and void, and darkness was upon the face of the deep. That's because until about a billion years after the big bang, there were no galaxies or stars to illuminate the heavens, which were then filled primarily with neutral hydrogen gas. But a rare ultra–high-energy stellar explosion called a gamma ray burst has offered a new glimpse into this obscure period—the so-called cosmic dark ages—and may help nail down precisely when it ended. A new study of the explosion's afterglow suggests that such neutral hydrogen abounded a billion years after the big bang, so the dark ages weren't quite over then."
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Distant Stellar Explosion Helps Map Universe's Dark Ages

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  • by MrLogic17 (233498) on Monday May 05, 2014 @08:14AM (#46918349) Journal

    Since not everyone went to Sunday School, TFS is referencing Genesis chapter 1 verse 1.

    I'd read you the verse proper, but since verse 2 hasn't been quoted yet, it's too dark to read...

    • by gringer (252588)

      Since not everyone went to Sunday School, TFS is referencing Genesis chapter 1 verse 1.

      I'd read you the verse proper, but since verse 2 hasn't been quoted yet, it's too dark to read...

      You have an off-by-one error. Verses in the bible don't begin at zero.

    • I don't think it was lost on anyone. It's funny because it was an incredibly accurate description of the beginning of time from a document thats nearly 4000 years old, before they even know what stars, time or space were. The concept of "Formless and Void" are incredibly advanced topics for the time period it was written in. We had no concept of "Void" at the time.

      • Of course we had a concept of "Void" at the time, it's written in at least one document from the time (Genesis). There wasn't a numeric symbol for zero, but that doesn't mean there was no concept of emptiness.
      • It's funny because it was an incredibly accurate description of the beginning of time from a document thats nearly 4000 years old, before they even know what stars, time or space were. The concept of "Formless and Void" are incredibly advanced topics for the time period it was written in. We had no concept of "Void" at the time.

        Well, 4000 years ago they didn't say "formless and void" they said "(something in a language that wasn't English)". They only said "formless and void" when the Bible was translated

    • by Cyberax (705495)
      That might sound insightful, but it's not. It's just funny. The first verse means that the Earth was created before the first stars, which is not true. And even the second verse is not correct, as the first moments of the Universe's existence were so bright that it took millions of years for it to cool down to mere 'just hot enough to melt steel' temperature.
      • ...and one could go on and on. Line by line, Genesis is pretty much nonsense, and isn't even particularly good poetry in places where it is poetic. Heaven and Earth first. Darkness on the face of the deep, where from the next sentence it is clear that the "deep" is the waters, that is, the ocean. Then light, which divides light from darkness, with light called day and dark night. Note well that there is still no sun, but there is day and night. Then he creates a "firmament" -- that would be a solid bo

  • by mark-t (151149) <markt@lynx. b c .ca> on Monday May 05, 2014 @08:16AM (#46918363) Journal
    If the universe is 13.8 billion years old, and the universe went through a dark period that was supposedly a billion years long, then why can we detect objects that are as far as 13.3 billion light years away? Shouldn't everything past about 12.8 billion light years be.... well... dark?
    • by wonkey_monkey (2592601) on Monday May 05, 2014 @08:48AM (#46918597) Homepage

      why can we detect objects that are as far as 13.3 billion light years away?

      "...years ago", rather than "light years away," really. The light has taken 13.3 billion light years to get here, but the source was closer than 13.3 billion light years away when the light was emitted, and is further than 13.3 billion lights years now* (by about 3-4 times).

      *for a certain value of "now"

      • by mark-t (151149)
        If the source was closer when the light we are seeing now was emitted, then we should be seeing it now at the distance it was at the time. The objects are, as we see them now on earth, over 13 billion light years away, which means that the light was emitted from them over 13 billion years ago. That doesn't sound particularly dark to me.
        • The objects are, as we see them now on earth, over 13 billion light years away

          I'm not sure you should infer that from the article. All it says is (roughly) when the light was emitted; not how far away the object was at the time.

          The object could have been, say, 5 billion light years away at the time of emission, but the expansion of space means the light has taken 13 billion light years to get here.

          • by mark-t (151149)
            If the object was 5 billion light years away at the time of emission, then it would take 5 billion light years for that light to reach us... not more... even though by the time the light reached us the object would be much further.
            • Spacetime is expanding at a very high rate. In that expansion the light emitted had a larger space to cross in order to get here. Therefor it would take longer for it get here than just the 5bn yrs. I been reading your comments and some of the folks here have been giving you great examples and explaining things perfectly. It is hard to grasp some of this if you are not a Physics/science major. Take a few entry level Physics classes, shit watch the new Cosmos show(or How the Universe Works is a great on
              • by mark-t (151149)
                If something appears 5 billion light years away, then the light that you are seeing from that thing was emitted 5 billion years ago. If something appears to be 13.3 billion light years away, then the light that we are seeing from it was emitted 13.3 billion years ago... which is considerably earlier than the alleged dark period... ended. if things weren't really emitting any light before the dark age came to an end, then why can we detect them?
  • by blue trane (110704) on Monday May 05, 2014 @08:20AM (#46918383) Homepage Journal

    Doesn't the CMB indicate that re-ionisation occured much earlier, with the latest redshift being 7 which is well before a billion years since the Big Bang?

    The discrepancy between CMB measurements and quasar measurements of reionization is presented in Week 5 of Greatest Unsolved Mysteries of the Universe [edx.org].

    • At a redshift of 7 the universe is about 770 Myr old (with either Planck or WMAP 9 cosmology) which is close enough to 1 Gyr that you can say "about a billion years" (I guess it sounds better in a pop. science article).

      I have more of a problem with the line "there were no galaxies or stars to illuminate the heavens". They existed, it's just that the universe was opaque during this period.

  • by rubycodez (864176) on Monday May 05, 2014 @10:09AM (#46919263)

    first stars are 100 million years after big bang, by the time 1 billion years passed galaxies were everywhere

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