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Astronomers Find an Old-Looking Galaxy In the Early Universe

schwit1 tips news that a team of astronomers has studied one of the most distant galaxies ever observed and found puzzling results. The light we're seeing from this galaxy comes from roughly 700 million years after the Big Bang, so on the cosmic scale, it's quite young. But the galaxy appears much older than astronomers expected. Their paper was published today in Nature. At this age it would be expected to display a lack of heavier chemical elements — anything heavier than hydrogen and helium, defined in astronomy as metals. These are produced in the bellies of stars and scattered far and wide once the stars explode or otherwise perish. This process needs to be repeated for many stellar generations to produce a significant abundance of the heavier elements such as carbon, oxygen and nitrogen. Surprisingly, the galaxy A1689-zD1 seemed to be emitting a lot of radiation in the far infrared, indicating that it had already produced many of its stars and significant quantities of metals, and revealed that it not only contained dust, but had a dust-to-gas ratio that was similar to that of much more mature galaxies.

7 of 157 comments (clear)

  1. Quick, make up something dark by cfalcon · · Score: 5, Interesting

    Too much gravity to explain galaxies? 85% of it is dark matter.

    Too little gravity to explain stuff at larger scales and times than that? 70% is dark energy.

    Leaving ~5% as visible matter. If we adjusted our fundamental assumptions by assuming 95% of the universe is everywhere and otherwise undetectable to account for our observations being only 5% predictive, how exact do you think the overarching science really is to begin with?

    IMO we'll need new and better detection techniques to make any real progress- or, if we are stuck with the current level of observations for a couple hundred years, maybe it'll be discerned that way. We just have a lot better luck with the former than the latter.

    1. Re:Quick, make up something dark by Anonymous Coward · · Score: 4, Informative

      The "dark" stuff is essentially a placeholder, its a different way of saying "we don't have the foggiest what is going on heree".

    2. Re:Quick, make up something dark by Anonymous Coward · · Score: 5, Interesting

      we don't know what dark matter is, but we have observed and measured it. we've measured the gravitational effects of dark matter, and their effect on the rotation speed of galaxies in addition to the effects of gravitation lenzing of the (predicted to exist beforehand) dark matter threads between the galaxies. and all those observations are in agreement about how much mass dark matter has.

      so we know quit a bit. just not what kind of particle it is.

  2. Re:Early Universe by MightyMartian · · Score: 4, Informative

    Uh no, the Big Bang explains the ratios of hydrogen, helium and lithium in the observable universe. All the other elements were created when the first stars went supernova. That is rather the point of the nucleosynthesis line of evidence.

    --
    The world's burning. Moped Jesus spotted on I50. Details at 11.
  3. Metals by rossdee · · Score: 5, Funny

    "anything heavier than hydrogen and helium, defined in astronomy as metals."

    The city employee that picks ip the recycling at this astonomers place is not going to be happy///

  4. Hipster galaxy by Neil+Boekend · · Score: 4, Funny

    This hipster galaxy had metals before it was cool.

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    Well, I might have a way, but it only works on a semi spherical planet in a vacuum.
  5. Re:The Big Bang Is Obsolete by Anonymous Coward · · Score: 4, Informative

    Frequency and wavelengths are simply different ways to describe the same thing, periodicity of a wave. They are not "opposite units", just inverse of each other, like resistance and conductivity they describe the same bloody thing and you can convert at will. Look at your first link again, how is that not a perfect match?