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Earth Science

Where Has All the Xenon Gone? 225

LucidBeast writes "Xenon, the second heaviest of the noble gasses, is only found in trace amounts in the atmosphere. Atmosphere contains less xenon than other lighter noble gasses. Missing xenon has perplexed scientists and it has been speculated that it is hiding in the Earth's mantle. Now, a group at the University of Bayreuth in Germany thinks it might have found the answer. It turns out that xenon does not dissolve easily into magnesium silicate perovskite, and thus it cannot hide there. Because it had no place to hide, it is now gone forever."
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Where Has All the Xenon Gone?

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  • Obligatory (Score:5, Funny)

    by Legion303 ( 97901 ) on Thursday October 11, 2012 @08:34AM (#41618015) Homepage

    Found it! It was in the couch.

  • There is probably a massive government Xenon reserve somewhere, like there is for almost everything else; oil, corn, wheat, your private information, and so on...

  • by Anonymous Coward on Thursday October 11, 2012 @08:35AM (#41618029)

    This will make the Xenonphobes happy.

  • by Anonymous Coward on Thursday October 11, 2012 @08:44AM (#41618075)

    It'll be found in a country that by coincidence is in need of liberating.

  • by Anonymous Coward on Thursday October 11, 2012 @08:46AM (#41618099)

    I'm confused: did it go out into upper atmosphere or space like helium (seems unlikely @~10x weight of nitrogen & oxygen), did alchemists turn it into gold or did we overestimate the amount there initially was? not seeing how the "conservation of mass" loop is being closed here...

    • by gl4ss ( 559668 )

      I'm confused: did it go out into upper atmosphere or space like helium (seems unlikely @~10x weight of nitrogen & oxygen), did alchemists turn it into gold or did we overestimate the amount there initially was? not seeing how the "conservation of mass" loop is being closed here...

      it's assumed it was here after earth formed, by assumptions that the material which earth was formed from had x amount of it.

    • by mcgrew ( 92797 ) * on Thursday October 11, 2012 @09:07AM (#41618303) Homepage Journal

      RTFA. It says that it was probably in the early earth's atmosphere, and the earth's atmosphere was probably blown away by some event, and then re-established itself xenon-free from gasses bubbling up from the molten landscape.

      They also wonder why Mars has no xenon.

    • by Logger ( 9214 ) on Thursday October 11, 2012 @09:12AM (#41618339) Homepage

      I interpreted the poorly written article to mean. The forming rocks could absorb the other noble gases just fine, but not xenon. I infer this would have left an atmosphere (at the time) that was rich in xenon since very little of it was absorbed into the rock. The article speculated that some form of meteorite collision or solar event blew off the atmosphere. Leaving me to infer that the atmosphere we have today is the result of the rock releasing gas into the atmosphere. Since the rock was xenon poor, today's atmosphere is also xenon poor as a result.

  • Wrong question (Score:5, Informative)

    by JazzHarper ( 745403 ) on Thursday October 11, 2012 @08:49AM (#41618115) Journal

    TFS makes no sense at all; TFA is not much better. It seems that, rather than asking, "Why is there so little xenon in the atmosphere" and coming up with a purely speculative answer, the researchers might have questioned why anyone expected to find more.

    • Re:Wrong question (Score:4, Informative)

      by Fubari ( 196373 ) on Thursday October 11, 2012 @09:44AM (#41618653)

      It seems that, rather than asking, "Why is there so little xenon in the atmosphere" and coming up with a purely speculative answer, the researchers might have questioned why anyone expected to find more.

      I thought everyone (well, scientists anyway) expected more Xenon than we observe on Earth because of meteorite samples: apparently meteorites have more xenon than we see in our atmosphere.

      Unless... did you mean why didn't the Bayreuth researches test (e.g. question) any those theories? I thought they did test one of those theories by trying to saturate a mineral (perovskite) with xenon, said mineral being found in the Earth's mantel. (IANAGS, so perhaps an actual geo-scientist could comment on whether perovskite was a good choice for a test like this; I'm willing to give the Bayreuth researchers the benefit of the doubt, given that they are actual geoscientists and probably gave some thought to candidate minerals for their test).

      Interesting? Sure... I never knew about a "xenon discrepancy"; so mildly interesting.
      Informative? Sort of... I would have liked to see another paragraph on xenon comparing content for extra vs. terrestrial rocks. I'm willing to give the geo-scientist community the benefit of the doubt of having thoroughly considered the "xenon deficiency" to the point where they actually gave it a name.

      From TFA:

      “This model is enough to explain the whole xenon deficiency,” says Svyatoslav Shcheka, a geochemist at the University of Bayreuth in Germany. He and Hans Keppler, also of Bayreuth, report the finding online October 10 in Nature.

      Compared with meteorites that formed out of primordial solar system stuff, Earth and Mars have far less xenon in their atmospheres. Scientists have proposed many possible explanations, such as minerals that locked up xenon in the upper parts of Earth’s middle layer, the mantle.

    • I am guessing that there is some pretty solid theory of exactly what radio of material is created in stars and then expelled in when they die. So we know that teh universe is made up of xx% cardon, x% silicon, xx% xenon.
      So any mass as big as a planet would have that same percentage of Xenon unless something happened to it.

  • by srussia ( 884021 ) on Thursday October 11, 2012 @08:50AM (#41618133)
    ...is xenophobic, what hope does mankind have?
  • by rossdee ( 243626 ) on Thursday October 11, 2012 @08:50AM (#41618137)

    They used the Xenon to make XBox 360's

  • Seriously, all new cars come with HIDs now...

    • most new cars I've seen over the past 5-6 years have come with LED headlights. First thing I did when I got the electronics for my bike in 2007 was replace the HIDs with LEDs. They're far more efficient and far more rugged.

      • by dopaz ( 148229 )

        You are mistaken, LED headlights are just now becoming available from the factory. While aftermarket conversion kits may have been available (though I've never heard of anyone else replacing their HID headlights with LEDs) they certainly aren't common.

        One of the first new cars that was equipped from the factory with LED headlights was the 2008 Lexus LS600h. That's the Hybrid version of the flagship Lexus sedan. It is a $100,000+ vehicle and is pretty rare. Five years later, we are starting to see LED he

        • the Caetano coaches that National Express use have LED main beams. They're all at least ten years old, and while the chassis might be built by either Volvo or Renault, the coachwork is all Spain.

          Source: I rode in one yesterday and I'll be riding in one again tonight.

  • So, where did it go?

  • by wonkey_monkey ( 2592601 ) on Thursday October 11, 2012 @09:11AM (#41618329) Homepage
    (please note that this post is aimed more at the editor than the submitter, whose first language may not be English)

    "Xenon, the second heaviest of the noble gasses, is only found in trace amounts in the atmosphere.

    So far so good.

    [The] [a]tmosphere contains less xenon than other lighter noble gasses.

    Could be read as meaning that the other noble gasses contain more xenon than the atmosphere, but as a sentence it's passable.

    ...it is hiding in the earths mantle.

    It's called [the] Earth, and you forgot the possesive apostrophe.

    Now a group at the University of Bayreuth in Germany think that they might have found the answer.

    "The answer," given the context, can only seem to mean that they've found out where the xenon is hiding, but...

    I[t] turns out that xenon does not dissolve easily into magnesium silicate perovskite, thus it cannot hide there. And because it had no place to hide, it is now gone forever."

    Oh, okay, so "the answer" seems to be "we still don't know, but it's not where we thought it was"? Rather than "it is now gone forever" it seems (from reading one of articles, shock horror) that it was never actually there in the first place - perhaps substituting "come from" in place of "hide" would have made more sense.

    Yours sincerely,

    Captain Pedantic

  • Even if it doesn't dissolve in perovsky, it actually dissolves very well in Topatourbiolilepiquorthite [lmgtfy.com]!! So that is not a good reason!
  • Considering their web page hasn't been updated since 1997...
    xenononline.com [xenononline.com]
    ...I'm not surprised they're gone forever.
  • http://en.wikipedia.org/wiki/Noble_gas_compound [wikipedia.org]

    Yes, see the link: of all the noble gases we've studied, it is the most chemically active, we've created many more compounds with xenon than any other noble gas. It's the most reactive.

    Radon is heavier and has more complex electron shells and therefore is probably more reactive, theoretically. But it is also radioactive, so it isn't more chemically active when we take into account the concept the idea of sticking around and staying in the compound.

    So xenon is the most chemically active noble gas, period.

  • Where have all the Cowboy Neals gone?
    Long time passing.
    Where have all the Cowboy Neals gone?
    Long time ago.
    Where have all the Cowboy Neals gone?
    Mommas grounded them one by one.
    Oh, When will they ever learn?
    Oh, When will they ever learn?
  • "Borno, gone relativistic. See you in a hundred years. Xenon."
  • I'd like to say you can't make this up, but, apparently, you can.

  • O Noble Gas, We Hardly Knew Ye! :(

  • after I read the article title:

    I need some Xenon!
    I'm holdin' out for some Xenon 'til the mornin' li-ight!
    ...

    Bad 80s movie? You're soaking in it!
  • ...But, I still don't Xenon.

  • by mister_playboy ( 1474163 ) on Thursday October 11, 2012 @10:43AM (#41619261)

    At 169 m/s, the speed of sound in xenon gas is slower than that in air due to the slower average speed of the heavy xenon atoms compared to nitrogen and oxygen molecules. Hence, xenon lowers the resonant frequencies of the vocal tract when inhaled. This produces a characteristic lowered voice timbre, an effect opposite to the high-timbred voice caused by inhalation of helium. Like helium, xenon does not satisfy the body's need for oxygen. Xenon is both a simple asphyxiant and an anesthetic more powerful than nitrous oxide; consequently, many universities no longer allow the voice stunt as a general chemistry demonstration. As xenon is expensive, the gas sulfur hexafluoride, which is similar to xenon in molecular weight (146 versus 131), is generally used in this stunt, and is an asphyxiant without being anesthetic.

    Fun times. :)

  • I agree with the critics of this model.

    "Other scientists arenâ(TM)t so sure. ChrystÃle Sanloup, a geochemist at the University of Edinburgh, has studied other, shallower places in the Earth where xenon might be locked up. She says the new paper canâ(TM)t explain several aspects of xenon geochemistry, including how Mars could also be lacking xenon in its atmosphere when it has very little perovskite in its depths."

  • In my opinion, Xenon [ipdb.org] was probably the best of the early wave of reactive/interactive (voice synthesis) pinball machines, and it seems impossible to find any around any more. Damn shame.
  • going with Core i3/i5/i7 for their servers, underestimating the advantage of Xeon (support for ECC memory and hence protection from cosmic rays).

Get hold of portable property. -- Charles Dickens, "Great Expectations"

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