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Space Science

Nanodiamonds Are Not Forever 25

Posted by michael from the debeers-disappointed dept.
An anonymous reader writes "Livermore Labs and the Belgian Institute of Astrophysics (Catholic University, Leuven) are reporting today that nanodiamonds trapped by U2 spyplanes are pretty common (one part per 1000 in meteors), but don't originate from violent supernovae as previously thought. Instead their absence in comets suggest they formed after our solar system (are not pre-solar) by chemical vapor deposition -- and from much less violent asteroid collisions. Their technique of spectroscopy is compared to looking for the proverbial needle in a haystack by burning down the haystack. It seems these diamond time capsules are close to perfect tracers for guessing the initial conditions when life first formed in the universe. On April 23-24, a large flux of identifiable comet dust will streak through our stratosphere from the Grigg-Skjellerup earth-crossing dust trail."
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Nanodiamonds Are Not Forever More

Nanodiamonds Are Not Forever

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  • IN SOVIET RUSSIA, the stratosphere will streak through a lorge flux of Comet Dust from the Grig Skejellerup earth-crossing dust trail on YOU!

  • i may just be dumb, but how does a U2 spyplane "trap" these nanodiamonds that are 3 nanometers across...?

    • Re:"trapped"? (Score:3, Informative)

      by jericho4.0 ( 565125 )
      IIRC, it uses a super-low density foam type material, that it simply exposes to the atmosphere when it gets really high. The assumption being, of course, that any dust and stuff captured is on its way down, not up.

    • I'd assume it goes something like this:

      1. U2 spyplane is flying through the stratosphere more or less horizontally.
      2. Space dust is falling through the stratosphere more or less vertically.
      3. Paths of plane and space dust intersect.
      4. Space dust particles, being in general much smaller than a U2 spyplane*, stick to the plane rather than the other way around.

      *) If the dust particles are large enough, however, it is possible for the plane, or at least pieces of it, to stick to the particle as it plummets towards

  • Diamonds are not worth anything. (Score:5, Interesting)

    by Anonymous Coward on Wednesday March 05, 2003 @06:47PM (#5444782)

    On a diamond-related note:

    As this article in The Atlantic [theatlantic.com] ("Have you ever tried to sell a diamond?") points out - diamonds are only perceived to be worth anything because of the diamond cartel.

    In the marketing coup of the century they've managed to convince the world that diamonds are rare and precious - both of which are completely untrue. Think about that the next time you hear "diamonds are forever" - it's advertising propaganda that people have been brainwashed into believing is true.

    • You are 100% correct about perceptions and cartels. Daimonds, Cinderalla and Barbie are three of the most successful con-jobs in history.

      However, If your girlfriend says something along the lines of "Buy be something expensive and useless" ... Don't go signing her up for radiation therapy.

      You know what she wants. And you're going to be paying (too much) for it.

      (Apologies to Emo).

    • The article you quote is over 20 years old.

      Has anyone any more up-to-date information? Like, did the predictions the article made about the mid-80s come true?

    • And they're getting cheaper (Score:4, Informative)

      by Animats ( 122034 ) on Friday March 07, 2003 @05:04AM (#5457225) Homepage
      Synthetic diamonds have been around for about fifty years, and most industrial diamonds are now synthetic. Synthetic gemstones were produced by General Electric in the 1950s, but you had to tie up a big press for days, which made them more expensive than natural ones. But around 1990, better processes for manufacturing diamonds were developed, and synthetic diamond gemstones are being produced in quantity. The diamond industry is trying to create the illusion that the synthetic ones are less valuable (and struggling to develop reliable tests for distinguishing them) but that may be a losing battle.

      Sapphires and rubies got clobbered in the 1970s, when processes for making them were discovered. Linde Chemical introduced the "Linde Star", a perfect star sapphire, and manufactured them in volume, which killed the gem market. Today, you can buy sapphire and ruby bar stock, and it's not expensive. You can buy a 9" long x 0.125 diam. ruby rod on Ebay for $28.88 [ebay.com] Sapphire, because it's used for semiconductors, is produced in high volume as large-diameter bar stock. When you see something like this:

      • We can currently supply sapphire ingots, blanks, windows and wafers up to 200 mm in diameter, bar stock up to 100 mm square and ribbons up to 80 mm wide. All sapphire products are available in stages ranging from raw through polished for epitaxial growth. With six grades of synthetic sapphire, Maintech is sure to meet needs of the customers. Processors and end users now have an opportunity to take advantage of extraordinary prices from Maintech, Inc. [maintechsapphires.com] Normal turnaround time is FOUR WEEKS!
      you know that it's not a valuable, rare gem any more. It's more like Napoleon's rare, expensive set of aluminum dinnerware in the 1700s.

      It looks like something similar is starting to happen to diamonds. Don't put your money in them.

  • hmmm (Score:1)

    by eieken ( 635333 )
    They should check to make sure its not nano-moissanite..
  • ... is what you get if you remove the syllable na from the headline.

  • Carbon and CVD (Score:4, Insightful)

    by reverseengineer ( 580922 ) on Thursday March 06, 2003 @04:25AM (#5447625)
    The conclusions in this article make a lot of sense actually- the conditions in the solar system are in many ways similar to a chemical vapor deposition setup- very low pressure, almost no oxygen, and yet still plenty of material to use as both a vapor (carbon) and substrate (asteroids, comets, dust motes, etc.). I'd expect that these nanodiamonds are simply the result of carbon atoms coming together and clustering on a surface, with the carbon of course in conditions suitable for diamond formation. I would expect that nanoscale clusters of the other carbon allotropes, graphite and fullerenes, should be found in abundance in the asteroid belt as well.
  • Given enough time (heat will speed things up), the crystal structure in diamonds reverts to plain old graphite.

    http://www.bris.ac.uk/Depts/Chemistry/MOTM/diamo nd /diamond.htm

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