Results 1 to 14 of 14

Thread: color of Jupiter's "metallic hydrogen"?

  1. #1
    Join Date
    May 2009
    Location
    42.798928,10.952804
    Posts
    400

    color of Jupiter's "metallic hydrogen"?

    Hello,

    (not considering impurities) high-pressure liquid metallic hydrogen, has some color or is it just a colorless and trasparent fluid like water?

    I'm pretty sure that scientists can emulate it in a laboratory...

    I apologize for my silly middle school question
    Last edited by Barabino; 2019-Apr-14 at 12:21 PM.

  2. #2
    Join Date
    Apr 2007
    Location
    Nowhere (middle)
    Posts
    36,287
    Quote Originally Posted by Barabino View Post
    Hello,

    (not considering impurities) high-pressure liquid metallic hydrogen, has some color or is it just a colorless and trasparent fluid like water?

    I'm pretty sure that scientists can emulate it in a laboratory...

    I apologize for my silly middle school question
    Probably so hot it glows bright white.
    "I'm planning to live forever. So far, that's working perfectly." Steven Wright

  3. #3
    Join Date
    Oct 2005
    Posts
    26,530
    Bear in mind that form of hydrogen is deep inside Jupiter, so we wouldn't see that color anyway-- in case that wasn't clear. And I wouldn't be too sure we can create it in the laboratory, one great thing about astronomy is the scale of what is out there can be vastly far from anything we can do in a lab (both in terms of high pressure, and low pressure for that matter). For example the largest pressure ever achieved in a laboratory is 50 million pounds per square inch, which is only about 1/8 the center of Jupiter.
    Last edited by Ken G; 2019-Apr-14 at 06:01 PM.

  4. #4
    Join Date
    Dec 2004
    Posts
    14,782
    A material's color is the mixture of wavelengths of light
    emitted or reflected from it or transmitted through it.
    Since the metallic hydrogen is covered by thousands of
    miles of other stuff, it would only be able to have color if
    it is transparent, or the stuff sitting immediately on top
    of it is transparent. If it isn't transparent, then no light
    can get to it or pass through it, so the notion of "color"
    doesn't apply in any meaningful way.

    -- Jeff, in Minneapolis

  5. #5
    Join Date
    Mar 2010
    Location
    United Kingdom
    Posts
    7,098
    The only reflectance spectra I can see online for liquid metallic hydrogen look a bit like those for liquid oxygen, from them I'd expect to see a pale blue liquid. But I can't reconcile the graphs I've seen with its metallic state as they all had a low average reflectance (0.2-0.3). I'd expect must higher for a metallic liquid. So not sure.

  6. #6
    Join Date
    May 2009
    Location
    42.798928,10.952804
    Posts
    400
    ok, so it can't be trasparent but it must have a metallic shine - so google images suggests this bag's pale blue color...

    clinique-metallic-blue-pale-leather-pouch-cosmetic-bag-1-2-960-960.jpg
    Last edited by Barabino; 2019-Apr-15 at 02:12 AM.

  7. #7
    Join Date
    Mar 2010
    Location
    United Kingdom
    Posts
    7,098
    My guess would have been more like this dress - but in the absence of anything more scientific to go on it could be either!

  8. #8
    Join Date
    Jun 2005
    Posts
    13,387
    I'm sure it would be very beautiful in the nanosecond before you got crushed into a carbon pudding.
    As above, so below

  9. #9
    Join Date
    Sep 2003
    Location
    The beautiful north coast (Ohio)
    Posts
    48,783
    As some others have said, very high pressure, metallic liquid hydrogen I suspect would have a metallic shine to it. I doubt it would be clear like liquid nitrogen or oxygen; both of those are molecular liquids (N2 or O2), so their valence electrons are tied up in bonding. I've never seen molten lithium, but molten sodium looks much like mercury. I'm not sure if it would look that metallic, but I'm thinking more in that direction.

    However, liquid hydrogen as more commonly found on Earth is probably a clear liquid and looks a lot like liquid nitrogen.

    I found this phase diagram for hydrogen, which distinguishes from liquid H2 and liquid metallic H.

    Last edited by Swift; 2019-Apr-15 at 12:54 PM.
    At night the stars put on a show for free (Carole King)

    All moderation in purple - The rules

  10. #10
    Join Date
    Jun 2003
    Location
    Central Florida.
    Posts
    5,783
    Quote Originally Posted by Shaula View Post
    My guess would have been more like this dress - but in the absence of anything more scientific to go on it could be either!
    Wasn't there some famous internet photograph of a dress that looked blue to half the viewers and brown to to half? You should have used that one!

  11. #11
    Join Date
    May 2007
    Location
    Earth
    Posts
    10,210
    You could ask the authors of this article: https://science.sciencemag.org/content/355/6326/715

    They seemed to have made something pretty close
    Information about American English usage here and here. Floating point issues? Please read this before posting.

    How do things fly? This explains it all.

    Actually they can't: "Heavier-than-air flying machines are impossible." - Lord Kelvin, president, Royal Society, 1895.



  12. #12
    Join Date
    May 2003
    Posts
    6,048
    Since the reflectiveness of metals is tied directly to their conductivity, I'd expect liquid metallic hydrogen to end up looking a good deal like liquid mercury.
    Conserve energy. Commute with the Hamiltonian.

  13. #13
    Join Date
    May 2003
    Posts
    6,048
    Quote Originally Posted by swampyankee View Post
    You could ask the authors of this article: https://science.sciencemag.org/content/355/6326/715
    From that paper, it appears that liquid hydrogen starts out transparent, transitions to black as the pressure increases, and then becomes highly reflective at still higher pressures. And that they considered that reflectivity to be one part of the evidence that they had achieved a metallic state.
    Conserve energy. Commute with the Hamiltonian.

  14. #14
    Join Date
    Sep 2003
    Location
    The beautiful north coast (Ohio)
    Posts
    48,783
    Quote Originally Posted by Grey View Post
    From that paper, it appears that liquid hydrogen starts out transparent, transitions to black as the pressure increases, and then becomes highly reflective at still higher pressures. And that they considered that reflectivity to be one part of the evidence that they had achieved a metallic state.
    I don't about hydrogen for sure, but with a lot of materials, that change from transparent, to black, to metallic, is indicative of a change from a molecular solid with a large band gap, to a semiconductor, to a metal, and this all relates to changes in the band gap with pressure.
    At night the stars put on a show for free (Carole King)

    All moderation in purple - The rules

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •