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Space Science

Heavy Metal Frost on Highlands of Venus? 45

deglr6328 writes "The BBC is reporting that a paper published in the journal Icarus, suggests that the highlands of Venus are covered by a layer of Lead and Bismuth frost. The authors of the paper were looking for a way to explain the anomalous high reflectivity (and corresponding low emissivity) shown at high altitudes in synthetic aperture radar images sent back by the Magellan probe in the early 90's. The study concludes that Venus's lowlands are hot enough (~850F) to partially vaporize these metals into a mist which then condenses back out of the atmosphere to a solid on the surface of the cooler Venusian highlands."
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Heavy Metal Frost on Highlands of Venus?

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  • by Otter ( 3800 ) on Tuesday November 25, 2003 @02:58PM (#7561275) Journal
    "Heavy Metal Frost on Highlands of Venus" would have been a perfect song or album title for some ponderous, pretentious 70's metal band. I can see the cover art already -- move over, Rainbow Rising [lyred.com], this is going on the back of my new denim vest!
  • wow... (Score:3, Funny)

    by dacarr ( 562277 ) on Tuesday November 25, 2003 @03:04PM (#7561352) Homepage Journal
    The landscape must look amazing on this planet. Shame we can't actually live there.
  • from article:
    Detailed calculations, to be published in the journal Icarus, suggest that lead and bismuth are to blame for giving Venus its bright, metallic skin.

    I thought bismuth was the stuff in Pepto Bismol. [pepto-bismol.com]

    Wouldn't Venus appear pink if that were the case?!?

    I will save all the anonymous cowards the trouble:
    Wouldn't that cause Venus to appear black on the radar? Doesn't bismuth belong on Uranus?
    • by dacarr ( 562277 ) on Tuesday November 25, 2003 @03:44PM (#7561762) Homepage Journal
      If it weren't for a minor detail that these guys [everything2.com] are down for the move, I'd link to them.

      Anyway, the active color ingredient in Pepto Bismol and its generic equivalents is, if I'm not mistaken, red food coloring - that, and the active ingredient is bismuth subsalycilate, not pure bismuth, whereas the theory here is that it's bismuth and lead.

  • by G4from128k ( 686170 ) on Tuesday November 25, 2003 @03:33PM (#7561676)
    Add a cheap means of hoisting the goodies from the surface and we have the first interplanetary mining operation. The lead might be especially valuable in space for radiation sheilding. I wonder what other yummy metals (arsenic, gallium, indium, etc.) might be found on the surface? Perhaps an orbital station around Venus might be a good for manufacturing semiconductors or superconductors from freely available materials from the surface.

    Only minor detail ....creating an elevator cable that can handle the high temperatures.
    • by RobertB-DC ( 622190 ) * on Tuesday November 25, 2003 @04:23PM (#7562190) Homepage Journal
      I wonder what other yummy metals (arsenic, gallium, indium, etc.) might be found on the surface?

      I spent a day Googling on that idea a couple of years ago, but didn't come up with much. But you've got to figure that even "trace" amounts of particularly valuable metals would be worth gigabucks -- if there were only a way to get to them.

      Here are the specific elements I found mentioned in the .pdf paper:

      This line is talking about what happens on Earth, but it's probably fair to assume that at least some similar chemistry is going on on Venus:
      Halides and/or chalcogenides of several volatile metals (e.g., Cu, As, Pb, Sb, Bi) occur around terrestrial volcanic vents and fumaroles or are present in volcanic gases (Brackett et al. 1995).

      They're definitely looking for interesting minerals (for those not familiar, Au is gold and Ag is silver):
      The calculations shown in Figures 1 included the elements O, C, N, S, H, Cu, Cl, As, Pb, Tl, Se, Br, F, In, Ag, Sb, I, Bi, and Te. We also considered Zn, Ge, Sn, Cd, Hg, and Au. Approximately 660 compounds of the trace metals were considered.

      Tellurium (Te) isn't considered a major player:
      We therefore conclude tellurium frost cannot be the high dielectric material found in the highlands because of its low abundance and thermodynamic instability.

      Next, they look at Copper (Cu), Lead (Pb), and Bismuth (Bi). I think they're saying that Cu could be found, but the Pb and Bi are what's causing the interesting radar readings:
      Copper condenses over Venus' entire surface as Cu2S (chalcocite) and converts to CuS (covellite) at an altitude of ~19 km. Other condensates that are stable at all elevations (i.e., above ~2.6 km) include Ag2S (acanthite), In2O3 and PbS (galena). Bismuthite (Bi2S3) condenses at an altitude of ~1.6 km and stibnite (Sb2S3) condenses at ~16.6 km. Of these compounds, only galena and bismuthite have both dielectric constants high enough to be interesting (see Table 2) and reasonable abundances.

      Now for the good news! If terrestial volcanoes provide a workable model, some of the really interesting elements (Au, Ag, & co) could be present in trace amounts -- but likely much higher concentrations than found in Earth rocks:
      Near terrestrial fumaroles, lead and bismuth often condense together to form lead, bismuth sulfosalts such as galenobismutite (PbBiS4), lillianite (Pb3BiS6), cannizarite (Pb4Bi5S11), and cosalite (Pb2Bi2S5) (Borodaev et al. 2000, 2001). If present on Venus, these compounds may contain large amounts of Cu, Ag, and Cd, which also form stable condensates at Venusian surface conditions. Several other sulfosalts of the elements Pb, Bi, Cu, Ag, As, and Sb also form as volcanic condensates and cannot be ruled out as the heavy metal frost on Venus.

      And wouldn't the aerospace industry be pleased to find some bonus Titanium (Ti)?
      One of the most puzzling aspects of the highland radar data is that at the highest elevations the dielectric constant drops back to values consistent with bare rock. Some of these summit areas, such as Ovda, Atla, and Beta Regiones, also seem to have a porous surficial deposit with a low dielectric constant (Campbell et al. 1999). The perovskite model for the high dielectric material explains these regions by weathering of perovskite (CaTiO3) to fluorite (CaF2) plus rutile (TiO2) through reaction with HF (g). This reaction produces a significant decrease in volume, leading to an increase in the porosity of the rock (Fegley et al. 1992).

      And just in case all this profit has you shaking your head, here's some pure science:
      We propose that lead condensed in the Venusian highlands is a representative sample of Venusian lead, just as Pb in oceanic sediments is apparently a representative sample for terrestrial lead (Patterson 1956). Therefore, it should be possible to determine the age of Venus by measuring the Pb207/Pb204 and Pb206/Pb204 lead isotopic ratios in the heavy metal frost.

      Cool possibilities, for such a hot planet!
    • Only minor detail ....creating an elevator cable that can handle the high temperatures.

      Diamonds Are Forever, baby.
    • Only minor detail ....creating an elevator cable that can handle the high temperatures.

      Major detail... Venus's day is 225 earth days long. It is spinning far too slowly to support a space elevator that relies on a geosynchronous orbit at the top.

      • Actually, the elevator's center of mass must be in geosynchronous orbit. Seeing as the mass of the cable must be comparable to the mass of whatever is on the end, that puts the center of mass closer to the center of the cable. And wouldn't Venus' longer period of revolution just make the geosynchronous orbit at a larger radius?
      • Major detail... Venus's day is 225 earth days long. It is spinning far too slowly to support a space elevator that relies on a geosynchronous orbit at the top.

        Very good point! How about a spinning space elevator [cmu.edu] . It consists of an orbiting spinning tether. Both ends of the tether dip into the atmosphere and nearly touch the ground at one or more landing points along the equator. While the center of mass of the tether is orbiting at what ever required velocity, the tether is counterrotating with a ti
    • Elevators make it easier but still not dirt cheap to move stuff up. Venus is comparable to earth in mass, rotation period, and size, and probably would be about as cost-effective as the earth elevator ($100/lb at best). Also, the extreme climate. Mining light bodies like asteroids, comets, and moons makes more sense - you don't have to spend anything because they're already "up", and sending them down is free, provided you don't destroy anything.
      • Whoa (Score:3, Interesting)

        Venus has a rotational period of over 200 DAYS. By my calculations, Geostationary orbit is effectively non-existant at around 1.7 billion miles. No elevators for Venus!
    • I wonder what other yummy metals (arsenic, gallium, indium, etc.)

      Yes, I find arsenic goes quite well with fava beans and nice Chianti.

      -
    • Space elevators are cool for places you need to send stuff up without blowing up where it came from, but in the case of uninhabitable venus.. Who cares??

      Just attatch some nuke to the nearest large rock floating in space, calculate the direction it needs to go in to enter the planets gravity, and BAM! The explosion sends the rock careening towards Venus.

      After the big mushroom cloud sends the microscopic sediment into the upper atmosphere, you could swoop it up in giant whale shaped spaceships (since the ai
    • You can't build a space elevator on Venus. With its 5834-hour rotational period, geosynchronous orbit around Venus requires the center of mass of the elevator be far too far from Venus to be practical; the mass would be seriously perturbed by the Sun, Mecury, Earth, and Jupiter.

      Throw in Venus's Earthlike high gravity and harsh environment, and you have the single body in the inner solar system that is hardest to commercially exploit. Mercury and the Moon have decently weak pulls, Mars combines weaker pul
  • Imagine trying to scrape that frost off your windshield in the morning...
  • by Dr. Photo ( 640363 ) on Tuesday November 25, 2003 @04:09PM (#7562034) Journal
    I'm dreaming of a highly-reflective metal frost Christmas
    Just like the ones I used to know...
  • by FFFish ( 7567 ) on Tuesday November 25, 2003 @04:57PM (#7562568) Homepage
    I mean, yah, damp snow is a little heavy. Damp Lead/Bismuth snow, on the other hand -- hoo-boy! Bust a gut out there for sure.
  • Rad. (Score:4, Interesting)

    by Elwood P Dowd ( 16933 ) <judgmentalist@gmail.com> on Tuesday November 25, 2003 @05:23PM (#7562888) Journal
    Bismuth is pretty. [twoguysfossils.com]

    That's a picture of Bismuth that we can grow in labs. I wonder if the atmosphere of Venus produces samples that are even more interesting.
    • Re:Rad. (Score:1, Funny)

      by Anonymous Coward
      Imagine the "snow flakes" made out of bismuth. that would put a dent in your windshield!
    • Uh oh, it looks like intelligent design. Bring out the creationists.

      Seriously, those are pretty amazing crystals. Are these formed naturally?
  • Isn't our planet covered with deposits of frozen metals, too?
    • Hardly. Most of it is oxydized.

      I agree that the frozen metal part is probably the least interesting of this article. I want to see the lead rain/snow down.

FORTRAN is not a flower but a weed -- it is hardy, occasionally blooms, and grows in every computer. -- A.J. Perlis

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