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Earth Science

'Electric Earth' Could Explain Planet's Rotation 153

Posted by Soulskill
from the thought-it-was-gas-powered dept.
sciencehabit writes "When it comes to Earth's rotation, you might think geophysicists have pretty much everything figured out. Not quite. In order to explain some variations in the way our planet spins, Earth's mantle — the layer of hot, softened rock that lies between the crust and core — must conduct electricity, an ability that the mantle as we know it shouldn't have. Now, a new study (academic paper) finds that iron monoxide, which makes up 9% of the mantle, actually does conduct electricity just like a metal, but only at temperatures and pressures found far beneath the surface."
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'Electric Earth' Could Explain Planet's Rotation

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  • by Anonymous Coward
    That's why I bought a Saturn.
  • arXiv link (Score:5, Informative)

    by fishicist (777318) on Saturday January 21, 2012 @04:00PM (#38776291)
    Full text available on the arXiv, for those without a subscription to PRL: http://arxiv.org/abs/1112.5068 [arxiv.org]
  • by atchijov (527688) on Saturday January 21, 2012 @04:01PM (#38776295)
    Is there any electricity flowing and if there is, how can we harvest it?
    • by NoobixCube (1133473) on Saturday January 21, 2012 @04:07PM (#38776351) Journal

      Electricity is remarkably lazy, and doesn't do anything it isn't forced to do. It will always follow the path of least resistance, and will never flow from a point of lower voltage to higher (that would be like water flowing up hill). If there's electricity flowing, you have to ask what's causing it to flow. What's increasing the voltage between the two points? If you harvest the electricity without unerstanding why it's flowing in the first place, you won't know what the consequences may be.

      • Perhaps the original question could be rephrased to, what can we plug into the mantle that electricity will travel through easier than the mantle itself? But I'd have to wonder, if there is some way to harvest electricity from it, would that have a consequence similar to what harvesting water has done to the Colorado River [wikipedia.org].
        • The Earth's magnetic field rotates some however slow it might be. In theory, energy could be captured through induction. It would be a waste of time and money to do so, but I think it could be done just to prove a point.

        • by drinkypoo (153816)

          I may be about to commit a major nerd faux pas but I think it was Dyson who envisioned wrapping a planet in a coil of wire. You could draw energy from the coil and slow the planet down, or put energy into the coil and speed it up. Unfortunately there's a company called "Dyson Motors" so... sigh. But I thought it was called a "Dyson Motor". Can't find anything. Maybe someone else knows more, or can correct me.

        • by mcgrew (92797) *

          It's probably more like harvesting water from the Pacific Ocean. There is comparatively little water in the Mississippi, let alone the Colorado.

      • by dak664 (1992350) on Saturday January 21, 2012 @08:12PM (#38777749) Journal

        Path of least resistance does not apply to electricity. It follows every field gradient and takes every path as fast as it can. The current through each path is limited by the reduction of the gradient caused by the charge already along the path, a.k.a. resistance.

        • by jamesh (87723)

          Path of least resistance does not apply to electricity. It follows every field gradient and takes every path as fast as it can. The current through each path is limited by the reduction of the gradient caused by the charge already along the path, a.k.a. resistance.

          The "path of least resistance" explanation always bugged me too when I heard it in high school... if it was true, all the electricity in your house (and by extrapolation, your street) would only flow through the appliance with the least resistance and would refuse to flow though all the other appliances, which is clearly not the case.

          The internal resistance of the battery supplying the power might make it look like this is what's happening if you put a very low resistance device in parallel with a higher re

          • V = IR

            For constant voltage, a high resistance will have a low current, and a low resistance will get a high current. If you connect two loads to one constant voltage source (in parallel), the lower resistance (the path of least resistance in this discussion) will get more current. The other gets current also; just less of it.

            That's assuming your source can produce enough current. Using a good thick copper wire to ground an average battery will probably result in a reduced voltage for all loads. And a ho

        • by jbengt (874751)
          Paths of least resistance, then.
    • by Ethanol-fueled (1125189) on Saturday January 21, 2012 @04:27PM (#38776483) Homepage Journal
      Tesla had that all figured out a little less than a century ago.

      Of course, his work was buried so Edison could make a buck with inferior technology.
    • No. Don't even pursue this line of inquiry.

    • by mcgrew (92797) *

      This may or may not be germane (I didn't RTFA but I guess I should), but my dad was an electrical lineman for a lot of companies and did quite a bit of construction on the grid, building towers and stringing high tension cables. A careless lineman building these is in danger of electrocution even before the power is switched on. He would weld his initials on the towers he built by wrapping a 12 gauge wire around the cable and shorting it to the tower.

      He never could figure out what caused it, but when he tol

      • by j-stroy (640921)
        It might have been the difference in potential between ground points.

        My brother was doing some sort of Geo survey work where they ground a wire in a creek and then run it quite a distance to another location for sensing purposes. He told of big static discharges that could really set you down on your ass by contacting the wire once it was at the other location.
  • as long as this story doesn't bring out the electric universe trolls

  • by tverbeek (457094) on Saturday January 21, 2012 @04:04PM (#38776321) Homepage

    Not to be confused with the Electric Universe Theory [holoscience.com].

    • Being unfamiliar with this "theory", I followed the link. Holy hell, do they beat around the bush! I still don't have any idea what they're talking about (other than claiming modern science is deeply fragmented and flawed), but I read enough to decide I don't care.
    • by PopeRatzo (965947) *

      Not to be confused with the Electric Universe Theory.

      I'm a little bit familiar with the Electric Universe Theory and the way some comparative mythologists such as David Talbott and Troy McLachlan have incorporated the Electric Universe into their very interesting work. But I'm not clear on why this story is not connected with the EUT.

      I'm not a physicist or an astronomer, so if you know a little bit about this can you try to clarify? My field was the analysis of texts, so I can deal with the comparative my

      • by tverbeek (457094)

        It's not connected in the same way that the Jimi Hendrix album Electric Ladyland is not connected. By being about something completely different, but it just happens to start with the same word. :)

        • Re: (Score:2, Informative)

          by PopeRatzo (965947) *

          It's not connected in the same way that the Jimi Hendrix album Electric Ladyland is not connected.

          You haven't listened to Electric Ladyland the way I've listened to Electric Ladyland.

          It's connected to everything. Listen to side three after a couple of hits of the orange sunshine and tell me it's not.

          I remember one time, I was out on the back porch of my friend's place up in Wisconsin, and I was staring up at the night sky just as I was peaking and and about halfway through side 3, when "1983... (A Merman

  • Iron Monoxide? (Score:5, Informative)

    by Doctor Morbius (1183601) on Saturday January 21, 2012 @04:06PM (#38776333)
    FeO is Ferrous Oxide not Iron Monoxide.
    • by tqk (413719) <s.keeling@mail.com> on Saturday January 21, 2012 @04:16PM (#38776401)

      FeO is Ferrous Oxide not Iron Monoxide.

      The topic at the moment is geology, not chemistry. Try to keep up.

      Bloody chemists. Grumble, mumble, ...

      • The topic at the moment is geology, not chemistry.

        You mean the history of chemistry. Suffixes like -ous and -ic and prefixes like per- and sesqui- were dropping out of use (i.e. the newer textbooks tended to use Roman numeral in brackets notation) when I last did chemistry twenty-some years ago.

        GP probably still believes in Phlogiston.

        • by yndrd1984 (730475)

          GP probably still believes in Phlogiston

          Phlogiston does exist, it's a nickname for highly entropic kinetic energy.

          • by Whiteox (919863)

            Yep and the AEther in the heavens is dark /matter energy,

            • by yndrd1984 (730475)

              Yep and the AEther in the heavens is dark /matter energy,

              Aether has referred to many different things over the millennia, things we now refer to as dark matter, dark energy, the magnetic permeability of free space, the space-time continuum, and quantum foam. Like phlogiston, the problem was never that these 'aethers' didn't exist, but that they had different properties than people first supposed.

      • Re:Iron Monoxide? (Score:4, Interesting)

        by Will.Woodhull (1038600) <wwoodhull@gmail.com> on Sunday January 22, 2012 @02:13AM (#38779147) Homepage Journal

        "Iron monoxide" is a perfectly cromulent synonym for ferrous oxide.Like dihydrogen monoxide, and hydrogen hydroxide, it is sometimes the better choice for clear communications. Depending of course on exactly what you intend to communicate.

        • by tqk (413719)

          "Iron monoxide" is a perfectly cromulent synonym for ferrous oxide.

          "Rust"?!? Iron-able oxygen?!?

          And in the spirit of your insightful riposte (seriously, honest!), I'd just like to say that was the Scotch talking, not me (and it may still be ...). I don't actually have any quarrels with chemists to speak of. In fact, having known a few, any of them over the age of 35 are damned near miraculous to me. All hail the inventor of the fume hood. And if you want to live to be 40, get out of chemistry. :-)

          Coffee! ...

          • Perhaps it is just the Sunday morning sleepies, but this whole discussion about taking away the legitimacy of ferrous oxide strikes me as ironic.

            • by tqk (413719)

              ... this whole discussion about taking away the legitimacy of ferrous oxide strikes me as ironic.

              Punny! [wiktionary.org] Not much related to chemistry, but still enlightening.

              Puns; gotta love 'em.

    • My CHM 111 professor would get a kick out of this. He's always giving biologists a hard time, but he makes fun of geologists as well.

      Also, I prefer iron(II) oxide personally.
    • Re:Iron Monoxide? (Score:4, Informative)

      by Anonymous Coward on Saturday January 21, 2012 @05:01PM (#38776703)

      They are synonyms according to Chemical Book [chemicalbook.com].

    • by istartedi (132515) on Saturday January 21, 2012 @05:41PM (#38776951) Journal

      As long as it isn't dihydrogen monoxide. That stuff's dangerous!

      • by Ocker3 (1232550)
        I agree, it's been found at the site of every murder commited locally in the last five years, we must do something about this silent killer!
    • by ceoyoyo (59147)

      Iron monoxide would be the modern standardized name.

    • by LtGordon (1421725) on Saturday January 21, 2012 @05:48PM (#38777009)
      FeO? That stuff is ugly.
    • by grcumb (781340)

      FeO is Ferrous Oxide not Iron Monoxide.

      And FeB is Ferrous Bueller. What's your point?

    • Re:Iron Monoxide? (Score:5, Informative)

      by Tacvek (948259) on Saturday January 21, 2012 @07:12PM (#38777457) Journal

      FeO has not been Ferrous Oxide in many years.

      As of the IUPAC Redbook 2005, the preferred name would be "Iron(II) Oxide", however the name "Iron Monoxide" is a valid stoichiometric name for the substance.

      The classic name "Ferrous Oxide" is no longer considered acceptable. I quote from Table III's second definition of the suffix "-ous":

      Ending formerly added to stems of element names to indicate a lower oxidation state, e.g.
      ferrous chloride, cuprous oxide, cerous hydroxide. Such names are no longer acceptable.

      The "-ous" suffix is still permitted as part of acid names like "seleninous acid", or "arsorous acid".

    • According to the IUPAC nomenclature rules (http://www.iupac.org/publications/pac/28/1/0001/pdf/), it is iron(II) oxide.

    • by syousef (465911)

      FeO is Ferrous Oxide not Iron Monoxide.

      More support for my push to rename Hydrogen to Stupidium or Ignoranium. It is the most abundant element after all.

  • So the takeaway... (Score:2, Interesting)

    by Anonymous Coward

    is that, conductivity can be induced in compounds that are normally non-conductive, but only at geologic pressures and temperatures.

    Is it safe to say, in general then, pressure and temperature play a role for conductivity in all non-conductive 'metal'-based compounds?

  • Is there anyway to tell if the Earth is electrically neutral or has a net charge?

    • by Nidi62 (1525137) on Saturday January 21, 2012 @04:49PM (#38776633)
      Find a really large sock and see if it stick to the Earth?
    • Uhm, the Earth is effectively a bar magnet moving through space ==> when you move a magnet you create electricity.
      Therefore there is untapped free electricity.
      QED.

      • Re: (Score:1, Informative)

        by Anonymous Coward
        The problem is you need a circuit to tap that "free" electricty. And guess what? That circuit will be a conductor equally moving through space at the same time. Therefore, potential difference = 0. QED.

        Why are there SO many scientifically illiterate people on Slashdot? Is it because programming is neither science nor engineering, but depends on both to exist?

      • A brilliant answer. Pity it has nothing to do with the question.

      • by Tim C (15259)
        Uh, no - expose a conductor to a changing magnetic field and you generate an electric current within the conductor (which will need to be part of a circuit for the current to flow, etc).

        In other words, just waving a magnet around achieves nothing without a conductor there in which to generate the current.
    • by c++0xFF (1758032)

      One thing we do know is the force from any net charge on the Earth is completely overwhelmed by gravity, the weakest of the fundamental forces. Remember, electromagnetism is about 10^36 times stronger than gravity. This would make detection very hard, indeed, but also suggests that any net charge is very small.

      Now, I'm no cosmologist, but my understanding is that current theories require that the universe itself be electrically neutral (but I don't know why this has to be true, personally). So, for the E

      • by tragedy (27079)

        Good point, because, after all, magnetism can compress matter to such a degree that the cumulative magnetic field strength is so high that even gravity can't escape... Oh, wait, I have that backwards, it's the other way around.

    • by ceoyoyo (59147)

      If Earth had any significant net charge you'd stick to it. Really hard. Much harder than gravity pulls you.

      • Only if I had a significant charge.

      • Doesn't that rest on the assumption that neither you, nor any of your ancestors, nor anything you or they ate, had made electrical contact with the Earth?

      • If Earth had any significant net charge you'd stick to it. Really hard. Much harder than gravity pulls you.

        Actually, if the Earth had a significant net charge, everything in electrical contact with the Earth (like you and me) would have close to the same potential. The Earth would repel us, not attract us.

  • My understanding is that the problem with measuring conductivity on materials heated in a diamond-anvil cell is that you have a central spot that is extremely hot, and then a steep temperature gradient to the rest of the material. Measuring conductivity on a diamond-anvil cell often results in simply measuring the circuit formed in these surrounding boundary areas. It's a pity people are still breaking diamonds with these things rather than thinking about the ramifications the test setup has for their measu
  • Satellites are great, but because of the ionosphere, it would be better to send terrestrial messages through the mantle. Can signals be reliably transmitted and received?

  • by Anonymous Coward

    In 1895 Tesla was harnessing the electrical conductivity of the earth. From Wikipedia:
    A "world system" for "the transmission of electrical energy without wires" that depends upon the electrical conductivity of the earth was proposed, in which transmission in various natural media with current that passes between the two points are used to power devices. In a practical wireless energy transmission system using this principle, a high-power ultraviolet beam might be used to form a vertical ionized channel in

    • No. He was conducting electromagnetic waves through the athmosphere. Electric conductivity is a completely diffferent thing.

      You can't even have the same material conducting both electromagnetic waves and electricity.

  • by mbone (558574) on Saturday January 21, 2012 @06:08PM (#38777149)

    The issue is not really the source of the long-period "decade" fluctuations in the length of the day (LOD). It has been known for decades that these have to be caused by "weather" (fluid magnetohydrodynamics) in the liquid outer core. Has to be, as there is no other suitable source of angular momentum. The atmosphere and oceans up here on the surface simply fall short, by as much as an order of magnitude, and nothing else (ice, groundwater, tectonics, etc.) can even match them. The "weather" in the core is dynamically rather different than the weather up here - the heat source is radioactivity and precipitation of solid iron, while the core is quite conductive, and so the dynamics are MHD, not just HD. We don't know much about fluid motions in the core, but we do know that they have to exist, to drive the observed LOD variations (and also drive the observed changes in the geomagnetic field).

    What the real question is is the nature of the torque between the mantle and the core. The two leading contenders are pressure torques (differences in pressure across whatever inverse mountains there are at the core mantle boundary) and electromagnetic torques. The E&M torques would be enhanced if the mantle is conducting.

    So, this is a plus for the E&M torque theorists, but I wouldn't expect this issue to be really resolved for some centuries, if not longer. The core is not that far away, but it's hard to see through thousands of kilometers of rock...

    • by Hognoxious (631665) on Saturday January 21, 2012 @07:25PM (#38777551) Homepage Journal

      inverse mountains

      Downtains?

      • Downtain Abbeys?
        • I don't think Nietzsche[1] was a Russian, but when you gaze into Abbeys the Abbeys gaze into YOU!!!

          [1] Maybe I'm thinking of Poincaré. I always get them confused because one of them is next to each other in the dictionary.

          • by RockDoctor (15477)

            I don't think Nietzsche[1] was a Russian

            Nyet, she's Deutsch.

            but when you gaze into Abbeys the Abbeys gaze into YOU!!!

            I read that as "the Abbess gauzes into you", and shuddered. Not, it should be said, in anticipation. Or hope.

            [1] Maybe I'm thinking of Poincaré. I always get them confused because one of them is next to each other in the dictionary.

            Huh? Oh, I see. "confused" and "conjecture".

            Time to go and swat a church.

  • by mbstone (457308) on Saturday January 21, 2012 @08:06PM (#38777715)

    One side of every electrical circuit is connected to a cold water pipe. And all the cold water pipes are connected to the earth's mantle. This is why there is electricity in the earth's mantle. The solution? Just connect your circuits to an antenna instead of grounding them. This way all the electrons will be radiated into the ionosphere, and you'll once again be able to touch the earth's mantle without getting a nasty shock.

  • by fluffy99 (870997) on Saturday January 21, 2012 @10:01PM (#38778305)

    It's already been shown that molten metals and rocks in layers can be charged like batteries. Is it no surprise that they conduct? http://www.popsci.com/technology/article/2010-04/molten-metal-batteries-could-store-extra-juice-power-grid [popsci.com]

  • most of the earth... a fluid that could conduct electricity.... sort of like salt water.

  • I wonder if there is some interesting repercussions on this as a way to restart their magnetic sphere. Perhaps it would be possible to pass electricity through its core and get a field.
  • But what is the carbon footprint of all this electricity that Earth is using? Surely that can't be good. We need a treaty with the other planets that curtails Earth's inordinate use of the universe's electricity! Why, it just might throw the interstellar ecosystem out of balance unless we get it under control!

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