'Electric Earth' Could Explain Planet's Rotation

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'Electric Earth' Could Explain Planet's Rotation

Posted by Soulskill on Saturday January 21, 2012 @08:53AM 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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And that's why by Anonymous Coward · 2012-01-21 08:59 · Score: 2, Funny

That's why I bought a Saturn.
arXiv link by fishicist · 2012-01-21 09:00 · Score: 5, Informative

Full text available on the arXiv, for those without a subscription to PRL: http://arxiv.org/abs/1112.5068
Magnetic field + conductor = Electricity? by atchijov · 2012-01-21 09:01 · Score: 5, Interesting

Is there any electricity flowing and if there is, how can we harvest it?
1. Re:Magnetic field + conductor = Electricity? by NoobixCube · 2012-01-21 09:07 · Score: 5, Insightful
  
  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.
  
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2. Re:Magnetic field + conductor = Electricity? by Ethanol-fueled · 2012-01-21 09:27 · Score: 5, Interesting
  
  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.
3. Re:Magnetic field + conductor = Electricity? by John+Hasler · 2012-01-21 10:06 · Score: 4, Informative
  
  Of course, his work was buried so Edison could make a buck with inferior technology.
  There's a problem with your theory. His name was George Westinghouse.
  
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4. Re:Magnetic field + conductor = Electricity? by AmberBlackCat · 2012-01-21 11:25 · Score: 2
  
  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.
5. Re:Magnetic field + conductor = Electricity? by dak664 · 2012-01-21 13:12 · Score: 5, Informative
  
  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.
6. Re:Magnetic field + conductor = Electricity? by dkf · 2012-01-21 23:03 · Score: 2
  
  The problem with electricity for propellers or turbines is that if there's any sort of resistance to the propeller or turbine (say, goose in the prop or turbine intake), your electrically-powered prop has a pretty good chance of stopping altogether. Gas-powered props/turbines are more likely to continue to operate - you know, V = nRT/P.
  You seem to be confused. Electric motors tend to increase their torque at lower speeds due to reductions in inductive resistance. A bird-strike is more likely to damage the blades than to cause the motor itself to fail. (What's more, there have been a number of fully electric planes built already, and they have been around for years; the problem at the time was making them practical when carrying a large payload. Maybe with the better batteries and motors — areas where there have been significant advances in the past decade — it will be more practical to do this in the future?)
  
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7. Re:Magnetic field + conductor = Electricity? by tragedy · 2012-01-22 13:40 · Score: 2
  
  Well, NYC covers about 790 square kilometers, so that's 790 million square meters. It gets a yearly average of 147.08 watts per square meter of sunlight (this includes nighttime). In January, NY's worst month for solar power, it gets 69.58 watts per square meter. So, that's an average of 116 GW for the average and about 55 GW for the worst month. So, to work on solar power, NYC needs to find a way to turn about 9% of that solar power hitting it to electricity for January numbers or 4.3% for the average. In an area as built up as NYC, that's very doable with conventional photovoltaics.
  Clearly some form of power storage is needed for solar. Battery technology tends to be dirty, insufficient, and require too frequent replacement, even with stationary lead-acid batteries. There are other ways such as melting salt and harvesting the heat for power later, or pumping water uphill to reservoirs and then getting it back with hydrothermal. Another method is to synthesize fuels from the atmosphere and water. Methane is dead easy to make and has the bonus that it can be used in existing infrastructure such as natural gas lines. There are also more complex liquid fuels that can be made and have the bonus that they can be burned in existing gas or diesel engines. Such synthesized fuels are carbon-neutral since all of the CO2 released came from the atmosphere to start with.
  Now, if you want to revise your definition of NYC to just the island of Manhattan, then we're only talking about 87.5 km squared. Take out 4 km squared for Central park and so forth. So 83.5 km squared. So only 12.28 GW average and 5.8 GW in the worst case. Of course, we don't know how your 5 GW figure applies, since you said it was for NYC and that almost always means the whole thing and not just Manhattan Island. There are about 1.65 million people living in Manhattan and average electric power use is about 300 Watts in the US, so that's 495 MW. We'll quadruple it to 2 GW because of other people working there and because of all the businesses there, etc. So, that's 16.28% of the average and 34.48% in the worst month. Even in that case, it's doable with good long term power storage.
  Of course I only wrote this because I bothered thinking about the actual numbers. The first thing I started to write is that you were using a deliberately unreasonable example. NYC is a city. Not only a city, but the most densely populated major city in the US. So, your question is a ridiculous farce. You might as well demand that cities produce all of their own food within their borders. The answer to your question, if it hadn't turned out that NYC gets enough sunlight for its own electrical needs, is that you build solar powerplants somewhere sunny and sparsely populated, then you send the power by transmission line to NYC.
  Now, that approach is may still be necessary for NYC if you need not just electric power, but _all_ power that people use. If you average out all of the power that people use in terms of electricity, transportation, heating, all the power used in manufacturing and transporting and providing the goods and services people buy, etc., as well as all the power used generating and transmitting electricity for end use and mining fossil fuels and all other resources, it actually works out to about 11 kW/person rather than 300 W/person (around 37 times more). Of course, the majority of that usually isn't actually _used_ local to the end user, but rather is used in factories, data centers, mines, refineries, bled out from transmission lines, etc. The point is that, even if you consider all of that power use per person, you can still get all of the power we use from solar. You just have to build huge solar power plants in Arizona and convert the power to the forms you need (such as into synthetic hydrocarbons) and then transmit it over lines and pipe it through pipelines and ship it in tankers, etc.
this is all fine and dandy by circletimessquare · 2012-01-21 09:02 · Score: 5, Insightful

as long as this story doesn't bring out the electric universe trolls

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Not to be confused with.... by tverbeek · 2012-01-21 09:04 · Score: 4, Informative

Not to be confused with the Electric Universe Theory.

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1. Re:Not to be confused with.... by cyberchondriac · 2012-01-21 09:50 · Score: 2
  
  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.
  
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2. Re:Not to be confused with.... by EdIII · 2012-01-21 16:03 · Score: 3, Funny
  
  I switched off when I saw the Lovecraft quote.
  Of course it did. That is a defense mechanism because your mind is to puny to comprehend and/or confront the madness of the abyss......
Iron Monoxide? by Doctor+Morbius · 2012-01-21 09:06 · Score: 5, Informative

FeO is Ferrous Oxide not Iron Monoxide.

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1. Re:Iron Monoxide? by tqk · 2012-01-21 09:16 · Score: 5, Funny
  
  FeO is Ferrous Oxide not Iron Monoxide.
  The topic at the moment is geology, not chemistry. Try to keep up.
  Bloody chemists. Grumble, mumble, ...
  
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2. Re:Iron Monoxide? by Anonymous Coward · 2012-01-21 10:01 · Score: 4, Informative
  
  They are synonyms according to Chemical Book.
3. Re:Iron Monoxide? by istartedi · 2012-01-21 10:41 · Score: 4, Funny
  
  As long as it isn't dihydrogen monoxide. That stuff's dangerous!
  
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4. Re:Iron Monoxide? by LtGordon · 2012-01-21 10:48 · Score: 5, Funny
  
  FeO? That stuff is ugly.
5. Re:Iron Monoxide? by Tacvek · 2012-01-21 12:12 · Score: 4, Informative
  
  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".
  
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6. Re:Iron Monoxide? by Tacvek · 2012-01-21 12:21 · Score: 2
  
  The preferred name would indeed be "iron(II) oxide". The name "iron monoxide" is however correct for a purely stoichiometric name. Such a name does not indicate the exact number of each element in a molecule, only the relative numbers. It also does not indicate the bonding in any way.
  See the IUPAC Red Book 2005 for more details.
  
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7. Re:Iron Monoxide? by Will.Woodhull · 2012-01-21 19:13 · Score: 3, Interesting
  
  "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.
  
  --
  Will
So the takeaway... by Anonymous Coward · 2012-01-21 09:23 · Score: 2, Interesting

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?
Re:Physics Question. by Nidi62 · 2012-01-21 09:49 · Score: 3, Funny

Find a really large sock and see if it stick to the Earth?

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Re:Physics Question. by c++0xFF · 2012-01-21 10:41 · Score: 2

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 Earth to have any net charge, you have to postulate some mechanism for the charges to get separated by cosmological distances.
Communication medium? by zackhugh · 2012-01-21 10:48 · Score: 2

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?
Re:Physics Question. by ceoyoyo · 2012-01-21 10:49 · Score: 2

If Earth had any significant net charge you'd stick to it. Really hard. Much harder than gravity pulls you.
Could explain the _torque_ by mbone · 2012-01-21 11:08 · Score: 2

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...
1. Re:Could explain the _torque_ by Hognoxious · 2012-01-21 12:25 · Score: 4, Funny
  
  inverse mountains
  Downtains?
  
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Re:Was that headline intended to set off the kooks by lister+king+of+smeg · 2012-01-21 12:33 · Score: 2

The scientology troll ate him

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Where did you think the electricity went? by mbstone · 2012-01-21 13:06 · Score: 4, Funny

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.
Hot molten metal can be a battery by fluffy99 · 2012-01-21 15:01 · Score: 2

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