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Earth's Core Spins Faster than Earth 309

Dreamwalkerofyore writes "The New York Times has an article on a recent affirmation that the earth's core rotates faster than the earth proper. From the article: 'Confirming assertions first made in 1996, a team of geophysicists are presenting data in the journal Science today showing that the earth's inner core... spins faster than the rest of the planet. Over a period of 700 to 1,200 years, the inner core appears to make one full extra spin. That extra spin could give scientists information about how the earth generates its magnetic field.'"
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Earth's Core Spins Faster than Earth

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  • by kzinti ( 9651 ) * on Friday August 26, 2005 @06:56AM (#13406205) Homepage Journal
    So I'm just wondering: does this delta-omega have anything to do with the fact that the Earth's magnetic field reverses itself every 200,000 years or so [space.com]? Please begin rampant conjecture and wild speculation. Extra credit to anyone who can credibly bring Roswell or right-wing conspiracies into the discussion. Fnord.
    • by aussie_a ( 778472 ) on Friday August 26, 2005 @07:21AM (#13406355) Journal
      So I'm just wondering: does this delta-omega have anything to do with the fact that the Earth's magnetic field reverses itself every 200,000 years or so?

      Well, according to Wikipedia [wikipedia.org] why the reversal happens isn't well understood, so it very well could be. However there are some hints that this is the case in the Geomagnetic excursion page [wikipedia.org]:
      The dominant theory is that they are an inherent aspect of the dynamo processes that maintain the Earth's magnetic field. In computer simulations, it is observed that magnetic field lines can sometimes become tangled and disorganized through the chaotic motions of liquid metal in the Earth's core
      I'd suggest looking for more authorative sources if you're truly interested.

      Please begin rampant conjecture and wild speculation.

      Don't mind if I do. From Geomagnetic reversal at wikipedia [wikipedia.org]:
      homo erectus and their ancestors certainly survived many previous reversals. There is no uncontested evidence that a magnetic field reversal has ever caused any biological extinctions.
      Makes me wonder how geomagnetic reversals coincide with the speciation and evolution of our ancestors (or any animals). The extra radiation might not have killed them, but it certainly could have mixed things up, create higher then normal mutation rates. The last one was 780,000 years ago. Homo sapiens sapiens hasn't ever existed while there's been a geomagnetic reversal. It could be that by the time we came around, the mutations had died down to a normal rate.
    • Please begin rampant conjecture and wild speculation.

      Now someone needs to create a worm-like vehicle capable of transporting nuc-u-lar weapons to the core to get it spinning at the correct rate!

      Forget the space station... take a $1billion ride to THE CORE!!!
    • by deop4s ( 885078 ) on Friday August 26, 2005 @07:56AM (#13406547)
      Probably something - what will be interesting is if someone can figure out not only the speed, but also the direction of the spin. There's no guarantee that the inner core is actually spinning along the same axis as the mantle/crust. Seems possible that an offset of a few minutes between the axes of rotation might explain why the magnetic poles are not exactly matched with the rotation axis of the earth.
      • Not forgetting any precession [wikipedia.org] that may be happening as well. Then there are going to be all sorts of interesting oscillation patterns.
      • by Ungrounded Lightning ( 62228 ) on Friday August 26, 2005 @12:14PM (#13409094) Journal
        what will be interesting is if someone can figure out not only the speed, but also the direction of the spin. There's no guarantee that the inner core is actually spinning along the same axis as the mantle/crust.

        Sure there is: Fluid Friction. Only convection (like atmospheric or oceanic weather phenomena but at geologic time scales) and forces from the dynamo are likely to have any non-straightforward effect, and those will be minor deltas.

        The basic mechanism is obvious: The planet is spinning. The core is molten while the crust is essentially solid. There is a massive moon, orbiting above synchronous orbit and creating tidal drag. The tidal drag slows the rotation and raises the moon's orbit. The tidal braking force is strongest at or near the surface of the planet and vanishes at the center.

        With braking at the outer layers the core spins a tad faster, but in the same direction and (with the braking very small compared to the fluid fricton) ALMOST exactly at the same rate - the difference is about one turn in 300,000 (assuming the middle of the article's range).
    • by maxwell demon ( 590494 ) on Friday August 26, 2005 @08:04AM (#13406631) Journal
      Ok, let's start the pseudo-science and conspiracy theory generator :-)

      Well, you know, in Rosswell there's a dark energy vortex, which extents to the core. This BTW is why the alien space ship crashed; it's quite unusual to have dark energy vortices on earth-like planets (it's not that unusual on gas planets, for example the Great Red Spot is in reality the result of a - much bigger - dark energy vortex [don't believe the scientist telling you it's just a big storm!]), therefore the aliens were not prepared to it. Indeed Earth is quite special to have a particularly rich dark energy vortex structure (a rather big one is e.g. at the Bermuda triangle, although that one reaches a few hundred kilometers into the air, instead going down), which is also the cause of earth rays (water just acts as focus lense for them).

      Now the delta-omega in conjunction with the other periodic effects from sun and moon causes certain structures of the core to coincide with the vortex axis about every 200,000 years. This results in a temporary slowdown of the core (the rotation energy gets transferred into the vortex during that time, and then back into the core to let it spin again). This slowdown lets the magnetic field vanish. Now the time of this breakdown happens to coincide with half a period of the vortex' intrinsic oszillation, therefore when the magnetic field is re-built, it points into the opposite direction.

      Ok, where do the right-wing conspiracies come in? Well, the knowledge of this is actually held back by the right-wing politicians because the dark energy vortex interacts with the carbon dioxide in the atmosphere. Now the increasing level of CO2 might cause the vortex to move, and secret calculations show that in doing so it would permanently kill the rotation of the core and therefore destroy the magnetic field of the Earth. In order to avoid any danger to the oil sales, right-wing politicians actively suppress this knowled... wait, why are those black helicopters in front of my ... NO CARRIER
    • by Smidge204 ( 605297 ) on Friday August 26, 2005 @08:11AM (#13406698) Journal
      Dear kzinti;

      Current scientific theories on this subject are, at best, incomplete. I would like to offer an equally plausible alternative theory; Intelligent Spinning.

      The Intelligent Spinner carefully regulates the speed at which the Earth's inner core rotates relative to the crust, thus regulating with great accuracy the strength and shape of the Earth's protective magnetic shield. Since this shield is so vital to life on this planet, it is inconceivable that it exists merely by chance. Therefore, we can conclude that the Intelligent Spinner was put in place by the Intelligent Designer, as one of the many mechanisms to protect His creation.

      Extrapolating from this scenario, we arrive at the conclusion that the magnetic field reversal is all part of the Intelligent Designer's plan. Indeed, so-called "scientific" estimates have failed to predict another reversal. The Science-agenda advocates would have you believe that such reversals occur every 200,000 years, however in the same breath they also claim it has been over 780,000 years since the previous one. It is apparent that these scientists are simply making excuses for their flawed theories. Indeed, as we all know the Earth is only about 6,000 years old so the very notion of a 200,000 year cycle is absurd! My Intelligent Spinner theory predicts that the magnetic poles has (and will) weaken and eventually flip whenever the Intelligent Designer deems the time is right.

      As you can see, my alternative theory explains the observed natural phenomena just as well as -- indeed, better than -- the current "scientific" theories of geology. I therefore assert that my theory is at least a viable alternative and feel that equal time should be given to its teaching in the classroom.

      Thank you for your time;
      =Smidge=
      • by Beale ( 676138 ) on Friday August 26, 2005 @09:17AM (#13407313)
        This is just one example of the work of the Flying Spaghetti Monster in his Harlem Globetrotter aspect.

        May we be forever touched by his noodly appendage.
      • (Score:5, Insightful)

        *facepalms* Ah, Merton [wikipedia.org], you tricky bastard!

        =Smidge=
      • There is a God (Score:4, Insightful)

        by Urusai ( 865560 ) on Friday August 26, 2005 @09:35AM (#13407475)
        Some people doubt the existence of God, but I propose a doctrine of Intelligent Deogenesis. By postulating the existence of a creator who created God, we can account for the Intelligent Design in the characteristics of God Himself. Clearly, a being of God's infinite intelligence is the product of a being of intelligence. Theories that God evolved from monkeys or one-celled organisms fail the BS test, since God is clearly irreducible in his complexity. God simply sprang fully-formed from the mind of Man. Cogito ergo sum, lorem ipso dolor, quid pro quo, alea jacta est, et cetera.
    • by crovira ( 10242 ) on Friday August 26, 2005 @08:15AM (#13406727) Homepage
      There's a threshold where the fields around the rotor get disorganized (expect geomagnetic migrations to get all screwed up,) and then field lines reverse as the threshold is crossed.

      Nothing actually happens to the rotor (it doesn't spin backwards all of a sudden) but the field lines generated are inverted.
    • Maybe, It's like the spoked rims on a pimped ride. When it spins forward really fast it appears to be spinning backward. So perhaps, millions of years ago, It was spinning VERY fast... So fast that the magnetic field lines appeared (and affected) backward from the flow. And then when the flow slowed, the field normalized. And so on, until we get our current rates.
    • "...and if you bother us again I shall visit you in the small hours of the night and put a bat up your nightdress!"
  • by Ann Elk ( 668880 ) on Friday August 26, 2005 @06:57AM (#13406218)

    The core spins faster because the bodies of the US founding fathers are spinning in their graves at such high RPM.

    • Really, we don't need oil - we need to hook up a generator to Benjamin Franklin, Thomas Paine, and George Mason!
    • by Junior J. Junior III ( 192702 ) on Friday August 26, 2005 @07:18AM (#13406340) Homepage
      No, it's clearly intelligent spin. There must be some agent of unimaginable power who is actively pushing the core to faster velocities. We cannot know why someone would want to do this, but as they must be very intelligent to figure out a way to accomplish this, we must conclude that they have their reasons.

      Now, the real question in my mind, is the intelligent spinner Vulcan/Hephaestus, YHWH, or the Flying Spaghetti Monster [venganza.org]?

      My theory is that it's the FSM. While Vulcan and Hephaestus were gods of the earth and of volcanoes, they were only minor characters in the Olympian pantheon, and on top of that, cripples. Clearly they are incapable of pushing the Earth's core at all. YHWH is too busy turning homosexuals into pillars of salt to be bothered with core spinning. Therefore, only a noodley appendage can spin the Earth's Core at such a velocity.

    • > The core spins faster because the bodies of the US founding fathers are spinning in their graves at such high RPM.

      Hell, even Ronald Reagan is starting to rotate a bit.

      • Hell, even Ronald Reagan is starting to rotate a bit.

        True story, in an interview with Reason, Reagan took the following stances (these are direct quotes):
        1. "I don't believe in a government that protects us from ourselves."
        2. "If you analyze it I believe the very heart and soul of conservatism is libertarianism."
        3. "I disagree completely when government says that because of the number of head injuries from accidents with motorcycles that he should be forced to wear a helmet. I happen to think he's stupid if
  • by Kawahee ( 901497 )
    I don't see how this could be all that technologically useful for consumers, but for the military, I'd like to see little plastic spheres that, when twisted, generate their own little magnetic fields without any other materials than what the enemy would expect to be naturally residing in an area. Drop a few around a desert or combat area, and watch their compasses/electrical equipment go out.
    • by Anonymous Coward on Friday August 26, 2005 @07:01AM (#13406243)
      If we could cheaply generate fields that strong, we would not need nuclear power plants, we could generate all the energy we need using induction.

    • > I don't see how this could be all that technologically useful for consumers, but for the military

      I'm more interested in its effect on my pool game.

    • You'd have to generate an awesome magnetic field to disrupt electronic equipment, if that is even possible. Consider what happens when you have a magnet near a computer: magnetic media get corrupted, and CRT tubes go wonky as the beam is deflected, but otherwise they'll continue to function normally.

      Compasses are a bit easier, but won't be used as much now that GPS is here.
  • Complete? (Score:5, Funny)

    by Boronx ( 228853 ) <evonreis@mohr-e n g i n e e r i ng.com> on Friday August 26, 2005 @06:58AM (#13406229) Homepage Journal
    Whoah, it looks like it's going to complete one full spin in the next decade, that's going to make Y2K look like a walk in the park.
  • Hmmm... (Score:5, Interesting)

    by gowen ( 141411 ) <gwowen@gmail.com> on Friday August 26, 2005 @06:58AM (#13406232) Homepage Journal
    Given that the Earth's rotation is slowing down, isn't it immediately apparent that the liquid core must spin faster than the outside. It's just basic fluid dynamics. If apply a torque to the outside of a fluid filled region, the middle of that region will feel the effect last.
    • by leuk_he ( 194174 )
      And what is causing the spin-down? Is it friction against empty space?
      If it is gravitation from other bodies? I would think this would affect the entire earth, not just the outer part of the earth(you can not shield gravitation. )

      You can say that tidal friction causes this, but wouldn't the same gravity of the moon create tides in the flowing lava?
      • You can say that tidal friction causes this, but wouldn't the same gravity of the moon create tides in the flowing lava?

        Of course they do. The whole planet is slightly deformed.

        Tidal friction has also slowed down the moon rotation so much that it now shows us the same side all the time.
    • Re: Hmmm... (Score:4, Funny)

      by Black Parrot ( 19622 ) on Friday August 26, 2005 @08:19AM (#13406753)


      > Given that the Earth's rotation is slowing down, isn't it immediately apparent that the liquid core must spin faster than the outside. It's just basic fluid dynamics. If apply a torque to the outside of a fluid filled region, the middle of that region will feel the effect last.

      At noon let's all face west and run five miles real fast, to see if we can get the shell back up to speed.

    • by gr8_phk ( 621180 )
      Every time a heavy chunk of crust breaks free and sinks into the liquid, it's like the skater pulling their arms in - it spins faster. Momentum is conserved, but at the shorter radius this translates into higher angular velocity. All the heavy stuff is in the center, and it must have spun up when that first happened. Is the difference still there, or is the process still happening a little bit?
      • Except that the crust isn't heavier than the stuff in the middle. Earth has already mostly differentiated by desnity. (Iron IS the dense stuff.) The crust is basically the lowest density rocky bits, the scum on the top if you will.

        So if the crust broke off and fell inward (for reasons unclear), it would force a denser bit UP and actually slow our rotation.
    • Re:Hmmm... (Score:3, Interesting)

      by Thagg ( 9904 )
      And what's potentially going to be *really* interesting is that earth is going to slow down fairly dramatically over the next few hundred years, according to US scientists. Note the article a few days ago in Slashdot [slashdot.org] about the US government lobbying to get rid of the leap second, and just have a leap hour every 500 or 600 years. If you do the (very simple) math, you can see that these scientists anticipate the earth rotation rate slowing down by five or six seconds a year over that time.

      My guess is that t
      • The expansion of the oceans due to global warming will raise sea level a few meters. Tens of meters, tops.

        Compared to Earth's radius (6378 km), that's chump change. Particularly when you consider that the interior of the Earth isn't going to warm up and will therefore not adjust at all, and that's where the overwelming majority of Earth's mass is.

        Also, note that adding a leap hour every 500 years isn't the same as saying that Earth's spin period will increase by 1 hour in that time. (I get the impression
      • Re:Hmmm... (Score:5, Informative)

        by multi io ( 640409 ) <olaf.klischat@googlemail.com> on Friday August 26, 2005 @02:08PM (#13410113)
        If you have to introduce 1 leap hour or 3600 leap seconds in 600 years, all that means is that the *average* length of the mean solar day during that time was 1hour/600years=~2e-7 longer than 86400 sec. How much of that elongation was actually caused by the earths's rotation slowing down, and how much was caused by, say, the fact that the rotation was a bit too slow from the start, is a different question.

        Now, AFAIK it happens to be the case that the definition of the second in the 1960s was indeed a bit too short with respect to the length of the mean solar day even back then, so the fact that the earth's rotation was too slow from the start will be the dominating contributor to the introduction of leap seconds for the next few centuries at least.

  • by MosesJones ( 55544 ) on Friday August 26, 2005 @06:59AM (#13406234) Homepage

    With this different rotation at the core, what type of Baseball pitch is the earth? And was it thrown left or right handed?

    Personally I think we've been thrown a curve-ball.

    Sorry couldn't resist.
  • by strannik ( 81830 ) on Friday August 26, 2005 @07:00AM (#13406239) Homepage
    We'll need to do core dump analysis.

  • by ReformedExCon ( 897248 ) <reformed.excon@gmail.com> on Friday August 26, 2005 @07:01AM (#13406240)
    If the core slows down due to friction with the mantle, will there be an effect on the magnetic field surrounding the Earth? Without the magnetic field, my understanding is that the Van Allen radiation belt will also not exist, and that in turn would expose the Earth to the full-on radiation of the Sun.

    I'm no scientist, of course. But I wonder what the implications of the spinning core means. Also, how long would it take to stop spinning, or to develop a wobble?

    There have been a slew of large earthquakes around the world lately. Could it be related?
  • Jeez no one subscribes to the Giant Hampster in a Giant Wheel at the core of the Earth theory anymore? I mean if that hampster dies then we are all really screwed.
  • While researching this, the scientists also discovered that the earth is not flat, and that gravity usually pulls towards the center.

    Seriously, though, what's the big deal? This wasn't even news 10 years ago, so why make a big fuss over it now...

    • I was wondering the same thing. I remember being taught this from about 7th grade through to Intro to Astronomy in college ( 2 years ago ). I think the only thing that shocked me about this article is the fact that it's been designated "news". I can understand a few months, maybe even a year or two, but this long?

      Whatever, though. At least it gave me to bitch about. I'm happy. :)
  • My spinning wheel is much faster and I don't do a announcement about it.
    • My spinning wheel is much faster and I don't do a announcement about it.

      Actually, there was a poll [slashdot.org] just a while back about it. You should have posted, really.

  • Anyone know if this might have any effect on the axial tilt and precession (41,000 and 26,000 year wobble cycles) of the Earth?
  • by Anonymous Coward on Friday August 26, 2005 @07:21AM (#13406352)
    God overclocked the core, and saw that it was good.
  • Aha... (Score:2, Redundant)

    Over a period of 700 to 1,200 years, the inner core appears to make one full extra spin.

    Couple that with the fact that a human's unprompted circadian cycle is actually about 25 hours long, and it begins to explain a lot... to someone...

  • Has a cure (Score:5, Funny)

    by La Gris ( 531858 ) <lea,gris&noiraude,net> on Friday August 26, 2005 @07:22AM (#13406359) Homepage
    Everyone head to the east with their car and go as fast as possible.

    And everyone around the world, press the breaks all at once, while riding to the east.

    That may be enough to accelerate the Earth's rotation :)
  • by Anonymous Coward on Friday August 26, 2005 @07:37AM (#13406414)
    How about New Scirntist's [newscientist.com] coverage? Or LiveScience.com [livescience.com]?

    No bugmenot required, and they're science sites.

    Slashdot gets more retarded every day, I swear.

    (this post's mind-reading captcha="resorts")
  • by aussie_a ( 778472 ) on Friday August 26, 2005 @07:39AM (#13406423) Journal
    I wonder what the rotation rate of Mars' core is. We know [planetary.org] it's either liquid or solid and liquid (the latter being what Earth has), so it could have a difference, which would create a magnetic field. Only problem is, Mars doesn't have a magnetic field. However, Mars' field might also be hiding, as it does on Earth when changing the north and south poles [wikipedia.org] which can take hundred to thousands of years. Now we've only been watching Mars with any sophistication for decades, which means Mars could have a field that's currently undergoing a reversal. If it isn't undergoing a reversal, and the two rotations are different, then it would prove enlightening on why that is the case.
  • This just in: the center of a 12" record travels at a greater number of RPMs than the outer edge. Reactions from the Doobie Brothers were not reported.
    • Re:Revolutions (Score:2, Insightful)

      by jsgates ( 232994 )
      Eh, wrong. They don't spin around at different RPM's, the outer edge spins faster than the center.
    • Re:Revolutions (Score:3, Informative)

      by beefstu01 ( 520880 )
      This just in: the center of a 12" record travels at a greater number of RPMs than the outer edge. Reactions from the Doobie Brothers were not reported

      Uh... no. The tangential velocity at the edge is much greater than the tangential velocity in the center. Both points have the exact same angular velocity, otherwise the record would break into many pieces. Silly boy, don't you remember Physics I?
    • slashdot poster jumps to moronic conclusion. Many in the community believe it may have something to do with smoking too many doobies whilst spinning platters.
    • Um, that's not possible?
  • It also bounces. (Score:5, Interesting)

    by kulakovich ( 580584 ) <slashdot AT bonfireproductions DOT com> on Friday August 26, 2005 @07:46AM (#13406467)

    The Earth's core also bounces from North to South. Not sure if it is a remnant of the colision that formed the Moon, or part of its conservation of momentum from the outer crust trying to change it's vector, the core being a giant defacto gyroscope.

    Eventually I will post the math. =)

    kulakovich
  • Cool, the nukes worked [imdb.com]. ;-)
  • 1996 (Score:5, Funny)

    by Black Parrot ( 19622 ) on Friday August 26, 2005 @08:04AM (#13406634)


    Great to see the timely Slashdot article. I need a reminder about these things every nine years or so.

  • by Himring ( 646324 ) on Friday August 26, 2005 @08:15AM (#13406721) Homepage Journal
    It's Superman's fault. All cuz that bitch, Lois Lane, went and died, so he flew real fast and sped up the crust, then switched it back, but now the inside is still all fucked up....
  • Stop (Score:3, Funny)

    by JustOK ( 667959 ) on Friday August 26, 2005 @08:45AM (#13406982) Journal
    Stop the world, I want to get off.
  • What if (Score:2, Funny)

    by diztort ( 910437 )
    ...there is no core what so ever? I mean, why didn't nobody think about that the crust we live on is just some excretion material of the exit from a blackhole? The other end of the tube so we live on the crap of some swallowed up planets and other materials. :)
  • Or should I say speculation, since I had no empirical data.

    Anyway, while at SCIENCE CAMP, I proposed to one of the adults a 'different core rotation rate theory.' I remember the look he gave me very clearly: "yeah, right."

    Of course, he was right to be skeptical. I was way off, apparently, since my proposal was that it was related to gravity, not the magnetic field. Oh, to be young again.
  • by ndansmith ( 582590 ) on Friday August 26, 2005 @11:18AM (#13408561)
    Fox News has posted a conflicting report declaring the Earth's core a "No Spin Zone."

"Everything should be made as simple as possible, but not simpler." -- Albert Einstein

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