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Earth's Core Spins Faster than Earth

Posted by CowboyNeal on from the round-and-round dept.

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.'"

3 of 309 comments (clear)

  1. New York Times? Why?????????? by Anonymous Coward · · Score: 4, Informative

    How about New Scirntist's coverage? Or 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")

  2. Re:Are we due for a reversal of the poles? by dwhipp3980 · · Score: 3, Informative

    What you heard on Discovery is correct. It has been postulated that the flow of the fluid outer core, and subsequent motion of ions within that fluid is responsible for the generation of Earth's magnetic field and geomagnetic poles. It has also been shown that the polarity of the dominantly dipolar magnetic field reverses, seemingly randomly through Earth's history. I'm not sure of the statistics you mention, but if in fact the average pole reversal period is shorter than the time during which the current polarity has been maintained, you should also consider the standard deviation of the reversals, which is huge. For example, during the Cretaceous geologic time period, there was a long period of normal (or similar to today) polarity known as the Cretaceous long normal. Geologic records show no reversals over this 43 million year time period.

  3. Re:Hmmm... by multi+io · · Score: 4, Informative
    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.