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    Re: Japan earthquake speeds earth's rotation
    From: Bill B
    Date: 2011 Mar 15, 04:07 -0400

    On 3/14/11 1:38 PM, Lu Abel wrote:
    > The scenario is similar to that of a figure skater drawing her arms
    > inward during a spin to turn faster on the ice. The closer the mass
    > shift during an earthquake is to the equator, the more it will speed up
    > the spinning Earth.
    
    This analogy confuses me.
    
    If a figure skater draws his/her arms in (nearer to the axis of
    rotation), the rate of spin increases. OK.
    
    "The closer the mass shift during an earthquake is to the equator, the
    more it will speed up the spinning Earth." I am not clear, assuming the
    temblor does not solely move the island (in this case) closer to the
    axis of rotation) what affect a shift would have based on its
    relationship to the equator.
    
     From a layman's vantage point, a 100 mile move from a pole towards the
    equator would be greater shift relative to the axis than a move from 100
    miles north or south of the equator to the equator.
    
    Finally, the post stated,"More impressive is that the entire main island
    of Japan (Honshu) moved eight feet to the east!"
    
    East is neither towards or away from the equator. So why the speed
    change in simple terms?  Action and reaction?
    
    Bill B.
    
    
    
    
    
    
    
    

       
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