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Counterbalancing the tilt of earth

  1. Aug 3, 2010 #1
    Hello,

    Recent NASA study has shown that the construction of Three Gorges Dam in China has contributed to shift in the pole thus increase in the tilt of the axis of rotation. Now my doubt is, can this tilt or shift in pole be restored by constructing another similar dam in diametrically opposite direction of Three Gorges?

    Some important things related to planet needs to be considered:

    1. All objects on the planet are subjected to Newtonian Gravity directed towards center of earth.

    2. Earth is rotating and not stationary

    3. Directions, North and South are meaningless in space

    I hope some expert would give the best answer for the counterbalancing of the tilt and shift in pole axis.

    Advance thanks,

    Harsha
     
  2. jcsd
  3. Aug 3, 2010 #2

    alxm

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    The NASA scientists Chao and Gross calculated that the filling of the Three Gorges Dam would affect the rotation, not the tilt, of the earth by 60 billionths of a second per rotation.

    They also calculated that the Sumatra earthquake sped up the planet by a few millionths of a second. That's a 1000x larger effect. And motions within the molten core of the planet can change the rotation by thousandths of a second.
     
  4. Aug 3, 2010 #3

    D H

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    Why?

    The change is incredibly small, too small to be measurable. It is a calculated result. The changes in the Earth's rotation rate and rotation axis due to large (very large) earthquakes are much bigger than those caused by the Three Gorges Dam -- and those earthquake-induced changes are also calculated rather than measured changes.
     
  5. Aug 3, 2010 #4
    Fine, in fact the same study has said that the Three Gorges Dam has caused a shift in pole by 0.8 inch.

    Even going by hypothetical case, that the Three Gorges Dam has tilted or shifted the pole, can it be counterbalanced by another dam in diametrically opposite location to Three Gorges Dam, please I need this answer precisely.

    Advance thanks

    Harsha
     
  6. Aug 3, 2010 #5

    Vanadium 50

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    Reference, please?
     
  7. Aug 4, 2010 #6
    North and South are not meaningless in space. Though linear constant velocity is relative, rotation is not. That is because a rotating object is continually undergoing acceleration.
     
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