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Earth's axis

  1. Jan 25, 2005 #1
    hey there, idunno if this has been discussed before.

    there were a lot of articles abt a minor change in the tilt of the earths axis
    becoz of the tsunami , does tht mean our pole star have also changed ?

    any other noticeable effects of this ??

    than x

  2. jcsd
  3. Jan 25, 2005 #2


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    Hi vinee welcome to these Forums!

    The change to the Earth's axis is very small and has not affected Polaris, the Pole star, being near the celestial pole. It is about 10 away from it in any case.

    However there is a precession of the Earth's axis, because it is wobbling like a spinning top, which means the Earth's celestial pole describes a circle on the celestial sphere that is 570 in diameter. However it takes about 26,000 years for the Earth to complete one ‘wobble’ and it is only noticed if you observe the position of the stars relative to the rotation of the Earth very carefully over a period of time. Eventually the North Celestial Pole will move away from Polaris and other star will have the distinction of being ‘the Pole Star’.

    Nevertheless the ancient Greeks knew about this precession, which means they must have kept accurate records over a long time!

    A spinning top wobbles because of the action of the Earth’s gravity; the Earth itself wobbles because of the action of the Moon’s gravity on it.

    I hope this helps.

  4. Jan 25, 2005 #3
    thanx a lot
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