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Combined velcoities of earth's rotation and revolution + sun + galaxy

  1. Feb 14, 2007 #1


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    since the earth turns around itself , turns around sun, sun turns around galaxy, galaxy is in movement (or maybe orbiting something bigger, who really knows ?)

    Well with all these movements, our velocity must be close to c ?

    thus , what is galaxy turns around ...., which turns around...., which turns around ...., ect

    how can we really localise ourselves with dots that dont move (to measure true position + velocity), apart from just using starts really really far away ?
  2. jcsd
  3. Feb 14, 2007 #2


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    Science Advisor

    There is no true position, neither is there true velocity.
    There is only relative position and relative velocity.
    That insight ist at the heart of modern physics.
  4. Feb 14, 2007 #3


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    Staff: Mentor

    This exact question is open near the top of this forum....

    The answer, in addition to what was already said, is no, adding up all those velocities doesn't get you anywhere close to C, so it isn't even relevant to think about time dilation due to speed between most objects in the galaxy.
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