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Crossing speed of light

  1. Jun 22, 2015 #1
    one thing every one says that our (any) galaxy is hundreds and thousands of lightyear long and also they rotate about their center then if they rotate with very low angular velocity then also the velocity of the extreme will cross the light speed?
    will it just think nd reply...

    (v=ω X r)
  2. jcsd
  3. Jun 22, 2015 #2


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    No, the angular velocities in galaxies are not large enough to go faster thn the speed of light. The velocity of the Sun relative to the galactic center is about 220 km/s. Large, but far from the speed of light, ca 300000 km/s.
  4. Jun 22, 2015 #3


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    In addition, galaxies don't rotate like they were a single rigid object. Once you get away from the central bulge the velocity curve goes pretty much flat. (the orbital velocities of the stars stay pretty much the same no matter how far our or close in they are.)
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