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Homework Help: If I could travel close to the speed of light

  1. Nov 28, 2008 #1
    Say I was embarking on a journey to Neptune at 95% the speed of light.

    Neptune has a minimum distance of 4.3 billion km from Earth. If I was travelling at 2.85 x 108 m/s, I would take 4 hours 11 minutes and 38 seconds to get there. Is this even possible?

    1)What would I see of my surroundings, would I be able to see anything at all?

    Would I be able to see anything at all, since I'm travelling close to the speed of light?

    2)Would I have any communications difficulties?

    Since I'm travelling at such an insane speed, I would encounter time dilation, which would make communications with Earth difficult because we are in different time references, right? And will the Doppler effect affect me as well?

    3)What relativistic effects (time dilation, aging - twin paradox, etc.) will I face?

    Could someone elaborate on this because I really can't grasp this concept of time dilation and the twin paradox thing.

    4) What happens on my return journey?
  2. jcsd
  3. Dec 2, 2008 #2
    Leaving aside the incredible amount of energy required to accelerate you to such a speed and the decelerate once you got to Neptune (great destination) the 4hr11min38sec journey time is measured by whom? You are in the time dilation zone so for you the measured journey time will be a bit less.
    On the Web you should be able to find visual examples of the distortions you would see travelling at such a speed.
    If you were shining a light out of the rear porthole of your spaceship would it look bluer or redder than usual to someone observing it from Earth?
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