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Can you see the surface of the Earth from the past

  1. Aug 9, 2014 #1
    If you can "catch up" to the light reflected from the Earth at that time in the past. What kind of resolution would you get? Could you zoom into the surface such that people/animals could be visible.
     
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  3. Aug 9, 2014 #2

    Chronos

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    A more practical approach would be to observe the reflection of earth from some distant object, given that nothing can overtake a photon. What kind of distant body would be sufficiently reflective, and where to look for one, is an issue.
     
  4. Aug 9, 2014 #3

    Matterwave

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    Sadly, you can't "catch up" to the light that was emitted by the Earth since light is the fastest thing in the universe.

    But if you're asking what an alien in another star system might see, then it really depends on what he is using to look at the Earth. The bigger the telescope, the better resolution he will have.
     
  5. Aug 9, 2014 #4

    billy_joule

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    The resolution is the same.

    Imagine looking at the earth from Alpha Centauri right now, you'll see the earth as it was 4.4 years ago.

    The view will be the same weather you traveled via a hot air balloon or via instantaneous teleportation.
     
  6. Aug 13, 2014 #5
    I would say that at astronomical distances, the light reflected by the Earth (which is not that much to start with) gets so spread into space that looking from any single definite location it would be practically impossible to see anything of the size of a person or an animal, no matter how big your telescope was. The amount of photons you could collect would simply be too small.
     
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