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Sun light

  1. Sep 13, 2005 #1
    This is a thing that I would like help with.

    If I was sitting on the sun (impossible I know) would I see light from any other source entering my location? If not why not?
  2. jcsd
  3. Sep 13, 2005 #2
    I believe no, but only because your pupils would be too dialated to see the stars (like if you try to look at the stars while someone's shining a flashlight in your eyes).

    Do you have reason to think otherwise, jjw004?
  4. Sep 13, 2005 #3
    Hi Severian 596:

    You are no doubt correct but I was not focused on Human frailities.

    This was intended as an exercise in whether light intercepts other light sources.
    Way over my head but something I would like opinions on.

    If all else fails I may be compeled to venture some thing as you request.

    Jim Wood
  5. Sep 14, 2005 #4
    I always thought that ones eyes dilates in the darkness and when you pass a flashlight through the eyes they shrink. (Dilates to allow more light to enter.)
  6. Sep 14, 2005 #5
    You know, you're right! You learn something new every day. =D
    Dilated: made wider or larger in all dimensions; "a dilated pupil"

    Jim, light behaves like a wave, so it sounds like you're interested in wave interference behavior. Here you go!

  7. Sep 14, 2005 #6

    Claude Bile

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    Jim, even if you used a perfect light detector, the optical noise from the sun's emissions would swamp just about any external light source with the exception of perhaps a nearby quasar or supernova.

    In short, it would take an extremely powerful light source to overcome the optical noise generated by the sun.

  8. Sep 15, 2005 #7


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    Well, the sun doesn't have a surface, per se, so "sitting on the sun" is somewhat ambiguous. The disk of the sun that we see when we look up into the sky is called the photosphere. This can be crudely thought of as the deepest part of the sun from which a photon can escape without scattering away. If we can see down to the photosphere, then one might naively think that we could see out from it. This is not the case, however.

    Why? Think about the pictures you've seen of, for example, Mars. With a decent telescope, you can see the surface very clearly. However, if you look from its surface, as the rover did:

    Surface of Mars

    then you won't see the earth or any stars. The basic reason is that, although most of the light can make it through the atmosphere, the small fraction of it that doesn't is enough to fill the sky with a haze of scattered light. The same would be true on the photosphere of the sun. In principle, a very precise instrument might be able to separate the stars from the scattered background light, but our eyes wouldn't even come close. That's why Severian596 was emphasizing the limitations of the human eye.
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