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Stars from outside the atmosphere

  1. Jul 12, 2010 #1
    Hi Guys ..
    I have a question and I hope I get a good and obvious answer PLZ ..
    How do stars and moon look like from outside the Earth's atmosphere ?
    If we went out of the atmosphere of the Earth , will we see the stars in the same way as we see them from .. here ?
    In other words do the atmosphere affect the light coming from stars and the moon ?
    Thanks ..
  2. jcsd
  3. Jul 12, 2010 #2


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    See Hubble photos, it is an orbital observatory. Earth's atmosphere causes stars to twinkle. This effect also makes it difficult to achieve high resolution photographs. The Hubble does not suffer these effects.
  4. Jul 12, 2010 #3
    Hi chronus , thanks for reply .
    I really saw the Hubble photos , but all photos I got are processed , so that they are not exactly what we can see by our eyes !
    I also heard about twinkling "Scintillation" but I'm wondering ' is it the only phenomenon that is because of the atmosphere ' ??
    Thanks !
  5. Jul 12, 2010 #4
    The atmosphere is always in between the light that enters our eyes from outside of space! Which is why almost any light that passes though the atmosphere has the chance of being affected. All the dust/pollution also play an affect in scattering the light. The turbulence of the atmosphere refracts the light from stars in different directions - hence the twinkling. Rayleigh scattering explains the colors produced in the sky from a sunrise or sun set. There are more phenomena as you put it - from a "red moon" (increased dust or pollution in the sky can make the moon look larger and have an orange or red tinge to it) to even the color of the blue sky itself. There are numerous resources on the web that explain all these different effects our atmosphere has on the light that enters it.
  6. Jul 12, 2010 #5


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    Except for the relatively minor issue of twinkling, they wouldn't look much different. Though without light pollution, you'd see more of them.
  7. Jul 13, 2010 #6


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    Even earthbound astrophotographers rely on image processing. The hubble has the advantage of not having to compensate for atmospheric effects. It is a fantastic instrument and well worth the expense.
  8. Jul 13, 2010 #7
    so I guess from your replies that the sky also looks beautiful in the outer space :)
    Thank you all ..
  9. Jul 16, 2010 #8


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    One other thing (besides the lack of twinkling, lack of haze, lack of light pollution, etc). The stars would have a somewhat bluish tint to them compared to how we're used to seeing them on Earth (Heisenberg might might have alluded to this in post# 4, but didn't directly state it).

    The Sun, instead of having a yellow color, would instead appear significantly closer to white. Other stars would follow suit, appearing a little more bluish.

    This difference is because the atmosphere scatters blue light much more than other colors -- it is the very reason the daytime sky is blue. But don't forget it is the (mostly) same reason why the sun is yellow. The major reason that we perceive the sun as yellow instead of white is because much of the blue part of the spectral energy is scattered in other directions, leaving a yellowish light we see from its location.

    The same basic idea applies to stars. Stars that appear white on Earth would appear a little bit bluish in space; and yellow stars would appear more white. :cool:
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