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Colour of the sky from space

  1. Feb 3, 2016 #1
    suppose there is an astronaut sitting in a space station orbiting Earth, what colour would the sky appear to him?
    Same as us? Why or why not?
  2. jcsd
  3. Feb 3, 2016 #2

    Simon Bridge

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    Did you try finding a photo taken from "space" (there are many online) and looking for yourself?

    Also: it would help to be more precise in your terms. What is "sky"? It's usually defined as the apparent dome you see when you are on or close to the ground, so what would "sky" mean when you are not close to the ground?
    i.e. aircraft are often said to be "in the sky" ... so is the sky downwards and to the sides as well as up?
    Spacecraft are above the sky - so is the sky down towards the Earth? If the spacecraft were exactly half way between earth and Mars ... where is the sky?
  4. Feb 3, 2016 #3
    Yes I've looked for myself
    Rayleigh scattering..is that all to it? Even when one sees it from 'space'.
  5. Feb 3, 2016 #4


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    1. Google will provide you with pictures.
    2. How is it that you can even see the sky at all -- and why would that reason be different in space?
  6. Feb 3, 2016 #5


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    The 'colour' of the sky irom Earth is very pale (desaturated). Looking down through it to the more saturated colours on the ground and all you might expect is that it would give everything a very slighy blue cast. There would be a reddish ring around parts of the outside (corresponding to a sunset sky), I suspect but, again very diluted by the reflected Earth light or direct sunlight.
  7. Feb 3, 2016 #6
    And since air is only blue when Rayleigh scattering makes it so, you'll only see this blue cast when you're correctly lined up with the sun.
  8. Feb 3, 2016 #7


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    You can Google for pictures of Earth from orbit. The main difference/issue is that when you look up, the sky is against the blank/black canvas of space, but when you look down, the earth itself is the backdrop. So you need to look at pictures focusing on the horizon, where the earth doesn't provide most of the color.

    And there is also a contrast issue when looking down: the earth is brighter than the shy, making it hard to see the sky.
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