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B Water colour in Mars

  1. Jul 28, 2018 #1

    Delta²

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    I guess water in earth , in big lakes or seas, looks blue because the earth's sky is blue and the water's surface reflects the sky.

    Now if there would be some big lake of water at Mars, how the water surface colour would be? I guess the colour of Mar's sky which is red (right or wrong?)

    It is just that the greek version of msn.com posted some news with a lake been discovered in Mars (beneath some sort of ice) and it shows the lake's colour (or the ice's colour) in blue, I guess that colour in the photo is added in post production.

    Here is the news link, the text is greek but I suppose you all can see the photo
    https://www.msn.com/el-gr/news/tech...καλύφθηκε-στον-άρη/ar-BBLby57?ocid=spartandhp
     
  2. jcsd
  3. Jul 29, 2018 #2
    Your assumption is not correct. The light falling on the water surface consist of all wavelengths, i.e. it is "white light". The reason why deep water in oceans appear blue is because majority of longer wavelengths are absorbed, and mostly blue is scattered and reflected.
     
  4. Jul 29, 2018 #3

    Delta²

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    Well your argument seems sort of correct but when you saying that my assumption is not correct, you mean that the colour of the sky has minimal effect on the colour of the water ?

    And what is the colour of Martian Sky by the way ?
     
  5. Jul 29, 2018 #4
    Yes, that's what it means. The color of water mainly results from direct sunlight (which isn't blue) passing the water before and after it is scattered or reflected to the observer.

    https://en.wikipedia.org/wiki/Extraterrestrial_skies#The_color_of_the_Martian_sky
     
  6. Jul 29, 2018 #5

    Chronos

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    The martian atmosphere appears reddish because it contains a large amount of dust. A popular explanation is this dust has a high iron oxide [rust] concentr, but, this only partially accounts for the reddish hue. It has as much to do with particle size, which selectively affects the color of light that makes it through the atmosphere., and also accounts for how it appears at frequencies other than the visible spectrum.
     
  7. Aug 4, 2018 #6

    LURCH

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    Given this filtering effect, can we conclude that water on Mars would in fact have a reddish tint, given that most of the light reaching the water is red?
     
  8. Aug 10, 2018 at 4:22 PM #7
    What about the lake on Mars, that nobody cared about in this thread, this is huge discovery!!
    Is it true or fake news?!
    Do you have english version?
     
  9. Aug 10, 2018 at 4:29 PM #8

    phinds

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    It's a mile underground so isn't going to reflect anything.
     
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