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Thread: What color is the sun?

  1. #21
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    I have a thought... Does the atmosphere by any chance filter green/blue wavelengths?

  2. #22
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    the color of the sun? Does that refer to the color of the light it emits? Or the surface of the sun itself? I suppose there is a difference..

  3. #23
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    How can there be? The colour it emits will be the same colour we see it as.

  4. #24
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    there could be huge differences. The gases surrounding the sun could be blocking lots of other wavelengths that we wouldn't be able to observe from here. Why then is the sky blue? Space isn't very blue.. Come to think of it, does the sun even have a defined surface level? Would it be liquid? Gaseous?

  5. #25
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    Let's conclude that the sun is ........RGB!

  6. #26
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    Quote Originally Posted by madgadget View Post
    You can get plenty of green fireworks. That's black body radiation.
    So you're telling me all of these fires have drastically different temperatures?


  7. #27
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    .......it's grey now.

  8. #28
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    I think the color of the clouds is probably the easiest way to see the color of the sun. Clouds reflect all visible wavelengths equally well, so they have the same color as sunlight. I haven't seen a lot of yellow clouds recently, but maybe we just don't get those in Sweden?

    Another thought regarding the sun's color... Isn't it reasonable to think that we as a species have adopted its color as white?

    Quote Originally Posted by madgadget View Post
    You can get plenty of green fireworks. That's black body radiation.
    Actually black body radiation never appears green. The green emission from fireworks is typically from excited barium species (BaOH or BaCl depending on composition).
    Quote Originally Posted by madgadget View Post
    I have a thought... Does the atmosphere by any chance filter green/blue wavelengths?
    The atmosphere filters mainly UV and IR, but due to Rayleigh scattering more blue light than red is scattered (which is why the sky is blue). Effectively the sun is a bit more blue above the atmosphere.
    Quote Originally Posted by carlos3621 View Post
    Let's conclude that the sun is ........RGB!
    Well, no... the sun emitts much more than just the three primary colors, so I wouldn't call it RGB.

  9. #29
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    Quote Originally Posted by tocket View Post
    I think the color of the clouds is probably the easiest way to see the color of the sun. Clouds reflect all visible wavelengths equally well, so they have the same color as sunlight. I haven't seen a lot of yellow clouds recently, but maybe we just don't get those in Sweden?

    Another thought regarding the sun's color... Isn't it reasonable to think that we as a species have adopted its color as white?
    The colour of the light from the sun at the Earth's surface corresponds very closely to the D65 standard illiuminant, which is one of the many "white" colours that exist. It's very slightly yellowish. While the sun's photosphere is at about 5700 K, there is a contribution of light from the corona (which is very much hotter, and therefore bluer) and there are filtering effects in the atmosphere, mostly revolving around the dust particles present there, which end up with a colour temperature of about 6500 K.

  10. #30
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    There certainly are a lot of whites, but calling D65 a yellowish white I don't understand. I think it's more to the blue than to the yellow. Looking at the CIE1931 coordinates it is definitely to the blue.

    Do dust particles really contribute significantly to changing the spectral distribution?

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