Why Isn't The Sky Purple?
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If you know the explanation for why the sky's blue, you've heard that sunlight is whitelight composed of many frequencies and that higher frequency, bluer, light scatters inthe air more than lower frequency, redder, light. So, you might ask "why isn't the skyviolet, since violet is an even higher frequency than blue?". First off, ultraviolet lightand x-rays are also higher frequency than blue, and that doesn't mean the sky is thecolor of x-rays… Both because we can't see them and also because the sun doesn't makevery many of them and then the atmosphere blocks them all - which is probably why wedidn't evolve to be able to see them. And secondly, the color violet in the rainbowis the "roses...
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If you know the explanation for why the sky's blue, you've heard that sunlight is whitelight composed of many frequencies and that higher frequency, bluer, light scatters inthe air more than lower frequency, redder, light. So, you might ask "why isn't the skyviolet, since violet is an even higher frequency than blue?". First off, ultraviolet lightand x-rays are also higher frequency than blue, and that doesn't mean the sky is thecolor of x-rays… Both because we can't see them and also because the sun doesn't makevery many of them and then the atmosphere blocks them all - which is probably why wedidn't evolve to be able to see them. And secondly, the color violet in the rainbowis the "roses...
