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in reply to Re^3: How many colors does a rainbow have?
in thread How many colors does a rainbow have?

But there are also colors in the infrared and ultraviolet present as well.

Isn't this a contradiction? Colo[u]r being those frequencies of light visible to humans... and infra-red and ultra-violet not being among those...?

While each atom in the photosphere may emit light at one quantum frequency, the sun is so hot that doppler shifting of the light causes the lines to "fuzz out" so that you see essentially a continuous spectrum of light.

I might be wrong about this, but isn't the vast majority of the sun's radiation thermal, i.e. blackbody, i.e. continuous in the frequency domain? Yes, there are spectral lines caused by atomic de-excitation, and they are broadened by Doppler shifting due to the temperature of the gas in the sun (amongst other things) but this isn't what the majority of radiation emitted from the sun is.. is it?

Someone help me out here!
why_bird
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