In what process sky colors (including blue sky and red sun) are created?
iridescence
Rayleigh scattering
mirage
atmospheric refraction
Rayleigh scattering, named after the British physicist Lord Rayleigh (John William Strutt), is an elastic scattering of light or other electromagnetic radiation by particles much smaller than the wavelength of the radiation. 
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iridescence
Rayleigh scattering
mirage
atmospheric refraction
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