What physical phenomenon governs the basic blue hue of the daytime sky?

Answer

Rayleigh scattering

The scattering of sunlight by the atmosphere's primary gas molecules, which preferentially scatters shorter wavelengths, is defined as Rayleigh scattering.

What physical phenomenon governs the basic blue hue of the daytime sky?

#Videos

Why does the sky look bluer in the fall? | NBC4 Washington - YouTube

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