Why does the sky appear blue during the day on Earth?

Answer

Because gas molecules scatter shorter wavelengths of light, predominantly blue and violet

On Earth, sunlight hits gas molecules like nitrogen and oxygen, which are highly effective at scattering shorter wavelengths, especially blue and violet light, in every direction. This scattering process, known as Rayleigh scattering, bathes the environment in diffuse blue light.

Why does the sky appear blue during the day on Earth?
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