Why do sunrises and sunsets often display deep orange and red hues, especially when the Sun's path is shallow?

Answer

Almost all the blue light has been scattered out of the line of sight.

When light enters the atmosphere at a shallow angle near the horizon, the cumulative effect of scattering over the extremely long path length removes almost all the blue light, leaving behind the longer, visible red and orange hues.

Why do sunrises and sunsets often display deep orange and red hues, especially when the Sun's path is shallow?

#Videos

And Why The Stars Change With The Seasons" 5 min. version

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