The sky usually looks light b. If you go to the top of the highest mountain, there is less a between you and the sun to scatter (分散) the sunlight, the sky would be dark blue. If you take a space s high above the earth, there is no air at a to scatter the sunlight, the sky would be so dark that it would be black.

    Sometimes the sky doesn't l blue. A sunrise (日出) and sunset (日落), the light from the s is scattered in such a way that you see red, orange, and other colors in the s.