Question

Why the sky is blue?

Answer 1

When the Sun is high in the sky, this is why the entire sky is blue. It appears a brighter blue the farther away from the Sun you look, because there's more atmosphere to see (and therefore more blue light) in those direction

Answer 2

Blue light is scattered in all directions by the tiny molecules of air in Earth's atmosphere. Blue is scattered more than other colors because it travels as shorter, smaller waves. This is why we see a blue sky most of the time. ... Also, the surface of Earth has reflected and scattered the light.
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