Why Is the Sky Blue During the Day and Black at Night?

The sky changes color because of the way light moves through air. During the day, sunlight comes all the way down to Earth and bounces off tiny particles in the air, which makes the sky look blue. At night, there's no sunlight, so the sky looks black. It’s like when you turn on a flashlight, the room is bright near the light, but it gets darker as you move away from it.

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Examples

A blue sky is like when you're standing close to a bright lamp, light spreads out and makes everything look blue.
At night, it's like being in a room with no lights on, the sky becomes black.
If you go up high in the air or into space, the sky gets darker because there are fewer particles to scatter the light.

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Categories: Space · light· space science· atmosphere· astronomy· sky colors