Why is the sky blue?

This seems like a tricky question, but the answer is really simple! The light we have here on Earth comes from the Sun. Sunlight looks white, but is actually made up of all of the colors of the rainbow.

When sunlight moves through the air, the light gets scattered in all directions. It gets scattered forward, sideways, and backwards.

Air molecules scatter some colors of light better than others. Blue light is scattered the most. Since the blue rays of lights are scattered the most, they reach our eyes from all directions and we see more blue than any other color. This makes the sky look blue.

If you were living on Mars, and you asked your Martian parents about the sky there, you'd have to ask the question...why is the sky red? On Mars, dust in the air turns the sky red during the day and purple at night!

Submitted by Carlos (Texas, USA)
(July 28,1997)


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