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What Causes the ‘Blue’ in the Sky During the Day?

The sky is blue because the sunlight bounces off the tiny particles in the air. When light enters the atmosphere, it hits molecules and small particles that scatter the light in all directions. Blue light scatters more than other colors, so we see a lot of blue from above us. It’s like when you shine a flashlight through a glass of water, the light spreads out, and sometimes it looks bluer.

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Examples

  1. When you're outside on a bright day, the sky looks blue because tiny air molecules scatter the blue light from the sun all around.
  2. If you look at a glass of water with a flashlight, the light spreads out and sometimes appears bluish, similar to how the sky works.
  3. The blue color in your favorite sky is like a giant, invisible filter that makes blue light bounce everywhere.

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Categories: Science · light,scattering,optics