Question: why is the sky blue?

Hugh Manning answered on 8 Nov 2018: last edited 8 Nov 2018 5:48 pm

The light we get from the sun looks white to us, but is actually made of a lot of different colours, this is called the spectrum of visible light you can see all these colours in a rainbow, or when you separate light using a prism!

All light travels in a straight line unless something gets in the way and does one of these things reflect it (like a mirror) bend it (like a prism or water) block it (with something that’s not transparent) or scatter it (like gases in the atmosphere).

The gasses in the sky (mostly nitrogen and oxygen) scatter the blue light much more than they do red light. So during the day we see this as a blue sky, in the evening time the suns light relative to use has all be scattered of the blue light and so it looks red!
Hopefully this image helps explain it!