As parents, this is a question we all have been asked and had no answer to give.  Since kids think we know everything and we want them to believe we do for as long as possible you will now have the answer.

The sky is blue due to Rayleigh scattering.  There you have it.  

Now you can leave it at that or wait for the quizzical look to disappear and be asked the next question which is “huh”?

Well (insert child’s name) Rayleigh scattering is light waves passing through the atmosphere.

Here is where it gets scientific.  Very little amounts of the red, orange and yellow light is affected by the air, but the shorter wave length light is absorbed by the gas molecules.  (You are sounding like a real expert now! Don’t stop!)

This absorbed blue light is radiated in different directions.  It gets scattered – no matter where you look (insert child’s name) this blue light reaches you.  You see it everywhere you look so that is why the sky is blue.

You just impressed the heck out of your kids – and now they can go explain it to their classroom where the teacher might not even know the answer unless they read this blog.

See ya!