We've all asked the question 'why is the sky blue?', except for me. I'm here to answer it.
To discover why the sky is blue, you need to first know that the Earth's atmosphere the mixture of gases and other material like water vapor, ice crystals, dust, ashes, pollen, and even salt from our oceans. But none of those things are blue, so what's the deal?
Well, that's where light comes in. Light is energy that travels through space in a straight line until something disturbs it. Light contains all the colors of the rainbow which are measured in different wavelengths of energy.
When light hits a gas molecule, some of it may get absorbed. After awhile, the molecule radiates the light in a different direction. The color that is radiated is the same color that was absorbed. All of the colors can be absorbed, but the higher frequencies (the blues) are absorbed more often than the lower frequencies (the reds). This process is called Rayleigh Scattering. The absorbed blue light is then radiated in different directions and gets scattered all around the sky. So whichever direction you look, the sky above looks blue.