photograph by en.wikipedia.org

Ok so if the sky is blue, why are sunsets red? As we explained earlier, as light travels through the atmosphere it is scattered, and because of a phenomenon called Raleigh Scattering blue light is the most likely to be scattered while red light, on the other end of the visible light spectrum, is the least likely to be scattered. Well as the sun sets light from the sun hits the earth at a different angle and has to travel through more of the atmosphere.

This makes the light more likely to run into stuff and scatter. As the sun sets blue light is scattered so much that it never even reach our eyes, and as the sun set progresses, first green, then yellow, and then orange light begins to scatter throughout our atmosphere, creating all of the different hues of a sunset. Finally, just before the sunsets, light is traveling through so much atmosphere that only the red photons are able to make it to earth, making the sun and sky appear red.