Unit 9, The Blue Sky Joe asked me something about science just now, but I didn't know the answer. I'm good at science. Ask me. Okay. Why is the sky blue? I'll explain it in a simple way. Light comes through the air from the sun in waves. The light is in many colors, right? Right. Blue light waves are smaller than air molecules. They sometimes get absorbed by these molecules. Okay. What happens then? Then the blue light waves scatter in many directions. Your eyes see this blue light from above you after it leaves the air molecules. So that is what makes the sky blue. What happens to the other colors? They reflect off the things that they hit. Your shirt is red because our eyes see the red light reflected from it. Now I understand why the sky is blue.