Why is the sky blue and the grass is green?
First; why the sky is blue. The answer “The sky is not blue” is not necessarily wrong. The sky APPEARS to be blue; for the following reason: I think most people know that sunlight is made up of light of several different wavelengths, and can be split up into the colours of the rainbow. Blue light has the shorter wavelength, and red the longest wavelength. When sunlight hits the molecules in the atmosphere, the light is absorbed; causing the molecules vibrate and and give off, or ‘re-emit’ the light. This is called ‘Rayleigh Scattering’. Because the molecules vibrate in all directions, the light is emitted in all directions (called ‘scattering’). Because the blue wavelength is shorter and more energetic than the red or yellow, it reacts much more with the air molecules, which tend to pass straight through. Because the blue radiation is re-emitted from the air molecules in all directions, it seems to us looking from the ground that the blue light is coming from everywhere; hence the sky
