Why are Skies blue and Clouds white?
To understand why the sky is blue and clouds are white, you have to realize that the white light from the sun consists of all the colours of the rainbow. Light travels as waves of different lengths; each colour has its unique wavelength. In addition, light will travel in a straight line unless something sends it off in a different direction. As it turns out, air molecules are just the right size to send the shorter wavelengths of light, mostly blue, off in different directions. Longer waves, such as red, are not scattered by air molecules. As sunlight enters the atmosphere the blue light is scattered by air molecules. The blue light waves spread all over the sky and down in all directions. No matter which way you look, blue light, which is better described as scatted blue light waves, is coming at you from that direction. That explains why the colour of the sky is usually blue. The sky may also turn white or gray on hazy days while hazy air has plenty of moisture and condensation nucle
