PINK FACTOR X7

As a ray of white sunlight travels through the atmosphere, some of the colors are scattered out of the beam by air molecules and airborne particles. This is called Rayleigh scattering. Colors with a shorter wavelength, such as blue and green, scatter more strongly, and are removed from the light that finally reaches the eye. At sunrise and sunset, when the path of the sunlight through the atmosphere to the eye is longest, the blue and green components are removed almost completely, leaving the longer wavelength orange, red and pink light. The remaining pinkish sunlight can also be scattered by cloud droplets and other relatively large particles, which give the sky above the horizon a pink or reddish glow.