The color of light from the sky is a result of Rayleigh scattering of sunlight, which results in a perceived blue color. On a sunny day, Rayleigh scattering gives the sky a blue gradient, darkest around the zenith and brightest near the horizon. Light rays coming from the zenith take the shortest-possible path (1 ⁄ 38) through the air mass, yielding less scattering. Light rays coming from the horizon take the longest-possible path through the air, yielding more scattering.