Daily Archives: August 27, 2012

On a day with high ice clouds, you are likely to see shiny, colored regions at either side of the sun. These are sundogs, an optical effect caused by refraction and dispersion of the Sun’s light through ice crystals. When the light rays strike the boundary between the air and water, like an ice crystal, several things can happen. Some rays are turned back in the direction from which they came, the familiar process of reflection. Other rays are transmitted into the crystal. Some of the transmitted rays change direction, a process known as refraction. Continue reading →