Full Moon and Backlit Clouds
January 12, 2004
This photo was taken on December 9, 2003 from Corralitos, California and shows a storm cloud backlit by the Full Moon. It was snapped in the early morning, a little before sunrise, facing north-west. The main cloud formation to the right side of the image is a cumulonimbus cell. It's likely that the edge of this cloud (the portion in front of the Moon) is composed of uniform water droplets. Notice the faint corona about the Moon (pastel colors), which result from diffraction of light. With diffraction, water droplets in clouds, or in some cases ice crystals, interfere with light rays (moonlight), producing rather inconspicuously-colored interference rings.