Iridescent Clouds Above Lethbridge, Alberta
January 15, 2013
Photographer: Patricia O. Polo
Summary Author: Patricia O. Polo; Jim Foster
The photo above showing an opalescent sky over Lethbridge, Alberta was snapped late in the day on November 11, 2012. The camera is facing toward the south. Iridescent clouds are often noted when mid-level wave clouds are visible as was the case this fall day. Composed of similarly sized water droplets, their metallic colors result from the diffraction of sunlight by the minute droplets. Though they can be quite vivid, iridescent clouds usually aren't nearly as bright as high altitude nacreous clouds, observed before sunrise or after sunset at polar latitudes. Always protect your eyes when looking near the Sun.
Photo details: Nikon D5100 camera; f/22; 1/ 800 sec. exposure; ISO 100; 200 mm.