One of our daily internet rituals (one that accompanies our regular checks of facebook, news sites, twitter, google reader… the list goes on) is a visit to NASA’s Astronomy Picture of the Day. One of the simplest websites we’ve ever come across, it presents a single new picture of the universe and brief explanation of the picture each day. It has no home page and does not have a particularly handsome design. Yet, unusually for the world wide web, it manages to create a moment of space and perspective each day. A chance to sit and wonder at, to learn about the world (and beyond) without leaving your desk. Today’s image, above, is described thus:
A Pileus Iridescent Cloud Over Ethiopia
Explanation: Yes, but how many dark clouds have a multicolored lining? Pictured, behind this darker cloud, is a pileus iridescent cloud, a group of water droplets that have a uniformly similar size and so together diffract different colors of sunlight by different amounts. The above image was taken just after the picturesque sight was noticed by chance by a photographer in Ethiopia. A more detailed picture of the same cloud shows not only many colors, but unusual dark and wavy bands whose origins are thought related to wave disturbances in the cloud.