Tuesday, February 6, 2007
A zoomed-in image of the mirage seen on the Alappuzha-Chenganassery State Highway. Mirage is an optical illusion, wherein one sees a non-existent pool of water over heated surfaces like roads, pavements, deserts etc. The air immediately above the road is much hotter, forcing the light rays to bend, a phenomenon called refraction. The pool of water is actually a distorted image of the blue sky. The light rays from the sky falling on the hot surface get distorted because of extreme heat and appear from a distance as a pool of water. Objects like vehicles are seen in this pool. Since the vehicles are seen below the normal surface, such mirages are called inferior mirage. What is pictured above is also called "highway mirage". The opposite is superior mirage, which is typically seen in very cold conditions. Objects are seen floating in such situations.