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		Photos ©Les Cowley       Sunset mirages, two or more images of the sun, are seen when its low slanting rays are unusually refracted between air layers of different temperature. Usually the air temperature falls smoothly with increasing height. The most we then see is a slightly flattened sun. A mirage needs more severe temperature variations. One class of mirages, M-Mir sunsets, occur when there is a temperature inversion – warm air overlays cooler layers. The sunset at left was produced by a temperature inversion. The cooler air trapped below the inversion is visible as the darker layer. Sometimes there are several inversion layers and we see the sun miraged into multiple pancake-like shapes. Another sunset mirage form, Jules Verne called it an “Etruscan vase”, occurs when the sun-warmed afternoon sea produces an abnormally hot air layer immediately above its surface. Miraged suns often presage the elusive green flash!