Can a lake vanish? A few minutes ago you saw cool water shimmering just up the road. But now all you see is hot, paved highway. Where is the lake?
The disappearing lake is a mirage – something that isn’t what it seems to be. The mirage is made by light reflected from something far away. You may see a mirage when layers of cool air and warm air are close to the earth.
Light usually travels in a straight line. But when light passes through layers of warm air and cool air, it acts differently. The warm layers and cool layers act like a lens. A lens is a curved piece of glass or plastic that bends light to make things look bigger or smaller. The warm and cool layers bend the light.
If the bottom layer of air is warm, the mirage will be close to the ground. But if the bottom layer is cold, the light will bend the other way. The mirage will be high up – it may even seem to float in the air!
A mirage can come from surprising places. A “lake” may be light waves from far-off clouds. A rocky “island” may be light waves from a distant mountaintop. People at sea have seen “ghost ships” floating upside down in the sky – images of real ships far away on another part of the ocean. And people sailing on the Strait of Messina off the coast of Italy sometimes see an “enchanted city” floating in the water!
Picture Credit : Google