What causes a mirage?
A mirage is a naturally occurring optical phenomenon in which light rays are bent to produce a displaced image of distant objects or the sky. The word comes to English via the French mirage, from the Latin mirare, meaning “to look at, to wonder at”. This is the same root as for “mirror” and “to admire”. Like a mirror, a mirage shows images of things which are elsewhere. The principal physical cause of a mirage, however, is refraction rather than reflection. In contrast to a hallucination, a mirage is a real optical phenomenon which can be captured on camera, since light rays actually are refracted to form the false image at the observer’s location. What the image appears to represent, however, is determined by the interpretive faculties of the human mind. For example, inferior images on land are very easily mistaken for the reflections from a small body of water. Mirages can be categorized as “inferior” (meaning lower), “superior” (meaning higher) and “Fata Morgana”, a kind of superior
This is an article from lightscience.com about what causes a mirage; Mirages by Jeanette Cain What is a mirage? A mirage is a misleading appearance. Most mirages occur on the seas or in the deserts. What will cause a mirage? A reflection. What causes reflection? Light. We seldom consider light as anything magical or wonderful, but light allows us the ability to see many good things and, often, many bad things. Mirages, also called illusions, are caused by a reflection of some distance object which allows you to think that it is close by. In physics, it is known as an optical illusion. The more common type of mirage is called inferior mirage. It happens when a refraction of light passes through the atmosphere layers with varying qualities. Distance objects may seem to be raised above or below their normal locality. These objects may be seen as irregular and fantastic shapes. In warmer climates, such as deserts and sandy plains, mirage
A mirage is a naturally-occurring optical phenomenon, in which light rays are bent to produce a displaced image of distant objects or the sky. The word comes to English via the French mirage, from the Latin mirare, meaning ‘to appear, to seem’. This is the same root as for mirror. Like a mirror, a mirage shows images of things which are elsewhere. The principal physical cause of a mirage, however, is refraction rather than reflection. For more details see the links to the left. Sources: http://wiki.answers.
Edwin Meyer, a physics professor at Baldwin-Wallace College, explains. To understand how a mirage forms, one must first understand how light travels through air. If the air is all the same temperature–cold or hot–light travels through it in a straight line. If a steady temperature gradient exists, however, light will follow a curved path toward the cooler air. The standard freshman physics explanation for this phenomenon is that cold air has a higher index of refraction than warm air does. As a result, photons (particles of light) travel through hot air faster than they can through cold air because the hot air is less dense. The quantum electrodynamics explanation is that photons always take the path of minimum time when traveling from one point to another. In order to get from one point to another in a minimum time, photons will take “shortcuts” even though the length of the path is curved and it covers a longer distance than the direct route. Mirages are a direct result of photons
Imagine a wanderer in the desert, dying of thirst. He looks off into the distance and sees a vision of a pool of clear water surrounded by trees. He stumbles forward until the vision fades and there is nothing but hot sand all around him. The lake he saw in the distance was a mirage. What caused it? A mirage is a trick nature plays on our eyes because of certain conditions in the atmosphere. In a desert, there is a layer of dense air above the ground that acts as a mirror. An object may be out of sight, way below the horizon. But when rays of light from it hit this layer of dense air, they are reflected to our eyes and we see the object as if it were above the horizon and in our sight. We are really `seeing’ objects that our eyes cannot see! When the distanct sky is reflected by this `mirror’ of air, it sometimes looks like a lake, and we have a mirage.
