Mirages are most common in deserts. They happen when light passes through two layers of air with different temperatures. The desert sun heats the sand, which in turn heats the air just above it. The hot air bends light rays and reflects the sky. A uniform medium is the same everywhere from its top boundary to its bottom boundary and from its left boundary to its right boundary. But not every medium is a uniform medium, and the fact that air can sometimes form a non-uniform medium leads to an interesting refraction phenomenon - the formation of mirages.
A mirage is an optical phenomenon that creates the illusion of water and results from the refraction of light through a non-uniform medium.
Mirages are most commonly observed on sunny days when driving down a roadway. As you drive down the roadway, there appears to be a puddle of water on the road several yards maybe one-hundred yards in front of the car.
Of course, when you arrive at the perceived location of the puddle, you recognize that the puddle is not there. Instead, the puddle of water appears to be another one-hundred yards in front of you.
You could carefully match the perceived location of the water to a roadside object; but when you arrive at that object, the puddle of water is still not on the roadway. The appearance of the water is simply an illusion. Mirages occur on sunny days. The role of the sun is to heat the roadway to high temperatures. This heated roadway in turn heats the surrounding air, keeping the air just above the roadway at higher temperatures than that day's average air temperature.
Save my name, email, and website in this browser for the next time I comment. This site uses Akismet to reduce spam. Learn how your comment data is processed. How do mirages form? Where can you spot a mirage? Leave a Reply Cancel reply Your email address will not be published. Previous Previous post: National Bubble Week. But not every object you see is located directly along the direction in which you see it. Perhaps you have been frustrated by reaching into the surf for a smooth pebble resting on the bottom, only to close your fingers on a fistful of water.
Or tried over and over to scoop up a pesky leaf in your swimming pool, always missing it. The light reflecting off the pebble and the leaf changes direction as it exits the water.
Neither the pebble nor the leaf — nor the net at the end of the pole — is where you see it. You can experience a mirage as you drive. Some light is heading down toward the road in front of you. But the direction of that light can change as it travels through the air. The speed that light travels through a medium depends on its density.
Light goes slower through water, for example, then through air. And when light crosses a boundary from one medium to another, if the speed of the light changes, its direction changes as well.
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