Kaleidoscope Sky: Nature's Beautiful Optical Illusions (PHOTOS)

Discover Magazine has a gorgeous slideshow of the various tricks the atmosphere can play on us. Check out some sample pictures below (many more can be seen here.)

"You might remember this one from elementary school science class: negative charges accumulate in the lower parts of clouds; positive charges accumulate in the ground. When the voltage exceeds the air's capacity to insulate it - zap! This long, lone lightning bolt struck out across the Arizona sky near the Silverbell Mountains." (photo by Brian Mayeux)

"Don't believe the cartoons - mirages don't happen solely in the desert. Light bends anytime it passes through air, but when the air temperature caries dramatically over a short distance, causing it to have great fluctuations in density, it can bend light so much that a mirage occurs. This image is called a superior image because it makes the boat look taller than it actually is. And superior mirages always include a portion of the picture that's inverted, as you can see here." (photo by Pekka Parviainen)

"The refraction of sunlight usually makes the sun appear flatter or more oval on the horizon during sunsets. This sunset over the Pacific Ocean, photographed by the European Southern Observatory in Chile, is a more pronounced version of that visual effect. Refraction severely flattens the top of the sun, but its light is brighter because of a shorter trip through the atmosphere. The double sun seen below is called an inferior mirage. This is the most common type of mirrage, the one we see all the time on highways on hot days." (photo by Luc Arnold)