You may think you know rainbows, but do you really know rainbows? HowStuffWorks.com is willing to bet you don't. We have more tidbits about refracted light than you've had hot meals, so step right up if you're feeling knowledgeable and prepare to get schooled in seven separate hues.
Rainbows are indeed visions but only illusions, or at least so sayeth the lyrics to "The Rainbow Connection," made famous by Kermit the Frog in 1979's "The Muppet Movie." We really hope you got that one right, because the questions are only going to get more difficult.
The musical's central fugitive plans to bury his treasure in the shadow of Fort Knox where he hopes it will grow into a golden harvest. Scientifically unfounded? Certainly, but the musical also features a scene in which a racist senator magically has his race changed, so it's probably best not to quibble about believability.
You'd be in Hawaii, which is also the home of the University of Hawaii Rainbow Warriors men's basketball team -- to say nothing of the state's wealth of actual rainbows.
Vishnu didn't need a rainbow sword. In Hinduism, it's said that his incarnation of Buddha was consumed by a giant sea creature known as the rainbow fish. Later, some fisherman caught the beast, freed Buddha and fed everyone for a year on the multicolored fish meat.
In addition to being the title of songs by both Boards of Canada and They Might Be Giants, Roy G. Biv is a mnemonic device for red, orange, yellow, green, blue, indigo and violet. While Aristotle also proposed a scale of seven basic colors, it was Newton who included indigo.
While some earlier theories involved rain clouds in the rainbow creation process, the answer is in fact raindrops. No leprechauns are harmed.
While we see one color refracted in each drop, every drop of water separates white light into all of the colors of the spectrum.
Rarely encountered at latitudes far from the Earth's poles, upside-down rainbows occur when sunlight shines through tiny ice crystals in high-altitude cirrus and cirrostratus clouds.
Yes, water droplets can refract the faint white light of the moon into a dim lunar rainbow. It appears to the human eye as a white arc, however, as we lose our light sensitivity in the darkness.
Saturn's moon Titan boasts both sunlight and water droplets, making rainbows a possible occurrence on the distant sphere.