Is there only one kind of rainbow? The answer is no, there are many kinds of rainbows that many people do not know about. Primary rainbows, secondary rainbows, red rainbows, supernumerary rainbows, and cloud rainbows are all examples of the same phenomenon.
Rainbows develop when sunlight passes through falling raindrops. Each hue has a different wavelength, which slows and refracts a unique amount. This refraction is what causes the colors to separate and head in different directions, thus creating a beautiful arc across the sky. Rainbows are not always just half circles, though. They may form into a complete circle, but we are usually only able to see half of it, unless we are high enough to see the complete circle. There are also double rainbows, which are formed when there are two reflections inside a raindrop. The second rainbow is much fainter than the original rainbow.
Fogbows seem like ghostly cousins of rainbows. While they are formed in the same way as rainbows, fogbows tend to be very difficult to find. If someone finds one, they are most likely inside of the fog. Like rainbows, fogbows are always opposite of the sun. However, fogbows are caused by small droplets inside a fog or cloud rather than by larger droplets. They do not happen everywhere on Earth, only in specific locations where fog is common.
Rainbows can emerge at night as well, but they are then called moonbows. These do not consist of sunlight, instead they use the illumination of the moon. Moonbows are most likely to occur during a full moon.
To see a rainbow, you must have the sun shining behind you and water droplets in front of you. You can also make your own rainbow at home! The two materials you will need are a hose that can spray water and a warm, sunny day. For step one, stand near the spray of water drops with your back facing the sun. Find your shadow; it is supposed to be in between you and the spray. If you can not find your shadow, move around until you do. Step two is to look for a rainbow in the spray. If the rainbow is not visible, you can look for the shadow of your head during step three. Hold both your arms straight in front of you. Spread your hands as wide as possible with your thumbs touching, tip to tip. Place the tip of one of your fingers so that the shadow falls in the center of the shadow of your head. Lastly, keeping that finger in place, look at the sunlit drops that line up with your finger. You should see a rainbow there!
[Sources: Sciencenewsforstudents.org; Home Science Tools]