Rainbows are among the most magical – and fascinating – phenomenon that occurs in nature. No matter your age, it’s hard to look at a rainbow and not feel that sense of awe and wonder that you only get when you get to witness something truly special.
Rainbows have been considered good omens for thousands of years, and while there’s nothing wrong with hoping for a little luck at the sight of a rainbow, there’s some hard rainbow science that’s worth investigating, too!
Below, we’ve listed 8 amazing facts about rainbows that we hope you’ll find as interesting as we do!
1. You can never get to the end of a rainbow
If you’re the type who goes hunting for a pot of gold every time you see a rainbow, we can save you some trouble: you can never actually get to the end of a rainbow! Because a rainbow is based on the orientation of the observer (you) and the light source (the sun), when you move, the rainbow will move, too.
2. You can see a circular rainbow from the sky
While you’re on the ground, you can only observe the classic semi-circular rainbow (hence the word ‘bow’). However, when you’re flying in an airplane and looking down below, you can actually see a rainbow as a complete circle! If the weather circumstances are just right, of course.
3. You are less likely to see a rainbow in the winter
You are less likely to see a rainbow in the winter – but why? Because of snow! A rainbow is the result of light passing through a spectrum – in most cases, a collection of raindrops – and, therefore, having that light broken up and refracted into individual colors.
In the winter months, however, temperatures in the upper atmosphere drop to freezing, causing the raindrops to freeze into snow. This blocks the light from passing through the drop (or the snowflake) and prevents the appearance of a rainbow.
4. A double rainbow appears when light is reflected twice in a raindrop
Have you ever caught a double rainbow? A double rainbow occurs when the light is reflected twice in the raindrop, and thus, you can see two distinct reflections that are coming from two different angles.
Next time you happen to see this super cool occurence for yourself, take note of this fact about double rainbows: the secondary rainbow – which will be a little bit higher and fainter in color than the primary rainbow – will actually have its colors reversed. Instead of the standard “Roy G. Biv” (for red, orange, yellow, green, blue, indigo, violet), you’ll see the colors as Vib G. Yor!
5. Earth is the only planet in the solar system with rainbows
Sure, Jupiter has constant hurricanes of gas and Mars may even have some frozen water … but Earth is the only planet in our solar system capable of creating rainbows – so far as we know. That’s because Earth is the only planet with consistent liquid precipitation and direct sunlight.
On the Saturn moon of Titan, scientists believe there may be liquid methane rainstorms, but the atmosphere is so hazy that it’s unlikely enough sunlight passes through the methane drops to create a rainbow.
Another fun fact: on the surface of Saturn itself, about 1,000 tons of diamonds rain from the sky every year!
6. The Greeks and the Romans believed rainbows to be a path from the gods
In ancient times, the Greek goddess Iris (Arcus, to the Romans) was personified by the rainbow, with many works of art actually depicting her taking the form of a rainbow.
According to Greek mythology, Iris, who is the female counterpart to the messenger god Hermes, would use her pitcher to scoop up water and bring it into the clouds in order to form a rainbow. Her rainbow then became a bridge between Mount Olympus, where the gods and goddesses lived, and the Earth.
Of course, in the centuries since, rainbow science has evolved – we know a rainbow isn’t actually a bridge between heaven and earth! But it sure makes for a great story.
7. The longest-observed rainbow lasted for nearly 9 hours
The average rainbow is observable for less than an hour. But in 2017, students and professors of the Chinese Culture University, located high in the mountains of Taipei, Taiwan, observed a rainbow for 8 hours and 58 minutes, from 6:57 am until 3:55 pm.
Prior to this event, the longest-lasting rainbow was seen over Sheffield, England in 1994. That rainbow, as documented by the Guinness Book of World Records, lasted from about 9:00 am to 3:00 pm.
8. No two people see the exact same rainbow
If you and a friend are standing next to one another looking at a rainbow, you’re still not seeing the exact same rainbow! That’s because a rainbow has not physical presence; a rainbow is a purely optical phenomenon, and its appearance – its precise shape, arc, and the width of its color bands – will be slightly different according to the eye of the beholder.
That means there's one more amazing fact about rainbows we could add to the list: every rainbow is unique to you!
Continue Your Study of Rainbows
At Rainbow Symphony, we make it easy for you to continue to study rainbows and indulge your curiosity about this wonderful gift from Mother Nature. Try a pair of our diffraction glasses to transform any light source into a spectacular array of rainbow color, set up one of our suncatchers in your kitchen or bedroom to wash your walls into rainbow color, or pick up some of our educational tools to teach your class more facts about rainbows. The possibilities – like the tail end of a rainbow – are endless!