How many rainbows are there in a day

Rainbows are more common in mornings and evenings. To form a rainbow, sunlight needs to strike a raindrop at around 42 degrees. That's unlikely to happen if the sun is higher than 42 degrees in the sky , according to the website of the National Oceanic and Atmospheric Administration NOAA. Rainbow over St Paul's Cathedral and the city of London. But rainbows that do appear after dark are called moonbows. That makes sense, because the light rays being bent come from reflections off the moon instead of directly from the sun.

A lunar rainbow at Victoria Falls in Zambia. The constellation Orion is visible behind the top of the moonbow.

The light bouncing off certain raindrops for your rainbow is bouncing off other raindrops from a completely different angle for someone else, according to LiveScience. And so it's creating a different image -- basically, no two people can stand in the same exact spot at the same time to view the same rainbow.

As this reflected light is leaving the water, it's refracted again at several angles [source: National Geographic ]. You'd think we mortals would know everything about rainbows, as popular as they are. Yet there are actually quite a few myths out there about these multihued illusions.

Think you're pretty rainbow-savvy? Here's betting you learn at least one new fact about them by the time you finish this article. Our first rainbow myth is probably the most famous.

One of the most storied rainbow myths is that there's a pot of gold at the end of every one. Not only that, but that the pot of gold is guarded by a tricky leprechaun. The legend goes like this:. Once upon a time, the Vikings lived in Ireland, looting and plundering as they pleased, then burying their ill-gotten treasures all over the countryside.

When they eventually departed from the Emerald Isle, they inadvertently left behind some of their booty, which the leprechauns found. Now, the leprechauns knew the Vikings had gotten their treasures through stealing, which was wrong. This bad behavior made the leprechauns mistrust all people, Viking or not. In order to ensure no humans could take what they now considered their gold, the leprechauns reburied it in pots deep underground all over the island. When rainbows appear, they always end at a spot where some leprechaun's pot of gold is buried [source: Mystical Myth ].

Here's the catch: Believers who've searched for the legendary pot o' gold always end up stymied, because they can never find the rainbow's end. The reason for that is on the next page. It's true rainbows appear to form perfectly rounded arches. But in reality, rainbows form full circles. Then why don't we see circles? When we're standing on the ground, we can only see light that's reflected by raindrops above the horizon. Thus, we can't see a rainbow's lower, hidden half. There is one way you may be able to see a full-circle rainbow, though.

If you're a pilot or passenger in an airplane or helicopter — and thus can see below the horizon — you might see a rainbow as a full circle. Sometimes people climbing tall mountains can view circular rainbows as well [sources: National Geographic ]. Since a rainbow is a circle you'll never reach the end or the bottom.

Rainbows seem to move when you do, because the light that forms the bow is always at a specific distance and angle from you [source: Howard ]. Remember we said earlier that rainbows were optical illusions? That's why you'll never find your pot of gold, alas.

This is an interesting "myth," because depending on how you look at it, it can be considered a true or false statement. In school you probably learned that the colors of the rainbow are in order red, orange, yellow, green, blue, indigo and violet. These are actually the colors of the visible spectrum. Red has the longest wavelength and violet the shortest. Some scientists think indigo is so similar to blue that it's indistinguishable for most people [source: National Geographic ].

But those seven hues are not the only ones in the world, of course. Where's the pink, for example? Or brown? Or sage, aqua, celadon and coral? Those colors, and more, are actually there in the rainbow. They're just invisible.

Rainbows contain upward of 1 million colors — that's right, 1 million — in a much larger continuum than the seven measly ones with which we're familiar [source: Howard ]. Unfortunately, our human peepers can't see all of those other hues.

So does this mean rainbows contain them or not? That's for you to debate. One of the more fascinating facts about rainbows is that no two people can see the exact same rainbow. Moonlight is reflected sunlight, as well as some starlight and " Earthlight. Rainbows are part of the myth s of many cultures around the world. Rainbows are often portrayed as bridges between people and supernatural beings. In Norse mythology , for instance, a rainbow called the Bifrost connects Earth with Asgard, where the gods live.

In the ancient beliefs of Japan and Gabon, rainbows were the bridges that human ancestor s took to descend to the planet. The shape of a rainbow also resembles the bow of an archer. Hindu culture teaches that the god Indra uses his rainbow bow to shoot arrows of lightning. Rainbows are usually positive symbols in myths and legends. In the Epic of Gilgamesh and, later, the Bible, the rainbow is a symbol from a deity the goddess Ishtar and the Hebrew God to never again destroy the Earth with floods.

Sometimes, however, rainbows are negative symbols. In parts of Burma, for instance, rainbows are considered demon s that threaten children. Tribes throughout the Amazon basin associate rainbows with disease. Perhaps the most famous piece of mythology surrounding rainbows is the Irish legend of the pot of gold at the end of a rainbow. The gold is guarded by a tricky leprechaun , but—because no one sees the same rainbow and rainbows don't "end" they're circles —no one ever finds the gold or the magical creature.

Rainbow flags usually appear as stripes bands of at least five different colors. Rainbow flags have long represented groups championing diversity , respect, and inclusive ness. The Wiphala is a type of rainbow flag. It is a symbol of communities indigenous to the Andes Mountains, stretching from modern-day Ecuador to Chile.

A Wiphala has been an official flag of Bolivia since , when the nation elected its first indigenous president, Evo Morales. The Wiphala features a diagonal patchwork design with squares in different rainbow colors.

Different arrangements of patchwork squares represent different Andean communities. The Buddhist flag, designed in the 19th century, is flown by Buddhist s around the world. It is a vertical arrangement of six bands, each representing a different aspect of Buddhism, from kindness to moderation, blessings to wisdom.

The Jewish Autonomous Oblast, a community on Russia's border with China, is represented by a seven-banded rainbow flag. The seven bands symbolize the seven branches of a menorah. The most familiar rainbow flag may be the banner representing the movement supporting civil rights for members of the lesbian, gay, bisexual, and transgender LGBT community.

The different colors of the "LGBT pride" flag represent the diverse community itself, as well as different aspects associated with each color. Orange, for example, symbolizes health and healing, while green symbolizes nature. Indigo also refers to the color and dye itself.

The refractive index of a substance is equal to the ratio of the velocity of light in a vacuum to its speed in that substance. Because this scattering is a geometric effect that depends on the direction of the original incoming sunlight, the rainbow forms as a circle or part of a circle that is centered on the point exactly opposite of the sun.

The main rainbow called the "primary rainbow" involves sunlight entering the raindrop, reflecting once off the inner back surface of the raindrop, and then exiting the raindrop. Additionally, light can bounce twice off the inner surface of the raindrop before exiting. The second reflection causes these light rays to exit at an angle that is very different from that of the light rays that only reflect once.

Therefore, a secondary rainbow forms that has a larger radius than the primary rainbow. The secondary rainbow is created by the same sunlight and the same refraction process as the primary rainbow, so it is also centered on the point exactly opposite the sun.

Because of the additional reflection, the colors in the secondary rainbow are reversed in order compared to the primary rainbow. Since some light is lost out of the raindrop with every reflection, the secondary rainbow is much fainter than the primary rainbow. In principle, the secondary rainbow is always present.