A rainbow is a multicolored arc made by light striking water droplets.
A rainbow is not located at a specific distance from the observer, but comes from an optical illusion caused by any water droplets viewed from a certain angle relative to a light source.
They are the result of the refraction and reflection of light.
Light entering a water droplet is refracted. It is then reflected by the back of the droplet.
Sir Isaac Newton discovered the seven distinct colors of the visible spectrum.
The order of the Rainbow spectrum is red, orange, yellow, green, blue, indigo, violet.
But there aren’t really seven colors in a rainbow, nor any particular number. Each “color” shades imperceptibly into the next with no hard boundary other than those imposed by human observers of different cultures.
The most familiar type rainbow is made when sunlight strikes raindrops in front of a viewer at a precise angle of 42 degrees.
Rainbow actually occurs as a full circle, but since we watch it from ground it appears as an arc.
Viewers in aircraft can sometimes see these circular rainbows.
Rainbows can also be viewed around waterfalls, sea spray and geysers.
If there is a double rainbow the colors of a secondary are in opposite order of the primary or first rainbow.
Third and fourth and even multiple bows can sometimes be seen.
Unlike a double rainbow that consists of two separate and concentric rainbow arcs, the very rare twinned rainbow appears as two rainbow arcs that split from a single base.
A Monochrome or Red Rainbow is a very rare variation of rainbow. Normally observed at either sunrise or sunset, a Monochrome requires a particular combination of atmospheric conditions to form.
Upside down rainbows or cirumzenithal arcs can sometimes occur they are also known as sun smiles. They form when the sunlight reflects through ice crystals.
A supernumerary rainbow—also known as a stacker rainbow—is an infrequent phenomenon, consisting of several faint rainbows on the inner side of the primary rainbow, and very rarely also outside the secondary rainbow. Supernumerary rainbows are slightly detached and have pastel colour bands that do not fit the usual pattern.
A moonbow or lunar rainbow is a rainbow produced by light reflected by the Moon.
Fogbow a phenomenon similar to a rainbow, produced by sunlight shining on fog.
Earth is the only planet in the solar system where rainbows are possible.
The moist atmosphere of Titan, Saturn’s moon is ideal for formation of rainbow.
René Descartes was first who realised in 1637 that rainbows were caused by light from the sun being split into different colours by rain.
No one sees the same rainbow—each person has a different antisolar point, each person has a different horizon.
In today culture it is considered lucky to look at a rainbow and it is known as a symbol of renewed hope.
Rainbows have relaxing and healing qualities.
Rainbow occur in Genesis 9, as part of the flood story of Noah, where it is a sign of God’s covenant to never destroy all life on earth with a global flood again.
Another ancient portrayal of the rainbow is given in the Epic of Gilgamesh: the rainbow is the “jewelled necklace of the Great Mother Ishtar” that she lifts into the sky as a promise that she “will never forget these days of the great flood” that destroyed her children.
Rainbows are part of the myths of many cultures around the world.
In Norse mythology, the rainbow bridge Bifröst connects the world of men (Midgard) and the realm of the gods (Asgard).
The Irish leprechaun’s secret hiding place for his pot of gold is usually said to be at the end of the rainbow.
In Greek mythology Iris was believed to come with the rainbow as a bridge between the heavens and earth.
Also in Greek mythology, Iris is the personification of the rainbow and messenger of the gods.
In the ancient beliefs of Japan and Gabon, rainbows were the bridges that human ancestors took to descend to the planet.