1, in China mythology:

Nu Wa refined five-color stones to fill the sky, and the rainbow is the colorful light emitted by the five-color stones.

Rainbow (dragon), a kind of dragon.

In Greek mythology, Iris is the messenger of heaven and earth.

3. In Irish folklore, goblins put their treasures at the end of the rainbow.

4. In Nordic mythology, the Rainbow Bridge (Bifr? St) Connect the domain of the gods "Asgard" (Asg? Rd) and the human settlement "Middle Earth" (Midg? Rd)。 That is, the traffic fortress between God and mankind can come and go through the Rainbow Bridge.

In the Jewish and Christian classic Genesis, the Lord asked Noah to build an ark to avoid the flood. After that, the Lord God made a covenant with Noah and his descendants with a rainbow, and no more floods would destroy the world.

Extended data:

The principle of rainbow formation:

Rainbow is formed by the scattering and reflection of sunlight on spherical water droplets in the air. When sunlight enters the water drop, it will be incident at different angles at the same time and reflected at different angles in the water drop. The reflection of 40 to 42 degrees is the strongest, which produces the rainbow we see.

Because water has dispersive effect on light, the refractive index of light with different wavelengths is different. The refractive index of red light is smaller than that of blue light, and the deflection angle of blue light is larger than that of red light. Because light is reflected in water droplets, the spectrum seen by the observer is reversed, with red light at the top and other colors at the bottom.

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