It is always a nice treat to see a rainbow and a double rainbow is an added bonus. A rainbow is an optical and meteorological phenomenon that is caused by reflection of light in water droplets in the Earth’s atmosphere, resulting in a spectrum of light appearing in the sky.
In a “primary rainbow”, the arc shows red on the outer part and violet on the inner side. This rainbow is caused by light being refracted while entering a droplet of water, then reflected inside on the back of the droplet and refracted again when leaving it.
In a double rainbow, a second arc is seen outside the primary arc, and has the order of its colours reversed, red facing toward the other one, in both rainbows. This second rainbow is caused by light reflecting twice inside water droplets.
Double Rainbow
Great picture of the double rainbows.