Sunlight and colorful clouds appear in Beijing at the same time. How did this phenomenon come about?

There are three conditions for the formation of colorful clouds: sunny days, the distance between the clouds and the sun 10 to 40 degrees, and the clouds are thin clouds with uniform water droplets. Solar halo is the light of various colors in different directions when it enters the ice crystals in cirrostratus.

Solar halo, also called round rainbow, is an atmospheric optical phenomenon, which is formed by the refraction or reflection of ice crystals when sunlight passes through cirrostratus. When light enters the ice crystals in cirrostratus, it is refracted twice and dispersed into light of various colors in different directions.

Don't watch with the naked eye for a long time when the solar halo appears, so as not to burn your eyes. When it's going to rain, cirrus clouds like bird feathers often appear in the sky, and then a rainy cirrostratus appears in the air about 6 kilometers below the cirrus clouds. Due to the low temperature, the water droplets in the cloud become small ice crystals in the shape of hexagonal prisms. When the sun's light energy passes through the clouds, it will be refracted to small ice crystals. It seems that there is a circle around the sun, and the spectrum is from the inside out. This is a solar halo.