On the evening of July 15th, I spotted a colorful cloud next to the sun. Because the sun is just blocked by a building, the color of the clouds is relatively obvious and bright. It has many and special colors, besides red and yellow, there are also rare green and blue purple in the sky. This is iridescent clouds, which are the result of sunlight diffracting through water droplets to form various colors. Because of the strong wind, the iridescent clouds disappeared like a flash in the pan, but they were impressive.