Find the vernal equinox, solstice winter and summer.

Vernal equinox-3/21; Summer solstice-June 22nd; Autumnal Equinox-September 23rd; Winter solstice-12/22.

During the spring equinox, China has entered a bright spring except the Qinghai-Tibet Plateau, Northeast China, Northwest China and North China. At this time, the climate is mild, the rain is abundant and the sun is shining, and the wintering crops in most parts of China enter the spring growth stage.

Summer solstice is a festival in the ancient folk "four seasons and eight festivals". Since ancient times, there has been a custom of offering sacrifices to gods and ancestors to the Japanese. "Heaven and earth are the foundation of life; Ancestors are the foundation of class. " Heaven and earth are the foundation of life, ancestors are the foundation of life, and ancestor worship is the custom of inheriting filial piety. In addition, there are folk customs such as "avoiding summer and hiding" and "clearing the field" from summer to Japanese.

Extended data:

"Twenty-four solar terms" is the product of ancient farming civilization, and farming production is closely related to the rhythm of nature. It is a knowledge system formed by ancient ancestors who followed the farming season and realized the changing laws of time, climate and phenology in a year by observing the movement of celestial bodies.

The ancient solar terms were established on the basis of "changing stars" (referred to by bucket handle), but now the solar terms are established on the basis of "the annual apparent movement of the sun" (the degree of the yellow meridian); Although the two methods are different, the cause of the struggle is actually that the earth revolves around the sun, so the intersection time of the two methods is basically the same.