Twenty-four formulas:

Spring rains startle spring and clear the valley, and summer is full of sunshine and summer is connected. Autumn is exposed, autumn is cold and frost, and winter snow is small and winter is cold.

it is the twenty-four solar terms of beginning of spring, rain, fright, vernal equinox, Qingming, Grain Rain, long summer, Xiaoman, Mangzhong, Summer Solstice, Slight Summer Heat, beginning of autumn, Chushu, Bailu, Autumn Equinox, Cold Dew, first frost, beginning of winter, Light Snow, Heavy Snow, Winter Solstice, Slight Cold and Severe Cold.

extended information

the 24 solar terms are divided according to the position of the earth on the ecliptic (that is, the orbit of the earth around the sun). Depending on the sun starting from vernal equinox (longitude zero, at this moment the sun shines vertically on the equator), every 15 degrees forward is a solar term; After a week's operation, I returned to vernal equinox, which is a tropical year, which is 36 degrees, so it is divided into 24 solar terms.

Reference: Baidu Encyclopedia-Twenty-four solar terms.