What is the formula of the twenty-four solar terms?

Spring rain shocks spring and clear valley days, summer is full of mountains and summer is connected with heat, autumn dew is cold and frost, and winter snow drifts.

The two festivals remain unchanged every month, with a maximum difference of one or two days. The first half of the year is June 2 1 day, and the second half is August 23.

"Twenty-four solar term song" was compiled according to the law of names for convenience of memory. There are 24 solar terms throughout the year, namely: beginning of spring, Rain, Sting, Vernal Equinox, Qingming, Grain Rain, Changxia, Xiaoman, Mangzhong, Summer Solstice, Xiaoshu, Dashu, beginning of autumn, Chushu, Bailu, Autumnal Equinox, Cold Dew, Early Frost, beginning of winter, Light Snow, Winter Solstice, Slight Cold, Heavy Snow.

In ancient China, agricultural irrigation depended on rivers, and agriculture was mainly concentrated in the Yangtze River and Yellow River basins. Until now, farmers in these areas are still engaged in agricultural production according to solar terms, temperature and precipitation.