What are the 24 solar terms?

In essence, solar terms belong to the solar calendar. From the astronomical point of view, the 24 solar terms are divided into 24 equal parts according to the earth's orbit around the sun (ecliptic) of 360 degrees, and spring is divided into zero points. Every two bisectors are separated by 15 degrees, and each bisector has a proper name, which contains the significance of climate change, phenological characteristics and crop growth.

Twenty-four solar terms have been gradually established and improved in China. During the Zhou Dynasty and the Spring and Autumn Period in China, the summer solstice, winter solstice, vernal equinox and autumn equinox were determined by measuring the sun's shadow with soil gauge. The number of solar terms recorded in Lv Chunqiu in Qin Dynasty has increased to eight, namely, beginning of spring, vernal equinox, long summer, summer solstice, beginning of autumn, autumn equinox, beginning of winter and winter solstice. There are also some records about the germination of solar terms, such as fright, rain, slight summer heat, Millennium and first frost. By the Han Dynasty, Huainanzi Astronomical Training had a complete record of 24 solar terms, exactly the same as today.