What determines the 24 solar terms?

The bucket handle of the Big Dipper points to the setting position of the sun.

The 24 solar terms reflect the wisdom of our ancient ancestors. Twenty-four solar terms played a very important role in ancient agricultural production. In the past, many farmers judged the harvest and planting time of crops through the 24 solar terms. We are also using 24 solar terms now, which are also of great significance to modern society.

The 24 solar terms are beginning of spring, Rain, Surprise, Equinox, Qingming, Grain Rain, Long Summer, Xiaoman, Busy, Summer Solstice, Slight Summer, beginning of autumn, Chushu, Millennium, Equinox, Cold Dew, First Frost, beginning of winter, Light Snow, Heavy Snow, Winter Solstice, Slight Cold and Severe Cold. Twenty-four solar terms were of great significance to agricultural development in ancient times. This is also one of the important reasons for the invention of the twenty-four solar terms.

Twenty-four solar terms are a time knowledge system formed by ancient Chinese people through observing and summarizing the annual movement of the sun. There are painting styles recorded in some ancient books, and three methods are mainly used in the 24 solar terms, namely, the method of shifting stars, the method of measuring shadows with standard tables and the method of Huang Chi intersection.