What is the basis for the division of the 24 solar terms?

24 solar terms is divided according to the earth's position on the ecliptic (the earth's orbit around the sun).

Introduction of solar terms

Solar terms are precious scientific heritages created by our Chinese ancestors after thousands of years' practice, and they are tools to reflect climate and phenology changes and master agricultural time. 24 solar terms is divided according to the earth's position on the ecliptic (that is, the earth's orbit around the sun).

One revolution of the earth around the sun is 360 degrees, with the spring as the starting point of 0 degrees, and each advance of 15 degrees is a solar term, for example, Qingming, Grain Rain, Changxia and Xiaoman correspond to 15 degrees, 30 degrees, 45 degrees and 60 degrees respectively. After running for a week, I returned to the vernal equinox, which is a tropical year, totaling 360 degrees, so it is divided into 24 solar terms.

The source of the twenty-four solar terms

Twenty-four solar terms are special festivals in the calendar to express the change of natural rhythm and establish "December architecture", which contains a long cultural connotation and historical accumulation and is an important part of the long history and culture of the Chinese nation. Four years old, three months in spring, summer, autumn and winter, two solar terms each month, each solar term has its own unique meaning.

Twenty-four solar terms accurately reflect the change of natural rhythm and play an extremely important role in people's daily life. It is not only a seasonal system that guides agricultural production, but also a folk system that contains rich folk customs.

"Twenty-four solar terms" is the product of ancient farming civilization. It is a knowledge system formed by ancient ancestors following the farming season and observing the movement of celestial bodies to understand the changing laws of seasons, climate and phenology in a year. The twenty-four solar terms were originally formulated according to the changes of stars. The Big Dipper rotates in a circle and bucket handle rotates clockwise, which is called one of the "years".

The current "twenty-four solar terms" are formulated according to the position of the sun on the return to the ecliptic, that is, the annual movement track of the sun is divided into 24 equal parts, each 15 is 1, and each 1 is a solar term, starting in beginning of spring and ending in severe cold.