About the origin of the 24 solar terms and its related knowledge?

Twenty-four solar terms originated in ancient times and were determined by the bucket handle direction of the Big Dipper. Bucket handle revolves around the east, south, west and north, which is called one of the "years" (Figure); Every rotation cycle starts from beginning of spring and ends with the Great Cold.

Development and evolution

First, the bucket handle points to

In ancient times, bucket handle's direction-the Big Dipper was used as the standard to judge the season, which was called sword fighting, also known as Jian Yue. Bucket handle turns to the 12th, which is called the "December Tower" (or "December Order"), and the "Building" represents the direction of the top of the bucket handle of the Big Dipper.

Second, the flat gas method

In the Western Han Dynasty, the name of "Twenty-four solar terms" first appeared in the book Huainanzi Astronomical Training. During the period of Emperor Wu of the Han Dynasty, "Twenty-four solar terms" were absorbed into taichu calendar as a supplement to the calendar guiding agriculture. Solar terms are divided by "flat gas method"

The date of each solar term divided by the method of flat gas is the same, and each month is divided into two sections, the first section is called "Festival" and the middle section is called "Qi". A solar year is divided into seasons, knots, air and climate, 1 year =4 seasons = 12 knots = 12 air =72 climate.

Third, the fixed gas method

The current "twenty-four solar terms" come from the "Qi-fixing Law" formulated by western priests more than 300 years ago, while the "Li Shixian" formulated by western priests today is based on the return of the sun on the ecliptic.

That is to say, on a 360-degree circle "ecliptic" (the apparent path of the sun on the celestial sphere for one year), it is divided into 24 equal parts, each equal part is 15, and the spring is divided into 0-degree starting point (but beginning of spring is still used to ranking first), and arranged according to the degree of longitude.

Extended information 1. Value at purchase price

Twenty-four solar terms are the product of ancient farming civilization. It occupies an extremely important position in the traditional farming culture of China. It is the product of long-term observation and research on astronomy and meteorology by ancient people in China, and it contains the long-standing cultural connotation and historical accumulation of the Chinese nation.

In the twenty-four solar terms, there are not only phenological changes between cold and summer, but also changes in temperature and rainfall. Through it, the ancients can intuitively and clearly understand the changing law of seasonal climate in a year, so as to master the farming season and arrange farming activities reasonably. It not only plays a guiding role in agricultural production, but also affects the food, clothing, housing and transportation of ancient people, and even cultural concepts.

Second, the date calculation formula

General formula of longevity -[y× d+c]-l

Y= the last two digits of the year, D=0.2422, L= the number of leap years, and C depends on the solar terms and year.

265438+20th century beginning of spring c value =3.87.

For example: beginning of spring date 20 17.

[ 17×0.2422+3.87]-[( 17- 1)/4]=7.9874-4=3

So the beginning of spring date of 20 17 is February 3rd.

Three or twenty-four solar terms

The rain in beginning of spring is falling, the insects are awake, the vernal equinox is near Qingming, and tea picking is in front of Grain Rain;

The long summer is small and satisfying, the awn is big and sickle-shaped, and there is only a little summer heat on the summer solstice, which lasts for three days;

Beginning of autumn is in summer, the white dew flies south, the autumn equinox is cold, and the first frost dyes the red leaves;

There is light snow in early winter, and heavy snow indicates a bumper year. The winter solstice lasts for nine days, with slight cold and severe cold.

Baidu encyclopedia-24 solar terms

Baidu Encyclopedia-24 solar term song