Why should the solar calendar be used in the twenty-four solar terms?

If we regard the earth as a fixed point and the sun as a moving point, then the orbit of the sun around the earth is what we often say. The ecliptic extends 9 degrees from north to south, and the constellation 12 on the ecliptic is what we often say.

According to the position of the sun on the ecliptic, the 24 solar terms are divided into 24 seasons, and the climate reflects the natural phenomena and seasonal characteristics of farming in a certain area of China (represented by the middle and lower reaches of the Yellow River). It is a supplementary calendar concluded by China to guide farming in ancient times, which was formed in the Spring and Autumn Period and the Warring States Period. Because the lunar calendar in China is a kind of "yin and yang calendar", which is based on the movement of the sun and the moon, it can't fully reflect the solar cycle. But China is an agricultural society, and agriculture needs a strict understanding of the movement of the sun, so farming is entirely based on the sun. Therefore, the "twenty-four solar terms" that reflect the solar cycle alone are added to the calendar as the standard for determining leap months. Twenty-four solar terms can reflect the changes of seasons, guide agricultural activities and affect the food, clothing, housing and transportation of thousands of families.

Some people think that the 24 solar terms are subordinate to the lunar calendar, but they are actually defined according to the solar calendar. That is, according to the position of the sun on the ecliptic, a year is divided into 24 equal parts. That is to say, the ecliptic is divided into 24 equal parts, each equal part accounts for 15 of the ecliptic. The trajectory of the earth's movement around the sun is an ellipse, similar to the outline of an egg. Xiaotou is called apohelion, which corresponds to the winter solstice, usually 65438+February 22nd. On the solstice in winter, the days are the shortest and the nights are the longest. After the winter solstice, the days get longer and the nights get shorter. The big head is called perihelion, which is equivalent to the summer solstice in mid-air. Generally, it is June 22nd, with the longest day and the shortest night. The summer solstice is the extreme of yang, and the winter solstice is the extreme of yin. After the winter solstice, a yang is born, and after the summer solstice, a yin is born.

The lunar calendar reflects the law of the moon's orbit around the earth. Let me add that not only the 24 solar terms are marked according to the solar calendar, but also the fortune-telling horoscope is marked according to the solar calendar. In the past, fortune-telling was always reported to the lunar calendar, because many people memorized the horoscope. I remember that the daily column on a certain day every month is pushed back and forth, called "Meteor Rush".