Why is the 22nd of every year the winter solstice? ......

The solstice in winter is not always the 22nd.

Every winter solstice is 65438+February 2 1 or 22 or 23. The current "twenty-four solar terms" come from the "fixed gas law" concluded more than 300 years ago. "Constant gas method" is a method to determine solar terms according to the position of the sun on the regression ecliptic, that is, 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, with one equal part for each 15.

The starting point is 0 degrees in spring (but beginning of spring is still ranked first in the ranking habit), and it is arranged according to the degrees of the Yellow Meridian. Every time the sun moves 15 degrees on the ecliptic, it is a "solar term", and each "solar term" has the same degree and different time.

Therefore, the 24 solar terms are 24 time points, and the specific date of the "point" is the natural result of celestial movement. The solar terms divided by the method of "fixing qi" began in the beginning of spring and ended in the great cold. The solstice in winter is when the sun moves to 270 degrees of the yellow meridian.

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Winter solstice custom

north

In many parts of northern China, it is a custom to eat jiaozi every winter solstice. According to legend, Zhang Zhongjing, a medical sage, saw a frozen person when he retired in his later years, so he wrapped mutton, some cold-dispelling herbs and dough into the shape of ears, made a medicine called "Quhan Jiaoer Decoction" and gave it to the people. Later, on the solstice of winter, people imitated eating and formed a custom.

south

Many places in southern China will celebrate the winter solstice. Some coastal areas in the south continue the traditional custom of ancestor worship. Every household is dedicated to ancestor statues, memorial tablets, etc. Go to the hall at home, place an altar, set up incense burners, offerings, etc. In some places, while offering sacrifices to ancestors, they also offer sacrifices to gods, land gods and deities, so as to make the next year's weather favorable and the family prosperous.

Baidu encyclopedia-winter solstice