One day is the longest among the 24 solar terms.

In a year, the longest solar term in the southern hemisphere is (winter solstice), the shortest solar term is (summer solstice), and the solar terms with the same length of day and night in the world are (vernal equinox and autumn equinox).

This is based on the solar terms in the northern hemisphere. The "winter solstice" here means that the northern hemisphere is in the winter solstice solar term.

Winter solstice, also known as short solstice, winter festival, year-ending, winter worship, etc., has both natural and humanistic connotations. It is not only an important solar term among the 24 solar terms, but also a traditional folk festival in China. The solstice in winter is one of the eight festivals in four seasons, and it is considered as a big holiday in winter. There is an ancient saying that the solstice in winter is as big as a year, so the ancients called it "off-year" or "off-year".

This shows that the year is coming, and the second is the importance of the winter solstice. When the winter solstice arrives, the New Year is just around the corner, so the ancients thought that the winter solstice was as important as the New Year. Many places still maintain the traditional custom of offering sacrifices to heaven and ancestors from the winter solstice.

Extended data

The winter solstice, also known as the south solstice, is a solar term reflecting the direct sunlight movement. There is a saying that "the solstice in winter is a sunny day" (recorded in the manuscripts that abide by the Constitution). In fact, strictly speaking, "Yang" has the concepts of Yin and Yang and Yang of the sun. On the solstice after winter, the height at which the sun rises is not the yang spirit in the concept of "yin and yang".

The solar terms from the winter solstice reflect the deviation law of the direct sunlight point on the earth's surface. The arrival of the winter solstice solar terms shows that the height of the sun is the smallest and the day is the shortest in all parts of the northern hemisphere, which is not the day with the highest concept of yin and yang. "Yin-Yang and Five Elements" belong to the category of "trunk and branch", and the growth and decline of "Yin-Yang" is based on "trunk and branch". The solstice in winter is the starting point for the return of the sun. Since the winter solstice, the height of the sun has risen, and the days in the northern hemisphere are getting longer day by day. The "yang" reflected by the winter solstice is the sun's yang, not the yang in the concept of "yin and yang"