Where is the direct sunlight on the winter solstice?

In winter, the solstice sun shines directly on the Tropic of Capricorn, with short days and long nights in the northern hemisphere, short days and short nights in the southern hemisphere, extreme nights in the Arctic Circle and extreme days in the Antarctic Circle.

Daily extreme value of geographical significance of winter solstice

According to modern astronomical science, the sun shines directly on the tropic of Capricorn (also known as the winter solstice daily line), and the sun is most inclined to the northern hemisphere, which has the shortest day and the longest night. After the winter solstice, the direct point of the sun slowly shifted to the Tropic of Cancer.

Lunar reference

In China's traditional theory of Yin-Yang and Five Elements, the winter solstice is the key solar term of Yin-Yang transformation. In the twelfth year, divination is a complicated divination in a mine, which is called the winter solstice. Yi Yue: My late king and even the Japanese were closed to the outside world, so business travel was no good. At the same time, the setting of leap month is also based on the winter solstice (because the winter solstice is always in the winter month, which is the first month of Zhou Zheng's lunar calendar).

From winter to the sun, the height of the sun is the lowest, the sunshine time is the shortest, and the heat absorbed by the ground is less than the heat lost. After the winter solstice, it begins to count to nine, and every nine days is a "nine". Before and after March 9th, the heat accumulated on the ground was the least, and the weather was the coldest, so it was said that it was cold on March 9th, and it was already January and February in the summer calendar, and most parts of our country had entered spring, so it was sunny on September 9th.

Angle knowledge

The polar axis passes through the center of the earth and connects the north and south poles. The included angle with the earth's orbit plane is 66.5, which is perpendicular to the equatorial plane of the earth's rotation orbit plane.

Introduction to Winter Solstice Winter Solstice, also known as Short Solstice, Winter Festival and Sub-year-old, 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. In ancient times, there was a saying that the winter solstice was as big as a year. The custom of winter solstice varies in content or details due to different regions. In southern China, there are customs of offering sacrifices to ancestors and enjoying the winter solstice. In northern China, it is a custom to eat jiaozi from winter to Sunday every year.

The winter solstice is the 22nd solar term in the "24 solar terms", and the solar calendar reaches 270 degrees. Every year, the festival is held on 65438+February 2 1-23 in the Gregorian calendar. The winter solstice is the limit of the sun's southward travel, and the height of the sun in the northern hemisphere is the smallest on this day. On the solstice of winter, the sun shines directly on the tropic of Capricorn, and the sun is most inclined to the northern hemisphere. The solstice in winter is the turning point of the sun's southward movement. After this day, I went back, and the direct point of the sun began to move northward from the Tropic of Capricorn (23 26' s), and the daytime in the northern hemisphere (China is located in the northern hemisphere) increased day by day.

In all parts of the northern hemisphere, the winter solstice has the shortest day and the longest night. The farther north, the shorter the day. Although the days from winter solstice are short, the temperature from winter solstice is not the lowest; It won't be very cold before the winter solstice, because there is still "accumulated heat" on the surface, and the real winter is after the winter solstice; Due to the great differences in climate in different parts of China, the climatic characteristics of this day are obviously late for most parts of China. The winter solstice marks the beginning of the cold season, and people begin to count to nine to calculate the cold weather (folk proverb: "The summer solstice is the third watch, and the winter solstice is the ninth watch").