What are the solar terms behind the Millennium?

Behind the Millennium is the autumnal equinox solar terms.

The autumnal equinox is the sixteenth of the twenty-four solar terms, and the time is generally from September 22 to September 24 of the Gregorian calendar every year. On the day of the autumnal equinox, the sun reaches 180 (autumnal equinox), almost pointing to the equator of the earth.

Around the world, the length of day and night is equal (regardless of the refraction of the sun light by the atmosphere and the shadow in the morning). In ancient times, there was a folk activity of "offering sacrifices to the sun in spring and the moon in autumn". The autumnal equinox used to be the traditional "Moon Festival" (Mid-Autumn Festival), which evolved from offering sacrifices to the moon in autumn.

Extended data

According to the lunar calendar, "beginning of autumn" is the beginning of autumn and ends with "the first frost", and the "vernal equinox" is just half of the 90-day journey from beginning of autumn to the first frost. At the autumnal equinox, the Yangtze River basin and its vast northern area have entered autumn, and the daily average temperature has dropped below 22℃. The cold air mass in the north began to have some influence.

The rainy season has just ended in most areas, with a cool breeze blowing gently. Wan Li is blue, the weather is clear, the autumn air is crisp, the osmanthus fragrance is fragrant, the crab is fat and the chrysanthemum is yellow, and the autumnal equinox is a beautiful and pleasant season. It is also an important solar term in agricultural production. After the autumnal equinox, the direct point of the sun moved to the southern hemisphere, and the northern hemisphere got less and less solar radiation, while the ground lost more heat and the temperature dropped significantly.

Agricultural proverbs say: "An autumn rain is a cold", "The white dew is divided into autumn nights, and one night is cold". "In August, the wild goose gate opens, and the foot of the wild goose is frosty." It is not surprising that frost appears in the autumn equinox in a year when the temperature in Northeast China drops early. On the day of the autumnal equinox, the sun is located at the longitude of the yellow meridian 180 degrees, and the sunlight is almost direct to the equator, and the length of day and night in most parts of the world is almost the same.

At this time, the waiting temperature in the southern region has generally dropped below 22℃, and it has entered a cool autumn. "An autumn rain and a cold". The cold air from the south meets the warm and humid air that gradually decays, which leads to repeated rainfall and the temperature drops again and again. In the northern part of the northwest plateau, the daily minimum temperature has dropped below 0℃, and you can already see the magnificent snow scene flying all over the sky and the earth wrapped in silver.