When is the autumn equinox?

The sixteenth solar term in the twenty-four solar terms of the lunar calendar in the autumnal equinox is usually on September 23rd or 24th every year. The climate in the south began to decline from this solar term. First, the sun reaches 180 degrees on this day, pointing directly at the equator of the earth, so a day is divided into 24 hours, each 12 hours; There is no extreme day and night phenomenon in the world. After the autumnal equinox, the polar night range near the North Pole and the polar sun range near the South Pole gradually expanded. On September 23rd, 20 15, at 6: 06, 2 1, the "autumnal equinox" solar term officially ushered in, which means that it officially entered autumn.

China's ancient book "Spring and Autumn Stories, Yin and Yang in and out" said: "The autumn equinox, Yin and Yang are also half-phase, so it is cold and hot day and night." The autumnal equinox means "half"

The autumnal equinox "autumnal equinox" has two meanings: first, the time between day and night is equal, the day is long and the night is short, and the day is short and the night is long. On this day, the sun reaches longitude 180 degrees and points directly at the equator of the earth, so the 24 hours of this day are divided equally, each being 12 hours; There is no extreme day and night phenomenon in the world. Second, the climate changed from hot to cold. According to the division of seasons in ancient China, which began with beginning of spring, Changxia, beginning of autumn and beginning of winter, the autumnal equinox falls within 90 days of autumn and is divided equally in autumn.

The autumnal equinox is one of the 24 solar terms of traditional festivals in China. On September 22nd, 23rd or 24th of Gregorian calendar, the sun reaches 180 degrees. The meaning of the "twenty-four solar terms" in the autumnal equinox: "See the vernal equinox in mid-August". "Divide" means to divide day and night equally. Like the vernal equinox, the sun shines directly at the equator of the earth, and day and night are equal. Since then, the position of direct sunlight has moved south, and the days in the northern hemisphere have gradually shortened, the nights have become longer, and the temperature has dropped, which is of universal significance throughout the country. At the autumnal equinox, "fen" means "half". At the autumnal equinox, the world is as long as day and night.

After the autumnal equinox, the days are getting shorter and shorter in the northern hemisphere, and the nights are getting longer and longer in the southern hemisphere. The characteristics of the autumnal equinox The autumnal equinox solar terms are special among the 24 solar terms. The climate of the autumnal equinox At the autumnal equinox, most parts of China have entered a cool autumn. The cold air from the south meets the warm and humid air that gradually decays, resulting in continuous precipitation and the temperature dropping again and again. As people often say, it's time for "an autumn rain and a cold", but the daily precipitation after the autumnal equinox will not be great.

At this time, the field farming in the south and the north is different. In northern China, there is an agricultural proverb that says: "The white dew is early, the cold dew is late, and it is the right time to plant wheat in the autumn equinox." Proverbs clearly stipulate the sowing time of winter wheat in this area; And "White clouds come in autumn equinox, good songs and good rice seeds are everywhere" reflects the planting time of rice in Jiangnan area. In addition, the taboos of working people on the solar terms of the autumnal equinox are also summed up as proverbs, such as "the autumnal equinox is only afraid of lightning, and more meters are more expensive."