Beginning of autumn's related knowledge

1, beginning of autumn, is 13 of the 24 solar terms and the first solar term in autumn, which falls on August 7-9 of the Gregorian calendar every year. At this time, the bucket handle of the Big Dipper points southwest, and the sun reaches longitude 135. The twenty-four solar terms reflect the changes of "Qi" in the four seasons. Beginning of autumn is the node where the yang gradually closes, the yin gradually grows, and the yang gradually turns to yin. Beginning of autumn, which also means precipitation and humidity, is at the turning point of the year, with a downward or decreasing trend; In nature, everything begins to grow from lush to mature.

Beginning of autumn doesn't mean the extreme hot weather is over. Beginning of autumn is still in the summer heat period, and the summer heat will not come out until the second solar term in autumn, and the weather is still very hot in early autumn. The so-called "heat is in the dog days" is also called "beginning of autumn drops later", and there is at least "falling" hot weather after beginning of autumn. According to the calculation method of "dog days", the days of "beginning of autumn" are often in the middle of dog days, that is to say, the heat is not over, and the real coolness usually comes after the Millennium solar terms. The watershed of summer heat is not in the solar terms in beginning of autumn.

Autumn is a season of alternating hot and cold. "Guanzi" said: "Autumn begins in the shade, so everything is harvested." After entering autumn, the climate changed from rainy and humid in summer to dry and rainy in autumn. In nature, the qi of yin and yang begins to change, the yang gradually closes, the yin gradually grows, and everything declines with the sinking of the yang. The most obvious change in autumn is that the leaves of vegetation change from lush green to yellow, and the leaves begin to fall and the crops begin to mature. Beginning of autumn is one of the "four seasons and eight festivals" in ancient times. People have the custom of offering sacrifices to the land gods and celebrating the harvest.