There is an urgent need for myths and legends about the Millennium vernal equinox.

Millennium is the first solar term in September. Dew is water droplets formed by condensation of water vapor on the ground or near-earth objects due to temperature drop. So the Millennium actually indicates that the weather is getting cold. At this time, people will obviously feel that the hot summer has passed and the cool autumn has arrived. Because the temperature is still more than 30 degrees during the day, but it drops to more than 20 degrees at night, and the temperature difference between them is 10 degrees. Yang Qi reached its peak in the summer solstice, and these two extremes must be reversed, and Yin Qi also rose at this time. When it comes to the White Dew, the yin gradually increases, and the morning dew gradually thickens and condenses into a layer of white water drops, so it is called the White Dew. As the saying goes, "eighteen pots of summer heat, not exposed to the Millennium." These two sentences mean that it is still hot in summer, so you must take a bath with a basin of water every day. After eighteen days, in the new millennium, don't be shirtless and naked, lest you catch cold. There is also a saying: "White dew and white fans, the autumn equinox is beautiful." This means that if there is dew before and after the white dew, the late rice will have a good harvest.

In ancient China, the autumnal equinox was divided into three periods: "When thunder comes, the sound will stop;" Second, wait for scorpion blank households; Wait for the water to dry. "The ancients thought it thundered because the sun be the spirit is strong, and the yin began to fill after the autumnal equinox, so it didn't thunder. 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. In most areas, the rainy season has just ended, with a cool breeze blowing gently, the sky is high and the clouds are light in Wan Liqing, the air is crisp in autumn, the sweet-scented osmanthus is fragrant, the crab is fat and the chrysanthemum is yellow, and the autumn equinox is a beautiful and pleasant season. It is also an important solar term in agricultural production. After the autumnal equinox, the direct sunlight 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 frost comes to the foot of the wild goose. "It's not surprising that the northeast cools down early and the autumnal equinox sees frost. From the day of the autumnal equinox, the climate has three main characteristics: the position of direct sunlight continues to move from the equator to the southern hemisphere, and the phenomenon of short days and long nights in the northern hemisphere will become more and more obvious. The days will gradually shorten and the nights will gradually lengthen (until the winter solstice reaches the longest night and the shortest day); The temperature difference between day and night will gradually increase, and the amplitude will be higher than 10℃. The temperature drops day by day, getting colder every day, and gradually entering the late autumn season. The situation in the southern hemisphere is just the opposite.