Introduction to the knowledge of Millennium solar terms

1, Bailu, is 15 of the "twenty-four solar terms", and the third solar term in autumn is the end of applying for the moon in the dry calendar and the beginning of the unitary month. Fighting fingers; The sun reaches longitude 165 degrees; Gregorian calendar September 7-9. "White dew" is an important solar term reflecting the growth of cold in nature. As the weather turns cold, it is sunny and hot during the day, but the temperature drops quickly after evening, and the temperature difference between day and night is large.

2. When it is white dew, the summer monsoon is gradually replaced by the winter monsoon, and the cold air turns to attack. In addition, when the direct point of the sun moves south, the sunshine time in the northern hemisphere becomes shorter, the light intensity weakens, and the ground radiation dissipates quickly, so the cooling speed gradually accelerates. The Millennium basically ended the sweltering heat in summer, and the weather gradually turned cold, and the cold gave birth to dew condensation. The ancients used four seasons to match five elements. Autumn belongs to gold, gold and white alternate with each other, and autumn dew is described in white, hence the name "White Dew".

3. According to the observation of nature, the ancients in China divided the Millennium into three stages: "When the geese come, the blackbirds return and the birds are ashamed." This means that in this solar term, migratory birds such as Hongyan and Swallow fly south to avoid the cold, and hundreds of birds begin to store dried fruit food for the winter. At present, farmers are also busy harvesting crops. As the saying goes, "If you grab autumn, you will lose it." During the Bailuyuan period, local folk customs mainly included offering sacrifices to Dayu, brewing grain wine and drinking Bailuyuan tea.