Winter Solstice

Winter Solstice (Dongzhi), also known as the Southernmost Sun, Winter Festival, and Ya Sui (Second New Year), is the twenty-second of the “Twenty-Four Solar Terms” and one of the earliest solar terms to be measured and recorded. It occurs when the Big Dipper points to the terrestrial branch zi and the sun reaches the ecliptic longitude of 270°, typically falling on December 21–23 in the Gregorian calendar.

Customs during the Winter Solstice vary. In the southern regions, there is a tradition of ancestor worship and feasting; in the northern regions, eating dumplings is the universal custom on the Winter Solstice. The origin of the Winter Solstice can be traced back more than 3,000 years. When the Duke of Zhou sought to select a capital city, he traveled across mountains and rivers to Luoyang. Using the tugui (gnomon) method, he “measured the depth of the earth, corrected the sun's shadow, sought the center of the land, and verified the four seasons.” He regarded Luoyang as the “center of all under heaven,” and took the day with the longest shadow as the day marking the start of the new year — this was the Winter Solstice. During the Zhou dynasty, the eleventh month of the lunar calendar was regarded as the first month (zhengyue), and the Winter Solstice was considered the first day of the new year, on which the new year was celebrated. The Liji·Xia Xiaozheng (Book of Rites: Lesser Annuary of the Xia) describes: “(In the eleventh month) the elaphure sheds its antlers; it is the Winter Solstice, and yang qi begins to stir.” Sima Qian's Shiji·Tianguan Shu (Records of the Grand Historian: Book of the Heavenly Offices) mentions: “At the beginning of the year, or on the day of the Winter Solstice, the generative qi first begins to sprout.” During the Han dynasty, the Winter Solstice was also called the “Winter Festival,” and the government would hold congratulatory ceremonies. During the Wei, Jin, and Six Dynasties periods, the Winter Solstice was known as “Ya Sui” (Second New Year), and the common people would bow and kneel before their parents and elders to express their gratitude. During the Tang and Song dynasties, the Winter Solstice was a day for offering sacrifices to heaven and ancestors; the emperor would conduct a grand heaven-worshipping ceremony in the suburbs, and the common people would worship their ancestors. In the Ming and Qing dynasties, the emperor also presided over the grand ceremony of sacrificing to heaven.

On the day of the Winter Solstice, the solar altitude is at its lowest and the duration of sunshine is at its shortest, signaling the imminent arrival of the cold season. Across much of northern China, the average temperature is generally below 0°C, while in most of the south it ranges between 6°C and 8°C. This period is an opportune time for constructing water conservancy works and for accumulating and preparing compost; all regions must take precautions against freezing. The Winter Solstice has three pentads: in the first pentad, earthworms coil; in the second pentad, the elaphure sheds its antlers; in the third pentad, water springs stir. This means that earthworms in the soil curl up their bodies, the elaphure senses the gradual retreat of yin qi and sheds its antlers, and springs in the mountains can still flow.