Dongjie

The traditional Chinese calendar divides a year into 24 solar terms. Dōngzhì, Tōji, Dongji, Tunji, or Đông chí is the 22nd solar term, and marks the winter solstice. The term begins when the Sun reaches the celestial longitude of 270° and ends when it reaches the longitude of 285°. In common usage, Dongzhi more often refers to the particular day when the Sun is exactly at the celestial longitude of 270. In the Gregorian calendar, it usually falls between December 21 and December 23.

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