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The traditional Chinese calendar divides a year into 24 solar terms.Dàhán, Daikan, Daehan, or Đại hàn (Chinese and Japanese: 大寒; pinyin: dàhán; rōmaji: daikan; Korean: 대한; romaja: daehan; Vietnamese: đại hàn; lit. 'major cold') is the 24th solar term. It begins when the Sun reaches the celestial longitude of 300° and ends when it reaches the longitude of 315°. It more often refers in particular to the day when the Sun is exactly at the celestial longitude of 300°. In the Gregorian calendar, it usually begins around 20 January and ends around 4 February.