The traditional Chinese calendar divides a year into 24 solar terms. XiÃÂohán, Shà Âkan, Sohan, or Tiá»Âu hàn () is the 23rd solar term. It begins when the Sun reaches the celestial longitude of 285ð and ends when it reaches the longitude of 300ð. It more often refers in particular to the day when the Sun is exactly at the celestial longitude of 285ð. In the Gregorian calendar, it usually begins around 5 January and ends around 20 January.