The traditional
Chinese lunisolar calendar
The traditional Chinese calendar, dating back to the Han dynasty, is a lunisolar calendar that blends solar, lunar, and other cycles for social and agricultural purposes. While modern China primarily uses the Gregorian calendar for officia ...
divides a year into 24
solar term
A solar term (or ''jiéqì'', zh, t=節氣, s=节气) is any of twenty-four periods in traditional Chinese lunisolar calendars that matches a particular astronomical event or signifies some natural phenomenon. The points are spaced 15° apart ...
s.
''Dàxuě'' () is the 21st solar term. It begins when the Sun reaches the
celestial longitude
In astronomy, coordinate systems are used for specifying positions of celestial objects (satellites, planets, stars, galaxies, etc.) relative to a given reference frame, based on physical reference points available to a situated observer (e.g. ...
of 255° and ends when it reaches the longitude of 270°. It more often refers in particular to the day when the Sun is exactly at the celestial longitude of 255°. In the
Gregorian calendar
The Gregorian calendar is the calendar used in most parts of the world. It went into effect in October 1582 following the papal bull issued by Pope Gregory XIII, which introduced it as a modification of, and replacement for, the Julian cale ...
, it usually begins around 7 December and ends around 21 December (22 December East Asia time).
Pentads
*鶡旦不鳴, 'The jie-bird ceases to crow': the ''jie'' is a bird, similar to the pheasant, which is believed to be aggressive and combatant. As winter progresses, even this active bird slows and ceases to crow.
*虎始交, 'Tigers begin to mate'
*荔挺生, 'The litchi plant (tree) starts to germinate.'
Date and time
References
{{DEFAULTSORT:Daxue (Solar Term)
21
Winter time