Chinese calendar

The Chinese calendar is a lunisolar calendar formed by combining a purely lunar calendar with a solar calendar. Among Chinese, the calendar is not used for most day to day activities, but is used for the dating of holidays such as Chinese New Year and the Mid-Autumn Festival[?] and for divination. The primary use in day to day activities is for determining the phase of the moon, which is important for farmers and is possible because each day in the calendar corresponds to a particular phase of the month.

Ironically, the Chinese do not use the terms Chinese and Western calendar in Chinese. The Chinese name for the Chinese calendar is the farmer's calendar, and the Chinese name for the Western calendar is the civil calendar.

Table of contents 1 Calculations and Rules 2 Nomenclature 3 Twelve Animals 4 Jie Chi 5 Holidays

Calculations and Rules

The Chinese lunar calendar and the Julian Calendar often sync up every 19 years. Most Chinese people notice that their Chinese and Western birthdays often fall on the same day on their 19th, 38th birthday etc

The following rules for the Chinese Calendar (I believe) are equivalent to the rules as given by Helmer Alaksen. http://www.math.nus.edu.sg/aslaksen/calendar/chinese.shtml

These rules make use of the Tropical Zodiac familiar to Westerners. This must not be confused with the actual constellations corresponding to the 12 signs. The Chinese zodiac is completely different and is not used in the actual calculation of the calendar, but only in naming years. In fact, Chinese has a very different constellation system.

1. The months are lunar months, such that the first day of each month beginning 子时 (approximately 11 PM) is the day of the astronomical new moon.
2. Each year has 12 regular months, which are numbered in sequence (1 to 12). A year may also have an intercalary month (闰月), which may come after any regular month. It has the same number as the preceding regular month, but is designated intercalary.
3. The Chinese solar year (岁 sui4) is divided into 12 parts that are equivalent to the sun signs of the tropical zodiac.
4. Intercalary months are arranged so that, the sun always enters Capricorn on the 11th regular month (month 11) of a year.
5. If there are 12 months between two successive occurrences of month 11, one of these 12 months must be an intercalary month and it is the first of these 12 months during which the sun remains within the same zodiac sign throughout.
6. The times of the astronomical new moons and the sun entering a zodiac sign are determined in Chinese Time Zone by the Purple Mountain Observatory (紫金山天文台) in Nanjing.

The Zodiac Sign in which the sun is in at the start of the month usually determines the number of a regular month:

 Month  Zodiac Sign at Start
 11     Sagittarius (by rule 4)
 12     Capricorn
  1     Aquarius
  2     Pisces
  3     Aries
  4     Taurus
  5     Gemini
  6     Cancer
  7     Leo
  8     Virgo
  9     Libra
 10     Scorpio

Some astronomers believed this correspondence to be always true, but there are exceptions. An exception occurred in 1985, after the sun had entered Capricorn and then Aquarius in month 11, causing the Chinese New Year to occur on 20 February 1985 in Pisces rather than Aquarius.

The problem here is that there is a month in which the sun enters two signs of the zodiac. I'll refer to such a month as a dual-entry month. If a given month is a dual-entry month or has a dual-entry month before it and no earlier than the preceding month 11, the above correspondence may fail, otherwise it holds.

Nomenclature

The years are named by cycle of 10 Heavenly Stems (天干) and cycle of 12 Earthly Branches[?] (地支). Each year is named by a pair of one stem and one branch called Stem and Branch (干支). Heavenly Stems are associated with Yin Yang (阴阳) and 5 elements (五行). Earthly Branches are associated with 12 animals (see Twelve Animals section).

The 60-year cycle formed by combining the two cycles is known as a jiazi (甲子). It is not 120 because half of the combinations are unused. Jiazi is named after the first year in the 60-year cycle which is also called Jiazi. Some figures of speech use "jiazi" to mean "a full lifespan;" one who has lived more than a jiazi is obviously blessed. (Cf. the Biblical "three-score years and ten.")

This 60-year cycle is insufficient for historical references. During feudal China, the Nian Hao (Era name of an emperor) is add in front of year name for distinction. Example, 康熙壬寅 (kang1 xi1 ren2 yi2) (1662 AD) is the first 壬寅 (ren2 yi2) year during reign of 康熙 (kang1 xi1).

The months, day, and hours can also be denoted using Heavenly Stems and Earthly Branches, though they are commonly addressed using numerals instead. Together, the four Stem and Branch pairs form the Eight Characters (八字) used in Chinese astrology.

There is a distinction between solar year and lunar year in the Chinese calendar because the calendar is lunisolar. Lunar year (年 nian2) is from one Chinese new year to the next. Solar year (岁 sui4) is from one Start of Spring to the next (see Jie Chi section). Lunar year is used exclusively because dates are also in lunar.

Twelve Animals

The Twelve Animals (十二生肖 or colloquially called 十二属相) representing the 12 Earthly Branches (地支) are:

Rat

Ox

Tiger

Rabbit

Dragon

Snake

Horse

Sheep

Monkey

Rooster

Dog

Pig

This sequence is traditionally assigned according to a legend:

• One day, the twelve animals fought over the precedence of the animals in the cycle of years in the calendar. The Chinese gods held a contest to see which should be first: they all lined up on the bank of a river, and were given the simple task of getting to the opposite shore. Depending on arrival, the first to get there would get the first year, and the order would depend upon how fast they finished.

three versions

• So all the animals lined up on the river bank and they all jumped in. The rat snuck up and climbed on the ox's back. Just as the ox came ashore, the rat jumped off and finished the race first. The lazy pig came to the far shore last. And so the rat got the first year named after him, the ox got the second year, and the pig ended up as the last.
• According to Chinese legend, the twelve animals quarreled one day as to who was to head the cycle of years. The gods were asked to decide and they held a contest: whoever was to reach the opposite bank of the river would be first, and the rest of the animals would receive their years according to their finish.
• All the twelve animals gathered at the river bank and jumped in. Unknown to the ox, the rat had jumped upon his back. As the ox was about to jump ashore, the rat jumped off the ox's back, and won the race. The pig, who was very lazy, ended up last. That is why the rat is the first year of the animal cycle, the ox second, and the pig last animal in the year cycle.

See Chinese astrology for more details.

Jie Chi

Chinese months follow the phases of the moon. The part of the calendar that follows the movement of the sun is called Jie Chi (節氣 jie2 qi). Jie Chi is also translated to "Solar Terms". There are twenty four Jie Chi. These Jie Chi roughly fall on the same date in solar calendars such as Gregorian Calendar because they were solar based. Obviously these Jie Chi do not form any pattern in the Chinese calendar. Before the Gregorian calendar was introduced to China, these Jie Chi are published each year in farmers' almanac. Farmers relied on these Jie Chi to plan their planting and harvest.

Chinese Name	Occurrence (Gregorian Date)	Literary Meaning	Remark
立春 (li4 chun1)	February 4 ~ February 18	start of spring
雨水 (yu3 shui3)	February 19 ~ March 4	rain water	indicates more rain instead of snow
驚蟄 (jing1 zhe2)	March 5 ~ March 20	awakening of the insects	indicates animals and insects awakening from hibernation
春分 (chun1 fen1)	March 21 ~ April 4	vernal equinox
清明 (qing1 ming2)	April 5 ~ April 19	clear and bright	the time for tending graves
穀雨 (gu3 yu3)	April 20 ~ May 5	grain rain	indicates rain will help grain growth
立夏 (li4 xia4)	May 6 ~ May 20	start of summer
小滿 (xia3 man3)	May 21 ~ June 5	small plumpness	indicates plumpness of grains
芒種 (mang2 zhong4)	June 6 ~ June 20	grain in ear	indicates grains growing ears (botany usage)
夏至 (xia4 zhi4)	June 21 ~ July 6	summer solstice
小暑 (xiao3 shu3)	July 7 ~ July 22	minor heat
大暑 (da4 shu3)	July 23 ~ August 6	major heat
立秋 (li4 qiu1)	August 7 ~ August 22	start of autumn
處暑 (chu shu3)	August 23 ~ September 7	stop of heat
白露 (bai2 lu4)	September 8 ~ September 22	white dew	indicates condensed moisture makes dew white
秋分 (qiu1 fen1)	September 23 ~ October 7	autumnal equinox
寒露 (han2 lu4)	October 8 ~ October 22	cold dew
霜降 (shuang1 jiang4)	October 23 ~ November 6	frost descent	indicates appearing of frost and descent of temperature
立冬 (li4 dong1)	November 7 ~ November 21	start of winter
小雪 (xiao3 xue3)	November 22 ~ December 7	minor snow
大雪 (da4 xue3)	December 7 ~ December 21	major snow
冬至 (dong1 zhi4)	December 22 ~ January 5	winter solstice
小寒 (xiao3 han2)	January 6 ~ January 19	minor cold
大寒 (da4 han2)	January 20 ~ February 3	major cold

The dates above are approximate and may vary slightly year to year. Chinese New Year is usually the new moon day closest to Li Chun.

Song of Solar Terms is used to ease the memorization of Jie Chi.

Lyrics:

《节气歌》
春雨惊春清谷天，
夏满芒夏署相连，
秋处露秋寒霜降，
冬雪雪冬小大寒。

Holidays

Date	English Name	Chinese Name	Remarks	2003	2004	2005
month 1 day 1	Spring Festival (Chinese New Year)	春节		Feb 1	Jan 22	Feb 9
month 1 day 15	Lantern Festival[?]	元宵节	observed with yuanxiao eating	Feb 15	Feb 5	Feb 23
month 5 day 5	Dragon Boat Festival (Dragon Festival)	端午节	observed with dragon boat racing and zongzi eating	Jun 4	Jun 22	Jun 11
month 7 day 7	Qi Qiao Jie (Chinese Valentine's Day)	乞巧节	girls practice homemaking skills and 'beg' for good marriage	Aug 4	Aug 22	Aug 11
month 7 day 15	Spirit Festival (Ghost Festival)	中元节		Aug 12	Aug 30	Aug 19
month 8 day 15	Mid-autumn Festival[?] (Moon Festival)	中秋节	observed with family gathering and moon cake eating	Sep 11	Sep 28	Sep 18
month 9 day 9	Double Ninth Festival[?]	重阳节		Oct 4	Oct 22	Oct 11