Changes

==Characteristics of the Chinese calendar==

==Characteristics of the Chinese calendar==

The Chinese calendar, at least by the time it was adopted in Japan, was not an observational one ("There, we can see the new moon, so the month has started."), but a predictive one, based on calculations, as was necessary for a widely-spread out, developed bureaucracy. The calculation methods were revised at various times, both in China and Japan, so not everything below applies to all periods, especially the way of determining intercalary months.

The Chinese calendar, at least by the time it was adopted in Japan, was not an observational one ("There, we can see the new moon, so the month has started."), but a predictive one, based on calculations, as was necessary for a widely-spread out, developed bureaucracy. The calculation methods were revised at various times, both in China and Japan, so not everything below applies to all periods, especially the way of determining intercalary months. Further, as a result of Chinese and Japanese authorities performing their calendrical calculations separately, the Chinese and Japanese calendars often differed historically by a day or several.

The Chinese calendar is a lunar, actually a luni-solar, calendar. The start of the month is determined by the new moon, but the position of the month in the year is determined by the solar year, that is, course of the seasons. One should note that although in the the West seasons are considered to begin on the equinoxes and solstices, in the Chinese calendar, the start of spring (立春) is exactly half-way between the winter solstice and the spring equinox, and similarly for other seasons.

The Chinese calendar is a lunar, actually a luni-solar, calendar. The start of the month is determined by the new moon, but the position of the month in the year is determined by the solar year, that is, course of the seasons. One should note that although in the the West seasons are considered to begin on the equinoxes and solstices, in the Chinese calendar, the start of spring (立春) is exactly half-way between the winter solstice and the spring equinox, and similarly for other seasons.

*Months are either 29 (''Shô no tsuki'' 小の月) or 30 days (''Dai no tsuki'' 大の月) long.  This means that the date 2/30 is possible, whereas 3/31 is not.  Unlike some other calendars, it is  '''not''' the case that a particular month is normally a particular length. There is no way of knowing whether a month is 29 or 30 days long except by looking at the calendar for a particular year. Normally, but frequently not, 29-day and 30-day months alternate.  

*Months are either 29 (''Shô no tsuki'' 小の月) or 30 days (''Dai no tsuki'' 大の月) long.  This means that the date 2/30 is possible, whereas 3/31 is not.  Unlike some other calendars, it is  '''not''' the case that a particular month is normally a particular length. There is no way of knowing whether a month is 29 or 30 days long except by looking at the calendar for a particular year. Normally, but frequently not, 29-day and 30-day months alternate.  

*The calendar also takes into account the solar year. The solar year is divided into twelve periods by twelve solar points (中気　chûki) : the winter solstice, the spring equinox, the sumer solstice, the autumn solstice, and two points between each. <ref> The year is also divided into 24 "solar terms" (節気 ''sekki'') such as the "Great Cold."  These are the 12 chûki plus the 12 points that are half-way between chûki. </ref> The months are numbered according to the solar point that occurs during that month.  For example, the month in which the winter solstice occurs is the 11th month, and the one in which the spring equinox occurs is the 2nd month.

*The calendar also takes into account the solar year. The solar year is divided into twelve periods by twelve solar points (中気　chûki) : the winter solstice, the spring equinox, the sumer solstice, the autumn solstice, and two points between each. <ref> The year is also divided into 24 "solar terms" (節気 ''sekki'') such as the "Great Cold."  These are the 12 chûki plus the 12 points that are half-way between chûki. </ref> The months are numbered according to the solar point that occurs during that month.  For example, the month in which the winter solstice occurs is the 11th month, and the one in which the spring equinox occurs is the 2nd month.

*Because the lunar month is less than 1/12 of a solar year, sometimes a month falls entirely between the solar points  (中気). <ref>After 1844 the method of calculating the solar points changed, and there could be two in one month. In such cases the designations of the months were arranged so that the month with the winter solstice was the 11th month.</ref> In such cases the month is called an intercalary (閏 uruu) month, and is given the same number as the previous month. For more, see below on '''Intercalary Months'''.

*Because the lunar month is less than 1/12 of a solar year, sometimes a month falls entirely between the solar points  (中気). In such cases the month is called an intercalary (閏 uruu) month, and is given the same number as the previous month. For more, see below on '''Intercalary Months'''.<ref>After 1844 the method of calculating the solar points changed, and there could be two in one month. In Japan in such cases the months with the solstices and equinoxes were given their traditional month numberings, and the numbers of other months were arranged to fit.</ref>

*The first month (New Year) is the month that has the second solar point after the winter solstice. Thus New Year Day is usually the day of the new moon nearest to the first day of spring, about Feb. 4  (see above on the starts of seasons).  In the present Japanese modern lunar calendar, New Years Day is between about Jan. 21 and Feb. 19. <ref> Because both the western calendar and the Japanese calendar have changed in relation to the solar year over time, the possible dates vary with the period. For example, towards the end of the 16th century the new year started between Jan. 24 and Feb. 24.</ref> This means dates towards the end of the Japanese year are in the next year of the Western calendar.  For instance, the death of the [[Twenty-Six Martyrs of Japan]] was 1596/12/19, but it is better known by the Western date of Feb. 5, 1597.  The  [[Ako ronin|Akô rônin]] carried out their revenge on Genroku 15 (1702).12.15, which was Jan. 31, 1703 , so one sees both 1702 and 1703 as the date.

*The first month (New Year) is the month that has the second solar point after the winter solstice. Thus New Year Day is usually the day of the new moon nearest to the first day of spring, about Feb. 4  (see above on the starts of seasons).  In the present Japanese modern lunar calendar, New Years Day is between about Jan. 21 and Feb. 19. <ref> Because both the western calendar and the Japanese calendar have changed in relation to the solar year over time, the possible dates vary with the period. For example, towards the end of the 16th century the new year started between Jan. 24 and Feb. 24.</ref> This means dates towards the end of the Japanese year are in the next year of the Western calendar.  For instance, the death of the [[Twenty-Six Martyrs of Japan]] was 1596/12/19, but it is better known by the Western date of Feb. 5, 1597.  The  [[Ako ronin|Akô rônin]] carried out their revenge on Genroku 15 (1702).12.15, which was Jan. 31, 1703 , so one sees both 1702 and 1703 as the date.

   

   

===Intercalary Months===

===Intercalary Months===

As the solar year is about 365.25 days but 12 lunar months last only about 354, each year the months start about 11 days earlier with respect to the solar calendar (the seasons) as they did the previous year.  In fact, in about two years and eight months, the calendar moves a full month ahead.<ref> The Islamic calendar does not have intercalary months, so any given month changes its season year by year. There is no way of knowing the season of any month except by checking on a chart of that year.</ref> In order to keep the lunar and solar calendar from getting too far apart, as noted in the characteristics above, when the month gets a full month ahead,  the month is given the same number as the preceding month, but is called an "閏 (''uruu'')" month. For example, if there are two "third months," the first is called just "third month," but the next is called the "uruu third month". In this Wiki it is referred to as "'''int. 3'''", for "intercalary 3rd month".  Thus,  1599/3 was followed by 1599/int. 3, which was followed by 1599/4. This type of intercalary month, which can happen any month in the year, is a feature of the Chinese-type luni-solar calendar.

As the solar year is about 365.25 days but 12 lunar months last only about 354, each year the months start about 11 days earlier with respect to the solar calendar (the seasons) as they did the previous year.  In fact, in about two years and eight months, the calendar moves a full month ahead.<ref> The Islamic calendar does not have intercalary months, so any given month changes its season year by year. There is no way of knowing the season of any month except by checking on a chart of that year.</ref> In order to keep the lunar and solar calendar from getting too far apart, as noted in the characteristics above, when a month finishes too soon,  the month is given the same number as the preceding month, but is called an "閏 (''uruu'')" month. For example, if there are two "third months," the first is called just "third month," but the next is called the "uruu third month". In this Wiki it is referred to as "'''int. 3'''", for "intercalary 3rd month".  Thus,  1599/3 was followed by 1599/int. 3, which was followed by 1599/4. This type of intercalary month, which can happen any month in the year, is a feature of the Chinese-type luni-solar calendar.

==Calculation Website ==

==Calculation Website ==

Unlike conversions between era years and Western years, which is a fairly easy calculation (see [[Year dates]] and [[Japanese Eras]]), conversion between the Western and Chinese calendar can only be done using a monthly table based on historical documents. One table is Tuchihashi's.  However, now there are several websites that provide calculators which look up dates.  One is the following:

Unlike conversions between era years and Western years, which is a fairly easy calculation (see [[Year dates]] and [[Japanese Eras]]), conversion between the Western and Chinese calendar can only be done using a monthly table based on historical documents. One table is Tuchihashi's.  However, now there are several websites that provide calculators which look up dates.  One is the following:

http://www.uni-tuebingen.de/geschichte-japans/nengo_calc.htm which will give the Western year for the Japanese date.

http://web.me.com/meyer.eva/www.yukikurete.de/nengo_calc.htm which will give the Western year for the Japanese date.

Here are several notes on its use:

Here are several notes on its use:

*"Tsuchihashi" and "Zölner" are the authors of two calendrical tables.  For most years they are identical, but in some cases, especially for early years, they are not. To see the problem years use the "database" button and use the link given there.

*"Tsuchihashi" and "Zölner" are the authors of two calendrical tables.  For most years they are identical, but in some cases, especially for early years, they are not. To see the problem years use the "database" button and use the link given there.

*To use the calculator you have to know the nengô of the year.  An explanation of how to do this is found in Japanese eras and the Year dates pages. Or, even easier, run down the list of nengô in the pull-down menu on the calculator until  you find the period your year is in.  The year in the nengo system is [Western year] - [Nengo start year] + 1.    For example, 1600 is in the Keichô period, which started in 1596.  1600 - 1596 + 1 = 5, so 1600 is Keichô 5.  Unfortunately all numbers are in kanji, but you can easily learn the kanji or just count down on the pull-down menu. Note that the intercalary months are preceded by 潤.

*To use the calculator you have to know the nengô of the year.  An explanation of how to do this is found in Japanese eras and the Year dates pages. Or, even easier, run down the list of nengô in the pull-down menu on the calculator until  you find the period your year is in.  The year in the nengo system is [Western year] - [Nengo start year] + 1.    For example, 1600 is in the Keichô period, which started in 1596.  1600 - 1596 + 1 = 5, so 1600 is Keichô 5.  Unfortunately all numbers are in kanji, but you can easily learn the kanji or just count down on the pull-down menu. Note that the intercalary months are preceded by 閏.

*Before entering the month and day, the Western date shown is that of New Year Day of the Japanese year.

*Before entering the month and day, the Western date shown is that of New Year Day of the Japanese year.

*'''For dates Tenshô 10/9/18 (Oct. 4, 1582) and before, dates are in the Julian calendar, but from the next day,  Tenshô 10/9/19 (Oct. 15, 1582) the dates are the Gregorian calendar.'''

*'''For dates Tenshô 10/9/18 (Oct. 4, 1582) and before, dates are in the Julian calendar, but from the next day,  Tenshô 10/9/19 (Oct. 15, 1582) the dates are the Gregorian calendar.''' This change in the western calendar means you cannot just blindly use the program; you need to know which calendar to use for your western date.<ref>Catholic countries in Europe used the Gregorian immediately; some of Holland used it soon; the English changed in 1752; and Russia in 1918. Because of the distance from Europe, the Jesuits in Japan probably heard about the change in July 1585.

 

*From 1873 on, the Japanese dates are the Gregorian calendar.

*From 1873 on, the Japanese dates are the Gregorian calendar.

==References==

==References==

*[[Kojien Dictionary|''Kôjien Dictionary'']]

*[[Kojien Dictionary|''Kôjien Dictionary'']]

*http://www.uni-tuebingen.de/geschichte-japans/nengo_calc.htm

*http://web.me.com/meyer.eva/www.yukikurete.de/nengo_calc.htm

 

[[Category:Resource Articles]]

[[Category:Resource Articles]]