List of calendar systems
The following list of calendar systems is sorted according to what is the basis for determining the length of a calendar year . So there is:
- Astronomical calendars - are based on astronomical observations
- Arithmetic calendars - are based on arithmetic algorithms
- Changing year calendars - have a fixed number of days, the beginning of the year thus changes through the seasons
Depending on which astronomical observations are based on the length of the year, one differentiates:
- Solar calendar - according to the sun, more precisely the position of the sun (and thus the seasons , moon phases are not taken into account). The length of the year is the assumed mean distance between the points in time with the same position of the sun. The beginning of the year is either a certain position of the sun, usually the spring equinox , or an arbitrary day determined by arithmetic algorithms.
Lunar calendar - according to the moon, more precisely the moon phases . The year is defined as twelve months, the beginning of which corresponds to identical moon phases, mostly to the new light . Because such a certain year is shorter than the tropical year , it becomes one
- The lunisolar calendar , a subset of the lunar calendar, re-establishes synchronization with the tropical year by inserting a leap month according to fixed rules.
- Lunistellar calendars - according to the moon and stars
If one of the above calendars has not yet been implemented in any society or religion, one speaks of calendar drafts .
See also: List of calendars (Wikipedia)
Basis of the calendar system: calculation or observation
The basis of all astronomical calendars is the observation of the heavenly bodies. Arithmetic calendars , on the other hand, are based purely on calculations. The best known is the Gregorian calendar with its arithmetic, cyclic leap day arrangements.
Within a calendar system, the basis of the system can change from observation to calculation. Examples are the Jewish calendar and Zoroastrian forms of the Iranian calendar. The background to such a change was the loss of the authorities who had to declare the astronomical observations to be binding (in the case of the Zoroastrians the fall of the Sasanid Empire), or in the case of the Jews, the functionality of these authorities was endangered.
If leap day regulations are included in the conversion formulas for data from different calendar systems (e.g. when converting between dates from the Islamic calendar and the Gregorian calendar), these are approximate formulas, the result of which is occasionally one day off the "real" (historical) date.
Link to a specific era
A calendar system is usually associated with a certain era (→ epoch ), after which the year is counted or named. However, both calendar and era must be separated. Some Asian calendar systems, such as B. the Japanese calendar , have their traditional calendar calculation in the 19th and 20th centuries. Century abandoned and - with regard to the beginning of the year, month division and leap year calculation - adopted the Gregorian calendar, but its traditional year counting (after the rule of the Tenno in Japan, "since the establishment of the Republic of China in 1912" in Taiwan etc.) is retained. Conversely, the Julian calendar was next to the Christian era also with the Byzantine era (counting the years since the creation of the world), the Diocletian era , the Varronian era (since the foundation of the city of Rome), the year designation after the Roman consuls, the Seleucid era and used in the Rumi calendar with the Islamic era.
The proleptic use of epochs and calendars, i.e. their application to dates before their reference date (date of origin), is uncommon with the exception of the Christian era. Dates before the birth of Christ are made according to the Gregorian or Julian calendar, dates between the Julian calendar reform 45 BC. BC and the Gregorian reform, which came into force on October 15, 1582 in Rome and several Catholic territories, are determined according to the Julian calendar.
Common and historical calendar systems
A reliable division into common and historical calendar systems is difficult, as some calendars that have hardly been used for centuries are still used by small groups (e.g. the Julian calendar ) and originally forgotten calendars have found new followers after their rediscovery (e.g. . Mayan calendar and Irish Calendar ).
- So far there is no evidence for the existence of “nature calendars”. They are based on regular natural events. In the case of annual events such as the flood of the Nile , "natural calendars" would be, more precisely, solar calendars, since annual natural events coincide with the seasons and are thus also based on the sun.
- Ancient Roman calendar up to approx. 450 BC - then replaced by a lunisolar calendar
- Islamic calendar
- Sidereal lunar calendar
- Church Calendar : Liturgical Calendar (Roman Catholic)
- Ethiopian Calendar - common in Ethiopia
- Gregorian calendar - the most widely used calendar in the world
- Greek Orthodox calendar (also: Milanković calendar, New Julian calendar, revised Julian calendar) - used only by the so-called New Calendars
- Julian calendar - only some Orthodox churches (in the Altkalendariern ) and in the historical sciences in use
- Coptic calendar (also: Alexandrian calendar) - in the Coptic Orthodox Church in use
- Swedish calendar - used temporarily in Sweden
- Calendar systems based on Christian calendars
- Berber calendar - in use throughout North Africa (a continuation of the Julian calendar)
- Chuch'e calendar - common in North Korea
- Rumi calendar - solar calendar with Hijra counting
- Modern Japanese calendar (also: Gengō calendar) - commonly used in Japan
- Soviet revolution calendar
- Suriyakati calendar - common in Thailand
- Minguo calendar - common in the Republic of China (Taiwan)
- Badi calendar (also: Baha'i calendar) - common among the followers of the Baha'i religion
- Bengali solar calendar - partly in use in Bangladesh and India
- Discordian calendar
- French revolutionary calendar
- Georgian calendar
- Hindu solar calendar
- Indian national calendar (also: Saka calendar) - partly in use in India
- Iranian calendar (also: Jalāli calendar) - used in Iran and Afghanistan
- Irish calendar - back in use in esoteric circles
- Old Icelandic calendar - no longer in use
- Malayalam calendar - partly in use in India
- Maliye calendar - a financial calendar used in the Ottoman Empire, the year counting of which was adapted to the Islamic lunar calendar
- Megalithic calendar based on a theory by Alexander Thom
- Nakaiiy calendar - partly in use in the Maldives
- Orissa Calendar - partially in use in India
- Porhalaan calendar (also: Batak calendar) - partly in use on Sumatra
- Sikh calendar (also: Nanakschahi calendar) - partly used in the religion of the Sikhs
- Tamil calendar
- Turkish calendar - was used before Islam entered Turkish culture
- Zoroastrian calendar: Fasli calendar (also: Parsi calendar) - the Parsi religion in use
Change year calendar
These calendars have a fixed, constant year length of mostly 365 days. They are based on the solar year with 365 1 ⁄ 4 days, but are not solar calendars because they do not have any activation (intercalation, leap year regulation ). Over the years, the calendar year shifts to the solar year. The result are so-called change years.
- Egyptian calendar: administrative calendar - 365-day cycle, until the introduction of a leap year rule in 238 BC. Chr.
- Armenian calendar - 365 day cycle
- Aztec calendar: xihuitl cycle - 365-day cycle, overlaps with a 260-day tōnalpōhualli cycle
- Maya calendar : Haab cycle - 365-day cycle, partially in use again in Mexico and Guatemala, overlaps with the 260-day Tzolkin cycle
- Zoroastrian calendar: Qadimi- and Shenshai calendar (also: Parsi calendar) - 365-day cycle, in the Parsi religion in use
A lunisolar calendar is the combination of a lunar and a solar calendar.
- Babylonian lunar calendar
- Burmese calendar
- Chantarakati calendar - used for Buddhist festivals in Thailand
- Dai Calendar - used by the Dai (people) to determine traditional festivals
- Germanic calendar (also: rune calendar)
- Greek calendar - different lunisolar calendars of the different poles of ancient Greece
- Hindu lunisolar calendar
- Japanese lunisolar calendar - replaced by solar calendar in 1872
- Jewish calendar - used in Jewish societies
- Coligny calendar - a Celtic calendar
- Khmer calendar
- Korean calendar
- Mongolian calendar
- Vikram Sambat - common in Nepal
- Roman calendar from approx. 450 BC. With the introduction of the law of twelve tables
- Saka calendar (also: Shaka-, Caka- or Sasih calendar) - a Hindu calendar with variants in India and Indonesia , especially on Java and Bali
- Tibetan calendar
Lunistellar and other combined calendars
- Egyptian calendar: civil lunar calendar - combination of natural and lunar calendar
- Egyptian lunar calendar: Sothis calendar - Lunistellar calendar
- Old Russian calendar
- Assyrian calendar - like the Babylonian calendar
- Babylonian calendar - originally based on calendar stars, later replaced by the lunisolar calendar
- Chinese calendar - Combination of solar and lunisolar calendar, used in China to determine traditional festivals
- Inca calendar
- Loango Calendar - a calendar based on lunar and Sirius cycles among the Central African Loango people
Calendar without astronomical reference
- Mayan calendar : Tzolkin cycle - 260-day year
- Pawukon calendar (also: Wuku calendar) - 210-day year, common in Bali
Calendar systems that could not previously be assigned
Modern calendar designs
- Almanach des Honnêtes Gens (also: Maréchal calendar)
- Darian Calendar - a 24-month calendar for counting days and years on Mars
- Discordian calendar
- French revolutionary calendar
- Holocene Calendar
- International perpetual calendar (also: Eastman plan or Cotsworth plan) - divides the year into 13 months of 28 days each
- Madler calendar
- Positivist calendar (also: Comte calendar)
- Soviet revolutionary calendar - replaces the 7-day week with a 5-day week, later a 6-day week
- World calendar - divides the year into 4 quarters of 91 days each (31.30,30 days per month)
- Weekly calendar
- Calendar wiki that also includes modern designs by hobbyists
- Joachim Friedrich Quack: Between the sun and the moon - time calculation in ancient Egypt , original publication in: H. Falk (ed.), From the ruler to the dynasty. On the nature of continuous calculation of time in antiquity and the present , Bremen 2002, p. 38, pdf.