Time intervals specify an amount of time. They may be specified in four ways: Start and end, such as 2002-03-01T13:00:00Z/2003-05-11T15:30:00Z Start and duration, such as 2002-03-01T13:00:00Z/P1Y2M10DT2H30M Duration and end, such as P1Y2M10DT2H30M/2003-05-11T15:30:00Z Duration only, such as P1Y2M10DT2H30M Of these, the first three require two separate values, separated by the interval designator, which is usually a forward slash "/". (The double h ...

See also:

ISO 8601, ISO 8601 - History of the standard, ISO 8601 - General principles, ISO 8601 - Dates, ISO 8601 - Calendar date, ISO 8601 - Week dates, ISO 8601 - Ordinal dates, ISO 8601 - Further details about dates, ISO 8601 - Times, ISO 8601 - Time zones, ISO 8601 - Combined representations, ISO 8601 - Duration, ISO 8601 - Time interval, ISO 8601 - Repeating intervals, ISO 8601 - Usage

Read more here: » ISO 8601: Encyclopedia II - ISO 8601 - Time interval

The Julian day number can be calculated using the following formulas: All divisions (except for JD) are integer divisions, meaning the remainder in the division is discarded. The months January to December are 1 to 12. Astronomical year numbering is used, thus 1 BC is 0, 2 BC is −1, and 4713 BC is −4712. For a date in the Gregorian calendar (at noon): For a date in the Julian calendar (at noon): For the full Julian Date, not counting leap seconds (divisions are real numbers): So, for example, 1 January 20 ...

See also:

Julian day, Julian day - Julian Date, Julian day - Alternatives, Julian day - History, Julian day - Calculation, Julian day - Other Usages, Julian day - Footnotes

Read more here: » Julian day: Encyclopedia II - Julian day - Calculation

Year zero - South Asian moon calendars. All eras used with Hindu and Buddhist calendars, such as the Saka era or the Kali Yuga, begin with a year 0 because all of these calendars use elapsed, expired, or complete years, in contrast with most other calendars which use current years. A complete year had not yet elapsed for any date in the year beginning at the epoch, thus that could not be year 1 — instead, it was year 0. This is similar to the Western method of stating a person's age — people do not reach age ...

See also:

Year zero, Year zero - Historians, Year zero - Astronomers, Year zero - Other year zero traditions, Year zero - South Asian moon calendars, Year zero - Mesoamerican Maya historians, Year zero - Third millennium, Year zero - Media, Year zero - Notes

Read more here: » Year zero: Encyclopedia II - Year zero - Other year zero traditions

The Julian Date (JD) is the Julian day number plus the decimal fraction of the day that has elapsed since noon. Historical Julian Dates were recorded relative to GMT or Ephemeris Time, but the International Astronomical Union now recommends that Julian Dates be specified in Terrestrial Time, and that when necessary to specify Julian Dates using a different time scale, that the time scale used be indicated when required, such as JD(UT1). The fraction of the day is found by converting the number of hours, minutes, and seconds after ...

See also:

Julian day, Julian day - Julian Date, Julian day - Alternatives, Julian day - History, Julian day - Calculation, Julian day - Other Usages, Julian day - Footnotes

Read more here: » Julian day: Encyclopedia II - Julian day - Julian Date

He was the subject of a 64-chapter (in eight volumes) The Novel of the Prince of Qin of the Great Tang (大唐秦王詞話 Datang Qin Wang Cihua) by Zhu Shenglin (諸聖鄰) of the Ming Dynasty. The novel is also known as The Biography of the Prince of Qin of the Tang Dynasty (唐秦王本傳 Tang Qin Wang Benzhuan), Romance of Tang (唐傳演義 Tang Chuan Yiyan), and Romance of the Prince o ...

See also:

Emperor Taizong of Tang, Emperor Taizong of Tang - Early Achievements, Emperor Taizong of Tang - The Palace Coup at the Xuanwu Gate, Emperor Taizong of Tang - Family, Emperor Taizong of Tang - Literature, Emperor Taizong of Tang - Chinese popculture

Read more here: » Emperor Taizong of Tang: Encyclopedia II - Emperor Taizong of Tang - Literature

He had: Wende-shunsheng Empress (文德順聖皇后), Zhangsun-shi (長孫氏) Xian Consort (賢妃), Xu Hui (徐惠) Consort Yang I (楊妃) Consort Yang II (楊妃) Yang-shi (楊氏) Consort Yin (陰妃) Consort Yan (燕妃) Secondary Consort Wei (韋貴妃) Wang-shi (王氏) He had fourteen sons (in order): Crown Prince Li Chengqian: son of Wende Empress Prince Chu, Li Kuan (楚王寬): son of one from the harem　　See also:

Emperor Taizong of Tang, Emperor Taizong of Tang - Early Achievements, Emperor Taizong of Tang - The Palace Coup at the Xuanwu Gate, Emperor Taizong of Tang - Family, Emperor Taizong of Tang - Literature, Emperor Taizong of Tang - Chinese popculture

Read more here: » Emperor Taizong of Tang: Encyclopedia II - Emperor Taizong of Tang - Family

In the movie Back to the Future Dr. Emmett Brown, the inventor of a time machine, enters the input date of the "birth of Christ" on a keypad as December 25, 0000. Not only does the entered input date use the astronomical year number, but the entered input date implies that Jesus was actually born in that year (he was born between 8 BC and AD 9, according to different sources), and also that Christianity's celebration of Christmas on December 25 is a true historical anniversary rather than a traditional date (biblical clues indi ...

See also:

Year zero, Year zero - Historians, Year zero - Astronomers, Year zero - Other year zero traditions, Year zero - South Asian moon calendars, Year zero - Mesoamerican Maya historians, Year zero - Third millennium, Year zero - Media, Year zero - Notes

Read more here: » Year zero: Encyclopedia II - Year zero - Media

Taizong was born in Lunghsi (in present-day Kansu. Taizong was known as a Hojen (胡人).) as the second son of Li Yuan, and was of one-quarter Xianbei (a people related to modern-day Turks) blood. The most capable and militarily inclined of Li Yuan's many sons, Taizong showed his promise at an early age, helping to rescue Emperor Yang from a Turkic ambush and besiegement at the age of sixteen. In 616, the eighteen-year-old Taizong followed his general-father to his garrison-post at Jinyang, Shanxi, where he instigated his father to stage a ...

See also:

Emperor Taizong of Tang, Emperor Taizong of Tang - Early Achievements, Emperor Taizong of Tang - The Palace Coup at the Xuanwu Gate, Emperor Taizong of Tang - Family, Emperor Taizong of Tang - Literature, Emperor Taizong of Tang - Chinese popculture

Read more here: » Emperor Taizong of Tang: Encyclopedia II - Emperor Taizong of Tang - Early Achievements

Historians note that the 3rd millennium began on 1 January 2001 because they regard the Christian Era as beginning with year 1, whereas many people assumed that it began on 1 January 2000 because that was when the most significant digit of the year changed (1 → 2). So many people confound the "end of the years nineteen hundreds" and the "end of the 20th century", which certainly occured 366 days later. Astronomical year numbering cannot be used to support year 2000 as the first year of the 3rd millennium because of uncertainty regar ...

See also:

Year zero, Year zero - Historians, Year zero - Astronomers, Year zero - Other year zero traditions, Year zero - South Asian moon calendars, Year zero - Mesoamerican Maya historians, Year zero - Third millennium, Year zero - Media, Year zero - Notes

Read more here: » Year zero: Encyclopedia II - Year zero - Third millennium

Astronomers include a year 0 immediately before year 1. The first use of an astronomical year 0 is traditionally attributed to Jacques Cassini in his Tables astronomiques (Astronomical Tables, 1740). His stated reasons for including a year zero were (page 5, translated from French): The year 0 is that in which one supposes that Jesus Christ was born, which several chronologists mark 1 before the birth of Jesus Christ and which we marked 0, so that the sum of the years before and after Jesus Christ gives the interval which is between these years, and where numbers divisible by 4 mark the leap years ...

See also:

Year zero, Year zero - Historians, Year zero - Astronomers, Year zero - Other year zero traditions, Year zero - South Asian moon calendars, Year zero - Mesoamerican Maya historians, Year zero - Third millennium, Year zero - Media, Year zero - Notes

Read more here: » Year zero: Encyclopedia II - Year zero - Astronomers

Hindu mythology speaks of four eras or ages, of which we are currently in the last. The four are: Krita Yuga or Satya Yuga Tretā Yuga Dvāpara Yuga Kali Yuga They are often translated into English as the golden, silver, bronze and iron ages. (Yuga means era or age.) It is believed that the ages see a gradual decline of dharma, wisdom, knowledge, intellectual capability, life span and emotional and physical strength. The epoch provided above is the start of the Kali Yuga. The Ka ...

See also:

Hindu calendar, Hindu calendar - Basic structure, Hindu calendar - Day, Hindu calendar - Tithi, Hindu calendar - Vaasara, Hindu calendar - Nakshatra, Hindu calendar - Yoga, Hindu calendar - Karana, Hindu calendar - Month and year of the solar calendar, Hindu calendar - Months of the lunisolar calendar, Hindu calendar - Naming lunar months, Hindu calendar - Religious observances in case of extra and lost months, Hindu calendar - Year of the lunisolar calendar, Hindu calendar - Another kind of lunisolar calendar, Hindu calendar - Correspondence of the lunisolar calendar to the solar calendar, Hindu calendar - Year numbering, Hindu calendar - Year names, Hindu calendar - Eras, Hindu calendar - History

Read more here: » Hindu calendar: Encyclopedia II - Hindu calendar - Eras

Another important calendar for the Maya was the Venus cycle. The Maya were excellent astronomers, and could calculate the Venus cycle extremely accurately. There are six pages in the Dresden Codex (one of the Maya codices) devoted to the accurate calculation of the location of Venus. The Maya were able to achieve such accuracy by careful observation over many years. The Venus cycle was especially important because the Maya believed it was associated with war and used it to divine good times for coronations and war. Maya rulers planned for wars to begin when Venus rose. The Maya also possibly tracked other planets’ movements, i ...

See also:

Maya calendar, Maya calendar - General overview, Maya calendar - Maya concepts of time, Maya calendar - Tzolk'in, Maya calendar - Divination, Maya calendar - Origin of the Tzolkin, Maya calendar - Haab, Maya calendar - Wayeb, Maya calendar - Calendar Round, Maya calendar - Long Count, Maya calendar - Calculating Long Count dates, Maya calendar - Calculating the Tzolkin date portion, Maya calendar - Calculating the Haab date portion, Maya calendar - End of the world?, Maya calendar - Venus cycle

Read more here: » Maya calendar: Encyclopedia II - Maya calendar - Venus cycle

Now that the days are defined, we shall speak of how the solar calendar reckons its months and year. As has been previously noted, the sun is observed to travel along the ecliptic. The ecliptic is now divided into twelve parts called rāshi-s, starting from the point of Meshādi defined above and moving eastwards. They are: Mesha Vrishabha Mithuna Kataka Simha Kanyā Tulā Vrishchika Dhanus Makara Kumbha Mīna ...

See also:

Hindu calendar, Hindu calendar - Basic structure, Hindu calendar - Day, Hindu calendar - Tithi, Hindu calendar - Vaasara, Hindu calendar - Nakshatra, Hindu calendar - Yoga, Hindu calendar - Karana, Hindu calendar - Month and year of the solar calendar, Hindu calendar - Months of the lunisolar calendar, Hindu calendar - Naming lunar months, Hindu calendar - Religious observances in case of extra and lost months, Hindu calendar - Year of the lunisolar calendar, Hindu calendar - Another kind of lunisolar calendar, Hindu calendar - Correspondence of the lunisolar calendar to the solar calendar, Hindu calendar - Year numbering, Hindu calendar - Year names, Hindu calendar - Eras, Hindu calendar - History

Read more here: » Hindu calendar: Encyclopedia II - Hindu calendar - Month and year of the solar calendar

When a new moon occurs before sunrise on a day, that day is said to be the first day of the lunar month. So it is evident that the end of the lunar month will coincide with a new moon. A lunar month has 29 or 30 days (according to the movement of the moon). The tithi at sunrise of a day is the only label of the day. There is no running day number from the first day to the last day of the month. This has some unique results, as explained below: Sometimes two successive days have the same tithi. In such a case, the ...

See also:

Hindu calendar, Hindu calendar - Basic structure, Hindu calendar - Day, Hindu calendar - Tithi, Hindu calendar - Vaasara, Hindu calendar - Nakshatra, Hindu calendar - Yoga, Hindu calendar - Karana, Hindu calendar - Month and year of the solar calendar, Hindu calendar - Months of the lunisolar calendar, Hindu calendar - Naming lunar months, Hindu calendar - Religious observances in case of extra and lost months, Hindu calendar - Year of the lunisolar calendar, Hindu calendar - Another kind of lunisolar calendar, Hindu calendar - Correspondence of the lunisolar calendar to the solar calendar, Hindu calendar - Year numbering, Hindu calendar - Year names, Hindu calendar - Eras, Hindu calendar - History

Read more here: » Hindu calendar: Encyclopedia II - Hindu calendar - Months of the lunisolar calendar

There is another kind of lunisolar calendar which differs from the former in the way the months are named. This section describes the differences involved, and may be skipped if the article is already too complicated for the reader. It is only included for completeness. When a full moon (instead of new moon) occurs before sunrise on a day, that day is said to be the first day of the lunar month. In this case, the end of the lunar month will coincide with a full moon. This is called the pūrnimānta māna or "full-moon-ending reckoning", as against ...

See also:

Hindu calendar, Hindu calendar - Basic structure, Hindu calendar - Day, Hindu calendar - Tithi, Hindu calendar - Vaasara, Hindu calendar - Nakshatra, Hindu calendar - Yoga, Hindu calendar - Karana, Hindu calendar - Month and year of the solar calendar, Hindu calendar - Months of the lunisolar calendar, Hindu calendar - Naming lunar months, Hindu calendar - Religious observances in case of extra and lost months, Hindu calendar - Year of the lunisolar calendar, Hindu calendar - Another kind of lunisolar calendar, Hindu calendar - Correspondence of the lunisolar calendar to the solar calendar, Hindu calendar - Year numbering, Hindu calendar - Year names, Hindu calendar - Eras, Hindu calendar - History

Read more here: » Hindu calendar: Encyclopedia II - Hindu calendar - Another kind of lunisolar calendar

Neither the Tzolkin nor the Haab system numbered the years. The combination of a Tzolkin date and a Haab date was enough to identify a date to most people's satisfaction, as such a combination didn't occur again for another 52 years, well above life expectancy. Because the two calendars were based on 260 days and 365 days respectively, the whole cycle would repeat itself every 52 Haab years exactly. This period was known as a Calendar Round. The end of the Calendar Round was a period of unrest and bad luck among the Maya, as they waited in expectation to see if the ...

See also:

Maya calendar, Maya calendar - General overview, Maya calendar - Maya concepts of time, Maya calendar - Tzolk'in, Maya calendar - Divination, Maya calendar - Origin of the Tzolkin, Maya calendar - Haab, Maya calendar - Wayeb, Maya calendar - Calendar Round, Maya calendar - Long Count, Maya calendar - Calculating Long Count dates, Maya calendar - Calculating the Tzolkin date portion, Maya calendar - Calculating the Haab date portion, Maya calendar - End of the world?, Maya calendar - Venus cycle

Read more here: » Maya calendar: Encyclopedia II - Maya calendar - Calendar Round

The Haab was the Maya solar calendar made up of eighteen months of twenty days each and a five day month at the end of the year known as Wayeb or Uayeb that was called "the nameless days." Victoria Bricker estimates that the Haab was first used around 550 BC with the starting point of the winter solstice. The Haab was the foundation of the agrarian calendar and the month names are based on the seasons and agricultural events. For example the thirteenth month, Mac, may refer to the end of the rainy season and the fourteenth month, Kankin ...

See also:

Maya calendar, Maya calendar - General overview, Maya calendar - Maya concepts of time, Maya calendar - Tzolk'in, Maya calendar - Divination, Maya calendar - Origin of the Tzolkin, Maya calendar - Haab, Maya calendar - Wayeb, Maya calendar - Calendar Round, Maya calendar - Long Count, Maya calendar - Calculating Long Count dates, Maya calendar - Calculating the Tzolkin date portion, Maya calendar - Calculating the Haab date portion, Maya calendar - End of the world?, Maya calendar - Venus cycle

Read more here: » Maya calendar: Encyclopedia II - Maya calendar - Haab

The most important of these calendars is one with a period of 260 days. This 260-day calendar was prevalent across all Mesoamerican societies, and is of great antiquity (almost certainly the oldest of the calendars). It is still used in some regions of Oaxaca, and amongst the Maya communities of the Guatemalan highlands. The Maya version is commonly known to scholars as the Tzolkin, or Tzolk'in in the revised orthography of the Academia de Lenguas Mayas de Guatemala. The Tzolkin combined with another 365-day calendar (known as ...

See also:

Maya calendar, Maya calendar - General overview, Maya calendar - Maya concepts of time, Maya calendar - Tzolk'in, Maya calendar - Divination, Maya calendar - Origin of the Tzolkin, Maya calendar - Haab, Maya calendar - Wayeb, Maya calendar - Calendar Round, Maya calendar - Long Count, Maya calendar - Calculating Long Count dates, Maya calendar - Calculating the Tzolkin date portion, Maya calendar - Calculating the Haab date portion, Maya calendar - End of the world?, Maya calendar - Venus cycle

Read more here: » Maya calendar: Encyclopedia II - Maya calendar - General overview

With the development of the place-notational Long Count calendar (believed to have been inherited from other Mesoamerican cultures), the Maya had an elegant system within which events could be recorded in a linear relationship to one another, and also with respect to the calendar ("linear time") itself. In theory, this system could readily be extended to delineate any length of time desired, by simply adding to the number of higher-order place markers used (and thereby generating an ever-increasing sequence of day-multiples, each day in the ...

See also:

Maya calendar, Maya calendar - General overview, Maya calendar - Maya concepts of time, Maya calendar - Tzolk'in, Maya calendar - Divination, Maya calendar - Origin of the Tzolkin, Maya calendar - Haab, Maya calendar - Wayeb, Maya calendar - Calendar Round, Maya calendar - Long Count, Maya calendar - Calculating Long Count dates, Maya calendar - Calculating the Tzolkin date portion, Maya calendar - Calculating the Haab date portion, Maya calendar - End of the world?, Maya calendar - Venus cycle

Read more here: » Maya calendar: Encyclopedia II - Maya calendar - Maya concepts of time

Mayanists have bestowed the name tzolkin (or tzolk'in, in the revised orthography which is now preferred) on the Maya version of the Mesoamerican 260-day calendar. The word was coined based on the Yucatec language, with an intended meaning of "count of days". The actual names of this calendar as used by the pre-Columbian Maya are not known. The Aztec calendar equivalent was called by them t ...

See also:

Maya calendar, Maya calendar - General overview, Maya calendar - Maya concepts of time, Maya calendar - Tzolk'in, Maya calendar - Divination, Maya calendar - Origin of the Tzolkin, Maya calendar - Haab, Maya calendar - Wayeb, Maya calendar - Calendar Round, Maya calendar - Long Count, Maya calendar - Calculating Long Count dates, Maya calendar - Calculating the Tzolkin date portion, Maya calendar - Calculating the Haab date portion, Maya calendar - End of the world?, Maya calendar - Venus cycle

Read more here: » Maya calendar: Encyclopedia II - Maya calendar - Tzolk'in

A lunisolar calendar is always a calendar based on the moon's celestial motion, which in a way keeps itself close to a solar calendar based on the sun's (apparent) celestial motion. That is, the lunisolar calendar's new year is to kept always close (within certain limits) to a solar calendar's new year. Since the Hindu lunar month names are based on solar transits, and the month of Chaitra will, as defined above, always be close to the solar month of See also:

Hindu calendar, Hindu calendar - Basic structure, Hindu calendar - Day, Hindu calendar - Tithi, Hindu calendar - Vaasara, Hindu calendar - Nakshatra, Hindu calendar - Yoga, Hindu calendar - Karana, Hindu calendar - Month and year of the solar calendar, Hindu calendar - Months of the lunisolar calendar, Hindu calendar - Naming lunar months, Hindu calendar - Religious observances in case of extra and lost months, Hindu calendar - Year of the lunisolar calendar, Hindu calendar - Another kind of lunisolar calendar, Hindu calendar - Correspondence of the lunisolar calendar to the solar calendar, Hindu calendar - Year numbering, Hindu calendar - Year names, Hindu calendar - Eras, Hindu calendar - History

Read more here: » Hindu calendar: Encyclopedia II - Hindu calendar - Correspondence of the lunisolar calendar to the solar calendar

The Hindu Calendar descends from the Vedic times. There are many references to calendrics in the Vedas. The Vedānga (adjunct to Veda) called Jyautisha (literally, "celestial body study") prescribed all the aspects of the Hindu calendars. After the Vedic period, there were many scholars such as Āryabhata (5th century), Varāhamihira (6th century) and Bhāskara (12th century) who were experts in Jyautisha and contributed to the development of the Hindu Calendar. The most widely used authoritative text for the Hindu Calendars in the Sūrya Siddhānta, a text of uncertain ...

See also:

Hindu calendar, Hindu calendar - Basic structure, Hindu calendar - Day, Hindu calendar - Tithi, Hindu calendar - Vaasara, Hindu calendar - Nakshatra, Hindu calendar - Yoga, Hindu calendar - Karana, Hindu calendar - Month and year of the solar calendar, Hindu calendar - Months of the lunisolar calendar, Hindu calendar - Naming lunar months, Hindu calendar - Religious observances in case of extra and lost months, Hindu calendar - Year of the lunisolar calendar, Hindu calendar - Another kind of lunisolar calendar, Hindu calendar - Correspondence of the lunisolar calendar to the solar calendar, Hindu calendar - Year numbering, Hindu calendar - Year names, Hindu calendar - Eras, Hindu calendar - History

Read more here: » Hindu calendar: Encyclopedia II - Hindu calendar - History