Balinese saka calendar
The Balinese saka calendar is one of two calendars used on the Indonesian island of Bali. Unlike the 210-day pawukon calendar, it is based on the phases of the Moon, is the same length as the Gregorian year. Based on a lunar calendar, the saka year comprises sasih, of 30 days each. However, because the lunar cycle is shorter than 30 days, the lunar year has a length of 354 or 355 days, the calendar is adjusted to prevent it losing synchronization with the lunar or solar cycles; the months are adjusted by allocating two lunar days to one solar day every 9 weeks. This day is called ngunalatri, Sanskrit for "minus one night". To stop the Saka from lagging behind the Gregorian calendar – as happens with the Islamic calendar, an extra month, known as an intercalary month, is added after the 11th month, or after the 12th month; the length of these months is calculated according to the normal 63-day cycle. An intercalary month is added whenever necessary to prevent the final day of the 7th month, known as Tilem Kapitu, from falling in the Gregorian month of December.
The names the twelve months are taken from a mixture of Old Balinese and Sanskrit words for 1 to 12, are as follows: Kasa Karo Katiga Kapat Kalima Kanem Kapitu Kawalu Kasanga Kadasa Jyestha SadhaEach month begins the day after a new moon and has 15 days of waxing moon until the full moon 15 days of waning, ending on the new moon. Both sets of days are numbered 1 to 15; the first day of the year is the day after the first new moon in March. Note, that Nyepi falls on the first day of Kadasa, that the years of the Saka era are counted from that date; the calendar is 78 years behind the Gregorian calendar, is calculated from the beginning of the Saka Era in India. It is used alongside the 210-day Balinese pawukon calendar, Balinese festivals can be calculated according to either year; the Indian saka calendar was used for royal decrees as early as the ninth century CE. The same calendar was used in Java until Sultan Agung replaced it with the Javanese calendar in 1633; the Balinese Hindu festival of Nyepi, the day of silence, marks the start of the Saka year.
Tilem Kepitu, the last day of the 7th month, is known as Siva Ratri, is a night dedicated to the god Shiva. Devotees stay up all meditate. There are another 24 ceremonial days in the Saka year celebrated at Purnama. Eiseman, Fred B. Jr, Bali: Sekalia and Niskala Volume I: Essays on Religion and Art pp 182–185, Periplus Editions, 1989 ISBN 0-945971-03-6 Haer, Debbie Guthrie. ISBN 981 3018 496 Hobart, Angela. ISBN 0 631 17687 X Ricklefs, M. C.
The Ethiopian calendar or Eritrean calendar is the principal calendar used in Ethiopia and serves as the liturgical year for Christians in Eritrea and Ethiopia belonging to the Eritrean Orthodox Tewahedo Church, Ethiopian Orthodox Tewahedo Church, Eastern Catholic Churches, the Coptic Orthodox Church of Alexandria, Ethiopian-Eritrean Evangelicalism. It is a solar calendar which in turn derives from the Egyptian calendar, but like the Julian calendar, it adds a leap day every four years without exception, begins the year on August 29 or August 30 in the Julian calendar. A gap of 7–8 years between the Ethiopian and Gregorian calendars results from an alternative calculation in determining the date of the Annunciation. Like the Coptic calendar, the Ethiopic calendar has 12 months of 30 days plus 5 or 6 epagomenal days, which comprise a thirteenth month; the Ethiopian months begin on the same days as those of the Coptic calendar, but their names are in Ge'ez. A 6th epagomenal day is added every 4 years, without exception, on August 29 of the Julian calendar, 6 months before the corresponding Julian leap day.
Thus the first day of the Ethiopian year, 1 Mäskäräm, for years between 1900 and 2099, is September 11. However, it falls on September 12 in years before the Gregorian leap year. Enkutatash is the word for the Ethiopian New Year in Amharic, the official language of Ethiopia, while it is called Ri'se Awde Amet in Ge'ez, the term preferred by the Ethiopian & Eritrean Orthodox Tewahedo Churchs, it occurs on September 11th in the Gregorian Calendar. The Ethiopian Calendar Year 1998 Amätä Məhrät began on the Gregorian Calendar Year on September 11th, 2005. However, the Ethiopian Years 1992 and 1996 began on the Gregorian Dates of'September 12th 1999' and'2003' respectively; this date correspondence applies for the Gregorian years 1900 to 2099. The Ethiopian leap year is every four without exception, while Gregorian centurial years are only leap years when divisible by 400; as the Gregorian year 2000 is a leap year, the current correspondence lasts two centuries instead. The start of the Ethiopian year falls on August 30th.
This date corresponds to the Old-Style Julian Calendar. This deviation between the Julian and the Gregorian Calendar will increase with the passing of the time. You can observe the real start date in the future centuries in a Gregorian to Ethiopian Date Converter. To indicate the year and followers of the Eritrean churches today use the Incarnation Era, which dates from the Annunciation or Incarnation of Jesus on March 25, AD 9, as calculated by Annianus of Alexandria c. 400. Meanwhile, Europeans adopted the calculations made by Dionysius Exiguus in AD 525 instead, which placed the Annunciation 8 years earlier than had Annianus; this causes the Ethiopian year number to be 8 years less than the Gregorian year number from January 1 until September 10 or 11 7 years less for the remainder of the Gregorian year. In the past, a number of other eras for numbering years were widely used in Ethiopia and the Kingdom of Aksum; the most important era – once used by the Eastern Christianity, still used by the Coptic Orthodox Church of Alexandria – was the Era of Martyrs known as the Diocletian Era, or the era of Diocletian and the Martyrs, whose first year began on August 29, 284.
Respective to the Gregorian and Julian New Year's Days, 31⁄2 to 4 months the difference between the Era of Martyrs and the Anni Domini is 285 years. This is because in AD 525, Dionysius Exiguus decided to add 15 Metonic cycles to the existing 13 Metonic cycles of the Diocletian Era to obtain an entire 532 year medieval Easter cycle, whose first cycle ended with the year Era of Martyrs 247 equal to year DXXXI, it is because 532 is the product of the Metonic cycle of 19 years and the solar cycle of 28 years. Around AD 400, an Alexandrine monk called Panodoros fixed the Alexandrian Era, the date of creation, on 29 August 5493 BC. After the 6th century AD, the era was used by Ethiopian chronologists; the twelfth 532 year-cycle of this era began on 29 August AD 360, so 4×19 years after the Era of Martyrs. Bishop Anianos preferred the Annunciation style as 25 March, thus he shifted the Panodoros era by about six months, to begin on 25 March 5492 BC. In the Ethiopian calendar this was equivalent to 15 Magabit 5501 B.
C.. The Anno Mundi era remained in usage until the late 19th century; the 4 year leap-year cycle is associated with the four Evangelists: the first year after an Ethiopian leap year is named the John-year, followed by the Matthew-year, the Mark-year. The year with the 6th epagomenal day is traditionally designated as the Luke-year. There are no exceptions to the 4 year leap-year cycle, like the Julian calendar but unlike the Gregorian calendar; these dates are valid only from March 1900 to February 2100. This is because 1900 and 2100 are not leap years in the Gregorian calendar, while they are still leap year
Arch of Constantine
The Arch of Constantine is a triumphal arch in Rome, situated between the Colosseum and the Palatine Hill. It was erected by the Roman Senate to commemorate Constantine I's victory over Maxentius at the Battle of Milvian Bridge in 312. Dedicated in 315, it is the largest Roman triumphal arch; the arch spans the Via triumphalis, the way taken by the emperors when they entered the city in triumph. Though dedicated to Constantine, much of the decorative material incorporated earlier work from the time of the emperors Trajan and Marcus Aurelius, is thus a collage; the last of the existing triumphal arches in Rome, it is the only one to make extensive use of spolia, reusing several major reliefs from 2nd century imperial monuments, which give a striking and famous stylistic contrast to the sculpture newly created for the arch. This earned it the derisive nickname of Cornacchia di Esopo Aesop's Crow; the arch is 25.9 m wide and 7.4 m deep. It has three archways, the central one being 11.5 m high and 6.5 m wide and the lateral archways 7.4 m by 3.4 m each.
Above the archways is placed the attic, composed of brickwork revetted with marble. A staircase within the arch is entered from a door at some height from the ground, on the west side, facing the Palatine Hill; the general design with a main part structured by detached columns and an attic with the main inscription above is modelled after the example of the Arch of Septimius Severus on the Roman Forum. The arch, constructed between 312 and 315 AD, was dedicated by the Senate to commemorate ten years of Constantine's reign and his victory over the reigning emperor Maxentius at the Battle of Milvian Bridge on 28 October 312, as described on its attic inscription, opened on 25 July 315. Not only did the Roman senate give the arch for Constantine's victory, they were celebrating decennia, a series of games that happens every decade for the Romans. On this occasion they said many prayers. However, Constantine had entered Rome on 29 October 312, amidst great rejoicing, the Senate commissioned the monument.
Constantine left Rome within two months and did not return till 326. The location, between the Palatine Hill and the Caelian Hill, spanned the ancient route of Roman triumphs at its origin, where it diverged from the Via sacra; this route was that taken by the emperors. This route started at the Campus Martius, led through the Circus Maximus, around the Palatine Hill. During the Middle Ages, the Arch of Constantine was incorporated into one of the family strongholds of ancient Rome, as shown in the painting by Herman van Swanevelt, here. Works of restoration were first carried out in the 18th century, the last excavations have taken place in the late 1990s, just before the Great Jubilee of 2000; the arch served as the finish line for the marathon athletic event for the 1960 Summer Olympics. There has been much controversy over the origins of the arch, with some scholars claiming that it should no longer be referred to as Constantine's arch, but is in fact an earlier work from the time of Hadrian, reworked during Constantine's reign, or at least the lower part.
Another theory holds that it was erected, or at least started, by Maxentius, one scholar believed it was as early as the time of Domitian. Whatever the faults of Maxentius, his reputation in Rome was influenced by his contributions to public building. By the time of his accession in 306 Rome was becoming irrelevant to the governance of the empire, most emperors choosing to live elsewhere and focusing on defending the fragile boundaries, where they founded new cities; this factor contributed to his ability to seize power. By contrast Maxentius concentrated on restoring the capital, his epithet being conservator urbis suae, thus Constantine was perceived amongst other things as the deposer of one of the city's greatest benefactors, needed to acquire legitimacy. Much controversy has surrounded the patronage of the public works of this period; the German philosopher, Walter Benjamin observed that history is seen through the eyes of the victor, Constantine and his biographers were no exception. Issuing a damnatio memoriae.
There remains considerable uncertainty regarding the patronage of early fourth century public buildings, including the Arch of Constantine, which may have been an Arch of Maxentius. Constantine's Arch is an important example cited in surveys of art history, of the stylistic changes of the 4th century, the "collapse of the classical Greek canon of forms during the late Roman period", a sign the city was in decline, would soon be eclipsed by Constantine's founding of a new capital at Constantinople in 324; the contrast between the styles of the re-used Imperial reliefs of Trajan and Marcus Aurelius and those newly made for the arch is dramatic and, according to Ernst Kitzinger, "violent", although it should be noted that where the head of an earlier emperor was replaced by that of Constantine the artist was still able to achieve a "soft, delicate rendering of the face of Constantine", "a far cry from the dominant style of the workshop". It remains the most impressive surviving civic monument from Rome in Late Antiquity, but is one of the most controversial with r
The Byzantine calendar called "Creation Era of Constantinople" or "Era of the World", was the calendar used by the Eastern Orthodox Church from c. 691 to 1728 in the Ecumenical Patriarchate. It was the official calendar of the Byzantine Empire from 988 to 1453, of Kievan Rus' and Russia from c. 988 to 1700. Since "Byzantine" is a historiographical term, the original name uses the noun "Roman" as it was how the Eastern Roman Empire continued calling itself; the calendar was based on the Julian calendar, except that the year started on 1 September and the year number used an Anno Mundi epoch derived from the Septuagint version of the Bible. It placed the date of creation at 5509 years before the Incarnation, was characterized by a certain tendency, a tradition among Jews and early Christians to number the years from the calculated foundation of the world, its Year One, marking the supposed date of creation, was September 1, 5509 BC, to August 31, 5508 BC. It is not known when; the first appearance of the term is in the treatise of a certain "monk and priest", who mentions all the main variants of the "World Era" in his work.
Georgios argues that the main advantage of the World era is the common starting point of the astronomical lunar and solar cycles, of the cycle of indictions, the usual dating system in Byzantium since the 6th century. He already regards it as the most convenient for the Easter computus. Complex calculations of the 19-year lunar and 28-year solar cycles within this world era allowed scholars to discover the cosmic significance of certain historical dates, such as the birth or the crucifixion of Jesus; this date underwent minor revisions before being finalized in the mid-7th century, although its precursors were developed c. AD 412. By the second half of the 7th century, the Creation Era was known in Western Europe, at least in Great Britain. By the late 10th century around AD 988, when the era appears in use on official government records, a unified system was recognized across the Eastern Roman world; the era was calculated as starting on September 1, Jesus was thought to have been born in the year 5509 since the creation of the world.
Historical time was thus calculated from the creation, not from Christ's birth, as in the west after the Anno Domini system was adopted between 6th and 9th centuries. The Eastern Church avoided the use of the Anno Domini system of Dionysius Exiguus, since the date of Christ's birth was debated in Constantinople as late as the 14th century. Otherwise the Byzantine calendar was identical to the Julian Calendar except that: the names of the months were transcribed from Latin into Greek; the leap day of the Byzantine calendar was obtained in an identical manner to the bissextile day of the original Roman version of the Julian calendar, by doubling the sixth day before the calends of March, i.e. by doubling 24 February. The Byzantine World Era was replaced in the Orthodox Church by the Christian Era, utilized by Patriarch Theophanes I Karykes in 1597, afterwards by Patriarch Cyril Lucaris in 1626, formally established by the Church in 1728. Meanwhile, as Russia received Orthodox Christianity from Byzantium, she inherited the Orthodox Calendar based on the Byzantine Era.
After the collapse of the Byzantine Empire in 1453, the era continued to be used by Russia, which witnessed millennialist movements in Moscow in AD 1492. It was only in AD 1700 that the Byzantine World Era in Russia was changed to the Julian Calendar by Peter the Great, it still forms the basis of traditional Orthodox calendars up to today. September AD 2000 began the year 7509 AM; the earliest extant Christian writings on the age of the world according to the Biblical chronology are by Theophilus, the sixth bishop of Antioch from the Apostles, in his apologetic work To Autolycus, by Julius Africanus in his Five Books of Chronology. Both of these early Christian writers, following the Septuagint version of the Old Testament, determined the age of the world to have been about 5,530 years at the birth of Christ. Ben Zion Wacholder points out that the writings of the Church Fathers on this subject are of vital significance, in that through the Christian chronographers a window to the earlier Hellenistic biblical chronographers is preserved: An immense intellectual effort was expended during the Hellenistic period by both Jews and pagans to date creation, the flood, building of the Temple...
In the course of their studies, men such as Tatian of Antioch, Clement of Alexandria, Hippolytus of Rome
Vikram Samvat. It uses solar sidereal years; the Vikram Samvat is notable because many medieval era inscriptions use it. It is said to be named after the legendary king Vikramaditya, but the term "Vikrama Samvat" does not appear in the historical records before the 9th century, rather the same calendaring system is found by other names such as Krita and Malava. In the colonial era scholarship, the era was believed to be based on the commemoration of King Vikramaditya expelling the Sakas from Ujjain; however epigraphical evidence and scholarship suggest that this theory has no historical basis and likely was an error. Starting in the 9th century and thereafter, epigraphical artwork uses Vikrama-Samvat, suggesting that sometime around the 9th-century, the Hindu calendar era, in use became popular as Vikram Samvat, while Buddhist and Jain epigraphy continued to use an era based on the Buddha or the Mahavira. According to popular tradition, the legendary king Vikramaditya of Ujjain established the Vikrama Samvat era after defeating the Śakas.
Kalakacharya Kathanaka by the Jain sage Mahesarasuri gives the following account: Gandharvasena, the then-powerful king of Ujjain, abducted a nun called Sarasvati, the sister of the monk. The enraged monk sought the help of the Śaka ruler King Sahi in Sistan. Despite heavy odds but aided by miracles, the Śaka king defeated Gandharvasena and made him a captive. Sarasvati was repatriated; the defeated king retired to the forest. His son, being brought up in the forest, had to rule from Pratishthana. On, Vikramaditya invaded Ujjain and drove away from the Śakas. To commemorate this event, he started a new era called the "Vikrama era"; the Ujjain calendar started around 58–56 BCE, the subsequent Shaka era calendar was started in 78 CE at Pratishthana. The association of the era beginning in 57 BCE with Vikramaditya is not found in any source before the 9th century CE; the earlier sources call this era by various names, including Kṛṭa, the era of the Malava tribe, or Samvat. The earliest known inscription that calls the era "Vikrama" is from 842 CE.
This inscription of Chauhana ruler Chandamahasena was found at Dholpur, is dated Vikrama Samvat 898, Vaishakha Shukla 2, Chanda. The earliest known inscription that associates this era with a king called Vikramaditya is dated 971 CE; the earliest literary work that connects the era to Vikramaditya is Subhashita-Ratna-Sandoha by the Jain author Amitagati. For this reason, multiple authors believe that the Vikram Samvat was not started by Vikramaditya, who might be a purely legendary king or the title adopted by a king who renamed the era after himself. V. A. Smith and D. R. Bhandarkar believed that Chandragupta II adopted the title Vikramaditya, changed the name of the era to "Vikrama Samvat". According to Rudolf Hoernlé, the king responsible for this change was Yashodharman: Hoernlé believed that he conquered Kashmir, is the same person as the "Harsha Vikramaditya" mentioned in Kalhana's Rajatarangini. Earlier, some scholars believed that the Vikrama Samavat corresponded to the Azes era of the Indo-Scythian king King Azes.
However, this was disputed by Robert Bracey following the discovery of an inscription of Vijayamitra, dated in two eras. The theory seems to be now discredited by Falk and Bennett, who place the inception of the Azes era in 47–46 BCE; the traditional New Year of Vikram Samvat is one of the many festivals of Nepal, marked by parties, family gatherings, the exchange of good wishes, participation in rituals to ensure good fortune in the coming year. It occurs in mid-April each year, coincides with the traditional new year in Assam, Burma, Kerala, Manipur, Punjab, Sri Lanka, Tamil Nadu and Thailand. In addition to Nepal, the Vikram Samvat calendar is recognized in North and East India, in Gujarat among Hindus. Hindu religious festivals are based on a Luni-Solar calendar, not Solar calendar, based on Vikram Samvat. In North India, the new year in Vikram Samvat starts from the first day of Chaitra Skukla paksha. In Buddhist communities, the month of Baishakh is associated with Buddha's Birthday, it commemorates the birth and passing of Gautama Buddha on the first full moon day in May, except in a leap year when the festival is held in June.
Although this festival is not held on the same day as Pahela Baishakh, the holidays fall in the same month of the Bengali and Theravada Buddhist calendars, are related through the spread of Hinduism and Buddhism in the Indian subcontinent. In Gujarat, the day after Diwali is celebrated as the first day of the Vikram Samvat calendar, the first day of the month Kartik; the Vikrami era is an ancient calendar and has been used by Hindus and Sikhs. It is one of the several regional Hindu calendars that have been in use on the Indian subcontinent, it is based on twelve synodical lunar months and 365 solar days; the lunar new year starts on the new moon in the month of Chaitra. This day, known as Chaitra Sukhladi, is a restricted holiday in India; the Vikrami Samvat has been in use in the Indian subcontinent since ancient times, remains in use by the Hindus in north, w
The 3rd century was the period from 201 to 300 A. D. or C. E. In this century, the Roman Empire saw a crisis, starting with the assassination of the Roman Emperor Severus Alexander in 235, plunging the empire into a period of economic troubles, barbarian incursions, political upheavals, civil wars, the split of the Roman Empire through the Gallic Empire in the west and the Palmyrene Empire in the east, which all together threatened to destroy the Roman Empire in its entirety, but the reconquests of the seceded territories by Emperor Aurelian and the stabilization period under Emperor Diocletian due to the administrative strengthening of the empire caused an end to the crisis by 284; this crisis would mark the beginning of Late Antiquity. In Persia, the Parthian Empire was succeeded by the Sassanid Empire in 224 after Ardashir I defeated and killed Artabanus V during the Battle of Hormozdgan; the Sassanids went on to subjugate many of the western portions of the declining Kushan Empire. In China, the chaos, raging since 189 would continue to persist with the decisive defeat of Cao Cao at the Battle of Red Cliffs in 208, which would end the hopes of unification and lead to the tripartite division of China into three main empires.
In India, the Gupta Empire was on the rise towards the end of the century. Korea was ruled by the Three Kingdoms of Korea. Japan entered the Kofun period; the Xiongnu formed the Tiefu state under Liu Qubei. The Southeast Asian mainland was dominated by Funan. At about this time in Sub-Saharan Africa, the Bantu expansion reached Southern Africa. In Pre-Columbian America, the Adena culture of the Ohio River valley declined in favor of the Hopewell culture; the Maya civilization entered its Classic Era. After the death of Commodus in the late previous century the Roman Empire was plunged into a civil war; when the dust settled, Septimius Severus emerged as emperor. Unlike previous emperors, he used the army to back his authority, paid them well to do so; the regime he created is known as the Military Monarchy as a result. The system fell apart in the 230s, giving way to a fifty-year period known as the Military Anarchy or the Crisis of the Third Century, following the assassination of the 28-year-old emperor Severus Alexander, where no fewer than twenty emperors held the reins of power, most for only a few months.
The majority of these men were assassinated, or killed in battle, the empire collapsed under the weight of the political upheaval, as well as the growing Persian threat in the east. Under its new Sassanid rulers, Persia had grown into a rival superpower, the Romans would have to make drastic reforms in order to better prepare their state for a confrontation; these reforms were realized late in the century under the reign of Diocletian, one of them being to divide the empire into an eastern and western half, have a separate ruler for each. Early 3rd century – Burial in catacombs becomes common place. 208: the Chinese naval Battle of Red Cliffs occurs. 211 – 217: Caracalla, Roman Emperor. 212: Constitutio Antoniniana grants citizenship to all free Roman men. 212 – 217: Baths of Caracalla. 220: The Han Dynasty comes to an end with establishment of the Three Kingdoms in ancient China. 220 – 280: The Three Kingdoms period. 222 – 235: Alexander Severus, Roman Emperor. 224: Ardashir I of the Sassanid dynasty conquers the Parthian empire at the Battle of Hormozdgān.
230 – 232: Sassanid dynasty of Persia launches a war to reconquer lost lands in the Roman east. 234: Zhuge Liang dies of illness at the standoff of Wuzhang Plains. 235 – 284: Crisis of the Third Century shakes Roman Empire. 241: The Kingdom of Araba dissolved after the Fall of Hatra to Persia 244: Battle of Xingshi in China. 250 – 538: Kofun era, the first part of the Kofun period in Japan. 258: Valerian's massacre of Christians. 260: Roman Emperor Valerian I is taken captive by Shapur I of Persia. 263: Cao Wei conquers the Shu Han Kingdom. 266: The Jin Dynasty is founded after the overthrow of the Cao Wei Dynasty by Sima Yan. 280: The Jin Dynasty reunites China under one empire after the conquest of Eastern Wu. 284 – 305: Diocletian, Roman Emperor. 291 – 306: The War of the Eight Princes, a civil war by the Sima Clan in China. Sarnath becomes a center of Buddhist arts in India. Diffusion of maize as a food crop from Mexico into North America begins; the Kingdom of Funan reaches its zenith. The Goths move from Gothiscandza to Ukraine.
Menorahs and Ark of the Covenant, wall painting in a Jewish catacomb, Villa Torlonia, are made. The Coptic period begins. Siddhartha in the Palace, detail of a relief from Nagarjunakonda, Andhra Pradesh, India, is made. Andhra period; the artwork is now kept at New Delhi. Jonah Swallowed and Jonah Cast Up, two statuettes of a group from the eastern Mediterranean Asia Minor, are made. Now kept at The Cleveland Museum of Art; the Magerius Mosaic is made. Late 3rd century-early 4th century – Good Shepherd and Story of Jonah, painted ceiling of the Catacombs of Marcellinus and Peter in Rome, is made. Ardashir I, founder of the Sasanid Empire Artabanus V, last ruler of the Parthian Empire Aurelian, Roman emperor Clement of Alexandria, Christian head of Catechetical School of Alexandria Cao Ca
The Buddhist calendar is a set of lunisolar calendars used in mainland Southeast Asian countries of Cambodia, Laos and Thailand as well as in Sri Lanka and Chinese populations of Malaysia and Singapore for religious or official occasions. While the calendars share a common lineage, they have minor but important variations such as intercalation schedules, month names and numbering, use of cycles, etc. In Thailand, the name Buddhist Era is a year numbering system shared by the traditional Thai lunisolar calendar and by the Thai solar calendar; the Southeast Asian lunisolar calendars are based on an older version of the Hindu calendar, which uses the sidereal year as the solar year. One major difference is that the Southeast Asian systems, unlike their Indian cousins, do not use apparent reckoning to stay in sync with the sidereal year. Instead, they employ their versions of the Metonic cycle. However, since the Metonic cycle is not accurate for sidereal years, the Southeast Asian calendar is drifting out of sync with the sidereal one day every 100 years.
Yet no coordinated structural reforms of the lunisolar calendar have been undertaken. Today, the traditional Buddhist lunisolar calendar is used for Theravada Buddhist festivals, no longer has the official calendar status anywhere; the Thai Buddhist Era, a renumbered Gregorian calendar, is the official calendar in Thailand. The calculation methodology of the current versions of Southeast Asian Buddhist calendars is based on that of the Burmese calendar, in use in various Southeast Asian kingdoms down to the 19th century under the names of Chula Sakarat and Jolak Sakaraj; the Burmese calendar in turn was based on the "original" Surya Siddhanta system of ancient India. One key difference with Indian systems is that the Burmese system has followed a variation of the Metonic cycle, it is unclear from where, how the Metonic system was introduced. The Burmese system, indeed the Southeast Asian systems, thus use a "strange" combination of sidereal years from Indian calendar in combination with the Metonic cycle better for tropical years.
In all Theravada traditions, the calendar's epochal year 0 date was the day in which the Buddha attained parinibbāna. However, not all traditions agree on when it took place. In Burmese Buddhist tradition, it was 13 May 544 BCE, but in Thailand, it was 11 March 545 BCE, the date which the current Thai lunisolar and solar calendars use as the epochal date. Yet, the Thai calendars for some reason have fixed the difference between their Buddhist Era numbering and the Christian/Common Era numbering at 543, which points to an epochal year of 544 BCE, not 545 BCE. In Myanmar, the difference between BE and CE can be 543 or 544 for CE dates, 544 or 543 for BCE dates, depending on the month of the Buddhist Era. In Sri Lanka, the difference between BE and CE is 544; the calendar recognizes two types of months: sidereal month. The Synodic months are used to compose the years while the 27 lunar sidereal days, alongside the 12 signs of the zodiac, are used for astrological calculations; the days of the month are counted in two halves and waning.
The 15th of the waxing is the civil full moon day. The civil new moon day is the last day of the month; because of the inaccuracy of the calendrical calculation systems, the mean and real New Moons coincide. The mean New Moon precedes the real New Moon; as the Synodic lunar month is 29.5 days, the calendar uses alternating months of 29 and 30 days. Various regional versions of Chula Sakarat/Burmese calendar existed across various regions of mainland Southeast Asia. Unlike Burmese systems, Lan Na, Lan Xang and Sukhothai systems refer to the months by numbers, not by names; this means reading ancient texts and inscriptions in Thailand requires constant vigilance, not just in making sure one is operating for the correct region, but for variations within regions itself when incursions cause a variation in practice. However, Cambodian month system, which begins with Margasirsa as the first month, demonstrated by the names and numbers; the Buddhist calendar is a lunisolar calendar in which the months are based on lunar months and years are based on solar years.
One of its primary objectives is to synchronize the lunar part with the solar part. The lunar months twelve of them, consist alternately of 29 days and 30 days, such that a normal lunar year will contain 354 days, as opposed to the solar year of ~365.25 days. Therefore, some form of addition to the lunar year is necessary; the overall basis for it is provided by cycles of 57 years. Eleven extra days are inserted in every 57 years, seven extra months of 30 days are inserted in every 19 years; this provides 20819 complete days to both calendars. This 57-year cycle would provide a mean year of about 365.2456 days and a mean month of about 29.530496 days, if not corrected. As such, the calendar adds an intercalary month in leap years and sometimes an intercalary day in great leap years; the intercalary month not only corrects the length of the year but corrects the accumulating error of the month to extent of half a day. The average length of the month is further corrected by adding a day to Nayon