Hindu calendar
Similarly, the ancient Jain traditions have followed the same lunisolar system as the Hindu calendar for festivals, texts and inscriptions.
However, the Buddhist and Jain timekeeping systems have attempted to use the Buddha and the Mahavira's lifetimes as their reference points.
[16][17][18] This study is one of the six ancient Vedangas, or ancillary science connected with the Vedas – the scriptures of Vedic Sanatan Sanskriti.
[16][17] Yukio Ohashi states that this Vedanga field developed from actual astronomical studies in ancient Vedic Period.
[19][20] The texts of Vedic Jyotisha sciences were translated into the Chinese language in the 2nd and 3rd centuries CE, and the Rigvedic passages on astronomy are found in the works of Zhu Jiangyan and Zhi Qian.
[23] Hindu scholars kept precise time by observing and calculating the cycles of Surya (the Sun), Moon and the planets.
These calculations about the Sun appear in various astronomical texts in Sanskrit, such as the 5th-century Aryabhatiya by Aryabhata, the 6th-century Romaka by Latadeva and Panca Siddhantika by Varahamihira, the 7th-century Khandakhadyaka by Brahmagupta and the 8th-century Sisyadhivrddida by Lalla.
[25][26][27] For example, the 1st millennium CE Hindu scholars calculated the sidereal length of a year as follows, from their astronomical studies, with slightly different results:[28] The Hindu texts used the lunar cycle for setting months and days, but the solar cycle to set the complete year.
[4][29] They tracked the solar year by observing the entrance and departure of Surya (sun, at sunrise and sunset) in the constellation formed by stars in the sky, which they divided into 12 intervals of 30 degrees each.
In their pursuit of accurate tracking of relative movements of celestial bodies for their calendar, they had computed the mean diameter of the Earth, which was very close to the actual 12,742 km (7,918 mi).
These, in turn, were based in the astronomical tradition of Vedāṅga Jyotiṣa, which in the preceding centuries had been standardised in a number of (non-extant) works known as Sūrya Siddhānta.
[citation needed] Hinduism and Buddhism were the prominent religions of southeast Asia in the 1st millennium CE, prior to the Islamic conquest that started in the 14th century.
[32] The names of month and festivals of Balinese Hindus, for the most part, are different, though the significance and legends have some overlap.
Many variants of the Hindu calendar have been created by including and excluding these elements (solar, lunar, lunisolar etc.)
The amanta (also known as Amāvasyānta or Mukhyamana) tradition is followed by most Indian states that have a peninsular coastline (except Assam, West Bengal, Odisha, Tamil Nadu and Kerala, which use their own solar calendars).
Nepal and most Indian states north of the Vindhya mountains follow the poornimānta (or Gaunamana) tradition.
[44] The presence of this system is one of the factors considered in dating ancient Indian manuscripts and epigraphical evidence that have survived into the modern era.
[44][45] The two traditions of Amanta and Purnimanta systems have led to alternate ways of dating any festival or event that occurs in a Krishna paksha in the historic Hindu, Buddhist or Jain literature, and contemporary regional literature or festival calendars.
A few major calendars are summarized below: or بیساکھ [beːsaːkʰ] or وِهاءُ, vihāu [zeːʈʰ] [haːr] or آهاڙُ, āhāṛu or بَڊرو, baḍro [əːʃid] [kaːrtikʰ] or مَنگهِرُ, manghiru or پۄہ [pɔh] [maːg] [pʰaːgun] Twelve Hindu mas (māsa, lunar month) are equal to approximately 354 days, while the length of a sidereal (solar) year is about 365 days.
The twelve months are subdivided into six lunar seasons timed with the agriculture cycles, blooming of natural flowers, fall of leaves, and weather.
The choice of this month was not random, but timed to sync back the two calendars to the cycle of agriculture and nature.
[47] The Hindu mathematicians who calculated the best way to adjust the two years, over long periods of a yuga (era, tables calculating 1000s of years), they determined that the best means to intercalate the months is to time the intercalary months on a 19-year cycle, similar to the Metonic cycle used in the Hebrew calendar.
The Hindu calendars adjust the mismatch in divasa and tithi, using a methodology similar to the solar and lunar months.
[51] A tithi is technically defined in Vedic texts, states John E. Cort, as "the time required by the combined motions of the Sun and Moon to increase (in a bright fortnight) or decrease (in a dark fortnight) their relative distance by twelve degrees of the zodiac.
[52] These motions are measured using a fixed map of celestial zodiac as reference, and given the elliptical orbits, a duration of a tithi varies between 21.5 and 26 hours, states Cort.
[52] However, in the Indian tradition, the general population's practice has been to treat a tithi as a solar day between one sunrise to next.
The technical standard makes each tithi contain different number of hours, but helps the overall integrity of the calendar.
[55] آچَرُ or Ārtvāru آرتوارُ سُومَرُ or Pīr پیر بوموار or [bɔ̃waːr] بۄنٛوار مَنگلُ or Angāro اَنڱارو بۄدوار ٻُڌَرُ or Arbā اَربع or Brihaspativāra बृहस्पतिवार برَٛسوار or [brʲaswaːr] برٛؠسوار وِسپَتِ or Khamīsa خَميِسَ or Jume'rāt جمعرات or bhṛguvāsarah भृगुवासर شۆکُروار or [jumaːh] جُمعہ شُڪرُ or Jum'o جُمعو or Juma'a جمع or Sthiravāsarah स्थिरवासर بَٹہٕ وار orŚaniccharvār ਸ਼ਨਿੱਚਰਵਾਰ orSaniccharvār ਸਨਿੱਚਰਵਾਰ orSanīvār ਸਨੀਵਾਰ ڇَنڇَرُ or Śanscharu شَنسچَرُ or Haftah ہفتہ The term -vāsara is often realised as vāra or vaar in Sanskrit-derived and influenced languages.
To be precise, a karaṇa is the time required for the angular distance between the Sun and the Moon to increase in steps of 6° starting from 0°.
[59] The dates of the lunar cycle based festivals vary significantly on the Gregorian calendar and at times by several weeks.
