The conflict of disciplines as evident in the Islamic calendar is because Islam follows a lunar calendar of 354 days, and is, therefore, naturally out of sync with the seasons
Ramazan, the ninth month of the Islamic Calendar, began on May 16 and will conclude on June 14. Considered to be the most sacred month, its span is coeval with keeping Roza (obligatory fasting), salat-ul-nafl (supererogatory prayers), recitation of Quran and participation in social services. At the end of Ramazan comes the festival of Id-ul-Fitr.
Most non-Muslims, having known that festivals and sacred days are rooted in seasons, are confounded on Ramzan. A few recollect that it once came in the summer, others recount it came in winter, and still others in Monsoon. In reality, everyone is correct, but none so fully. Since Islam follows a lunar calendar of 354 days, it is naturally out of sync with the seasons. The months rotate freely throughout the year, regressing 10 to 11 days on every successive occasion vis-à-vis the Gregorian calendar.
The phenomenon differs widely from the ‘floating’ dates of Hindu festivals and sacred occasions familiar to us in India. The dates of Navaratri, Ram Navami, Rath Yatra, Janmasthami among others vary from year-to-year whether seen from the Gregorian calendar or any Indian sidereal solar calendar. The Hindu festivals, though determined by tithis or lunar phases, are not without reference to solar months. Thus, Ram Navami always falls in Chaitra, Buddha Purnima in Vaishak, Rath Yatra in Aashadh, Janmasthami in Shravana, Durga Puja in Asvin, though actual dates differ year-on-year. They oscillate exactly like a pendulum, falling back twice into equilibrium position over a nine-year cycle.
Reckoning the month by the moon has been an ancient practice around the world. In fact, the English word ‘month’ is believed to have been etymologically derived from the moon, though there is no correlation between the two in the Gregorian calendar. Actually, the moon is a more convenient marker than the sun. This because while the daily angular motion of the sun, relative to the fixed stars, is only about 1 degree, that of the moon is 13 degrees. Being a nocturnal fixture, it is easier to track the sidereal movement of the moon. The sidereal revolution period of the moon, or the average time it takes to circuit the distance from a given star back again to same star, is around 27 days seven hours and 43 minutes. But the synodic revolution, or Moon’s actual revolution around the earth takes around 53 hours or more because of the eastward motion of the sun which must be overtaken. One synodic revolution of the moon around the earth takes 29 days and 12 hours and 44 minutes ie, 29.53 days. This is the time period between one new moon to the next, constituting a single lunar month.
But while lunar month is a reality, a lunar year is just a mental construct. A lunar year comprising 29.5 days x 12 = 354 days, unlike the solar year of 365.25 days, has no grounding in any astronomical phenomenon. The solar year of 365.25 days stands for the time taken by the earth to revolve around the sun once. During this course of revolution, the sun passes against a background of fixed stars at the rate of one zodiac per month. But it would be utterly wrong to impose the same model of moon. The moon actually covers all the zodiacs within one month (actually less, 27 days and seven hours on an average) while revolving round the earth.
Historically, civilisations like the Babylonians, which used lunar month, inserted an extra month called ‘intercalary month’ at definite intervals to keep their calendar at par with the solar year. This prevented seasonal cycles from going haywire. This is the procedure still followed in the case of Vikram Samvat, where every third year a supplementary month (adhimas) is inserted. This makes Vikram Samvat different from Hijri Islamic Calendar though both use amanta (starting at new moon and ending on no moon) system of month reckoning.
In pre-Islamic Arabia, such a luni-solar calendar had been adopted in 412 AD. Every third year, an intercalary month (‘Nasi’) was placed between Zu al-Hijja (the month of pilgrimage to Mecca) and Muharram the first month of the year. But the system was prohibited by two verses of the Quran vide Sura 9 Aayat 36 and 37. An astronomical issue became an inalienable religious issue. Since then the Muslim calendar became 354 days long, thus out of sync with seasonal cycle.
A calendar is, therefore, not meant merely for religious observances but also for civilian, agricultural and revenue purposes. A purely lunar calendar might still have worked in Arabian Peninsula, which has scant agriculture. But as Islam began to spread, as a result of its military conquest, insufficiencies of lunar year came to light.
Thus at height of its glory three Islamic Empires viz, Turkish Ottoman Empire, Safavid Empire in Iran and Mughal Empire in India had either fashioned a workable solar calendar or using solar calendars of pre-Islamic vintage. In Iran, the celebrated astronomer, poet and philosopher Omar Khayyam (1048-1132 AD) was amongst eight wise men engaged by Seljuk ruler Jalal al-Din Malik Shah (ruled 1072-1092) to fashion a new solar calendar, with new era and with new names for the months. The Jalali Era (Tarikhi-i Jalali) adopted on the March 15, 1079. ‘A computation of time’ says Edward Gibbon, ‘which surpasses the Julian and approaches the accuracy of the Gregorian style’. In modern Persia, the Jalali calendar became the official calendar in 1911. In fact, in 1976, Shah Mohammed Reza Pehalvi had had changed the era from Hijri (622 AD) to Cyrus the Great’s coronation (559 BC), but it was reverted to Hijri after the Islamic Revolution in 1979. In India Akbar also adopted the Persian solar calendar for administrative use, which was later overturned by Aurangzeb.
Tipu Sultan (ruled 1782-1799) of Mysore, who set up a new calendar with a new era (Maulud-i-Muhammed) beginning from 609 AD (Mohammed’s proclamation of prophethood), used months with new Arabic names but intercalary months, something prohibited in the Quran. The conflict of theology and astronomy is evident in the Islamic calendar.
(The author is an independent researcher. Views expressed above are personal)
