The Gregorian calendar, also called the Western calendar and the Christian calendar, is internationally the most widely accepted and used civil calendar. The Gregorian calendar is a ‘solar’ calendar. A regular Gregorian year consists of 365 days and in a leap year, an intercalary or leap day is added as February 29th, making the year 366 days.
The Indian calendar Reform Committee, under the chairmanship of Professor Meghnad Saha, was founded in November 1952. It identified more than 30 calendars, all variants of the Surya Siddhanta calendar, in use across different states in India.
The Prime Minister, Jawaharlal Nehru, said, “Now that we have attained Independence, it is obviously desirable that there should be a certain uniformity in the calendar for our civic, social and other purposes and that this should be based on a scientific approach to the problem.”
Lunar days in the Hindu calendar are called tithis. A tithi is the time taken for the longitudinal angle between the moon and the sun to increase by 12 degrees.
The calendar is ingeniously based on both the sun and the moon. It uses a solar year but divides it into 12 lunar months. A lunar month is precisely 29 days, 12 hours, 44 minutes and three seconds long. Twelve such months constitute a lunar year of 354 days, eight hours, 48 minutes and 36 seconds. To help the lunar months coincide with the solar year, the practice of inserting an intercalary (extra) month arose.
The use of the lunar or moon’s position to determine religious festivals and dates is one of the major factors in the variation of these festivals and dates from one year to another. However, this reliance on the lunar or moon position to determine Hindu religious festivals is not unique to the Hindu.
A factor to be considered is the basic difference between the English date and the Hindu date. The English date and the day changes at midnight, whereas the Hindu date changes at sunrise. The Hindu day lasts from one sunrise to another.
According to the Hindu Vedic Astrologers, the ‘Panchang’ formed by two words, ‘Panch,” and ‘Ang.’ ‘Panch’ means five and ‘Ang’ means limbs. Therefore, ‘Panchang’ means five limbs. The ‘Panchang’ is a book that lists the days of every month with astronomical data and calculations. On the basis of the data, the days of Hindu festivals, religious and auspicious occasions are fixed.
Therefore, the tithi and the position of the planets are calculated based on Universal Time (UT) and must be converted according to the respective time-zones to reflect the local standard time.
As such, an event (such as an eclipse), or a festival (such as Divali), will take place at the same Universal Time, but will be seen or celebrated at different times, depending on the time zone where one is located.
For example, India is nine and a half hours ahead of T&T because of the different time-zone each country is located in. Therefore, when it is 9 pm on Saturday in T&T, it will be 6.30 am on Sunday in India.
As festivals are determined based on the lunar day or tithi, and its relation to a sunrise/sunset, the difference between sunrise and sunset times in T&T and India will naturally lead to differences in the times when both countries may observe a particular festival.
Some people with little knowledge of Hindu astrology have been questioning Maha Sabha’s declaration and advice to Cabinet on what day Divali will occur and the public holiday observed.
The Islamic calendar is a lunar calendar and months begin when the first crescent of a new moon is sighted, since the Islamic lunar calendar year is shorter than the solar year and contains no intercalation throughout the seasons.
Many Muslims insist on the local physical sighting of the moon to mark the beginning of Ramadan, but others use the calculated time of the new moon or the Saudi Arabian declaration to determine the start of the month. Since the new moon is not in the same state at the same time globally, the beginning and ending dates of Ramadan depend on what lunar sightings are received in each respective location.
Therefore, the use of lunar considerations to determine religious observances is a common thread throughout the three main religions of the world – Christianity, Islam and Hinduism.
