Bengali calendar
The Bangla calendar also known as Bônggabdo in the Bengali language, is the traditional calendar used in Bangladesh and Bangla-speaking regions of India. The calendar is based on the solar year. New Year's Day falls between 13 April and 15 April.
History
Under the Mughals, agricultural taxes were collected according to the Hijri calendar. However, as the Hijri calendar is a lunar calendar, the agricultural year did not coincide with the fiscal year. Therefore, farmers were hard-pressed to pay taxes out of season. In order to streamline tax collection, the Mughal Emperor Akbar ordered a reform of the calendar. Accordingly, Fatehullah Shirazi, a renowned scholar and astronomer, formulated the Bangla year on the basis of the lunar Hijri and Bangla solar calendars. The new Fasli San (agricultural year) was introduced on 10/11 March 1584, but was dated from Akbar's accession to the throne in 1556. The new year subsequently became known as Bônggabdo, or Bengali year.
Organization
Months
| Mash Month |
Kal Season |
|---|---|
| Boishakh April-May |
Grishsho Summer |
| Joishţho May-June | |
| Ashaŗh June-July |
Bôrsha Rainy |
| Srabon July-August | |
| Bhadro August-September |
Shôrot Autumn |
| Ashshin September-October | |
| Kartik October-November |
Hemonto Dry |
| Ôgrohaeon November-December | |
| Poush December-January |
Sheeth Winter |
| Magh January-February | |
| Falgun February-March |
Bôshonto Spring |
| Choitro March-April |
Length
The length of a year in the Bangla calendar, as in the Gregorian calendar, is counted as 365 days. However, the actual time taken by the earth in its revolution around the sun is 365 days 5 hours 48 minutes and 47 seconds. To make up this discrepancy, the Gregorian calendar adds an extra day, Leap Year, to the month of February every fourth year (except in century years and not divisible by 400). The Bangla calendar, which was based on astronomical calculations, did not make this extra leap year adjustment. Bangla months too were of different lengths. In order to counter this discrepancy and make the Bangla calendar more precise, a committee to reform the Bangla calendar was set up on 17 February 1966 under the auspices of the Bangla Academy and the guidance of Muhammad Shahidullah. According the recommendations of the committee, the months from Boishakh to Bhadro were to be counted as of 31 days each, while the months from Ashshin to Choitro were to be considered as of 30 days. The revised calendar is officially adopted in Bangladesh. However it is not followed in the neighbouring state of West Bengal, India where the old calendar continues to be followed.
Leap Year
According to the new calendar system, Falgun (which begins mid-February) has 31 days every four years. To keep pace with the Gregorian calendar, the Bônggabdo leap years are those whose corresponding Gregorian calendar year is counted as a leap year. For example, Falgun 1410 was considered a Bônggabdo leap month, as it fell during the Gregorian leap month of February 2004.
Revised and non-revised versions
The first of Boishakh, Pôhela Boishakh, is the Bengali New Year's Day. In Bangladesh, it is celebrated on April 14 every year according to the reformed calendar prepared by the Bangla Academy. However, since the people of the West Bengal follow the previous non-reformed calendar (which is not fixed with respect to the Western calendar), Indian Bengalis celebrate New Year's Day (Pôhela Boishakh) on April 15.
In West Bengal, India the Bengalis follow a Sidereal Solar calendar unlike in where the reformed calendar is to follow tropical solar year like Gregorian Calendar. The mathematical difference between the Sidereal and the Tropical calendar amounts to the difference of starting the new year in Bangladesh and West Bengal, India. Because of this the length of the months are also not fixed in Bengal Sidereal calendar, but rather based on the true movement of the sun.
Beginning of day
In the Bengali calendar, the day begins at sunrise, unlike in the Gregorian calendar, where the day starts at midnight.
Usage
In everyday use, the Bangla Calendar has been largely replaced with the Gregorian Calendar in Bengali-speaking regions, although it is still essential for marking holidays specific to Bengali culture (e.g. Pôhela Boishakh, Durja Puja, etc.), and for marking the seasons of the year (e.g. the monsoon, winter, etc.), and is thus recognized by the Bangladeshi government for the observation of public holidays. Almost every Bangla and English-language newspapers in Bangladesh and West Bengal print the day's date according to the Bangla Calendar alongside the corresponding date in the Gregorian Calendar. Many newspapers in Bangladesh also add a third calendar (the Islamic Calendar) to the date. In Bangladesh, it is not at all uncommon to find the date written three times (e.g. "25 Falgun 1412, 17 Muharram 1427, 27 February 2006") under the newspaper title.