Kolkata: This Durga Puja saw two days of Saptami according to Surya Siddhanta (Gupta Press almanac) and two days of Shashti according to Drik Siddhanta (Bisuddha Siddhanta almanac). Next year, both almanacs are expected to converge in observing two days of Ashtami during Durga Puja.But 2028 holds a major surprise, with the two almanacs likely to place Durga Puja on two different timelines. Those following Bisuddha Siddhanta almanac, including Belur Math, are expected to observe Durga Puja from Sept 23 to Sept 27. A vast majority of others, including most community pujas and traditional household pujas that follow Surya Siddhanta, are likely to conduct Durga Puja sometime between Oct 8 and Oct 12.Swami Gurudasanandaji of Ramakrishna Mission, who is associated with the puja rituals, said that while the exact dates were yet to be determined, the two schools — Bisuddha Siddhanta and Surya Siddhanta — may witness a gap of two to three weeks between the puja dates. “Now, calculation for pujas in 2027 is underway,” the RKM senior monk said.Surya Siddhanta is a Sanskrit treatise on Indian astronomy attributed to Latadeva, a student of Aryabhatta, and dated by most modern scholars to sometime between the late 4th and 5th centuries. Bisuddha Siddhanta, or Drik Siddhanta, was introduced in 1890 by mathematician Madhab Chandra Chattopadhyay to account for changes in planetary positions that had occurred over centuries. It relies on modern astronomical computations.“As per available information, Durga Puja in 2028 is going to be truly unique with the two primary treatises — Surya Siddhanta and Bisuddha Siddhanta — scheduling the puja a fortnight apart. According to almanac experts, this 15-day difference between the two systems is caused by a unique planetary shift,” said Jayanta Kushari, principal of Sarba Bharatiya Prachya Vidya Academy, which has been conducting workshops on traditional customs and rituals ahead of puja for the past four decades.The disparity comes down to how the two schools calculate the exact entry of the sun into zodiac signs, or Sankranti, and how they define the boundaries of lunar months. While Drik relies on the exact observable positions of the moon and the sun, Surya Siddhanta uses formulae dating back centuries. When a lunar cycle spans the cusp of these calculations, one school triggers a shift in the festival month while the other does not. The gap will be so distinct that when one calendar is celebrating Maha Navami, the other will be marking an entirely different phase of the moon.The disparity was even greater on two previous occasions — in 1963 and 1982. In both years, Belur Math and Ramakrishna Mission observed Durga Puja a month before those following Gupta Press almanac. On both occasions, the former held the puja in Ashwin while the latter observed it in Kartik. The difference in calculation was due to the mala maash, or impure month, falling in the intervening period.The two govts then in office — the PC Sen-led Congress govt in 1963 and the Jyoti Basu-led Left Front govt in 1982 — declared the puja holidays according to Surya Siddhanta almanac, as it is the one widely followed in the state. However, on both occasions, govt orders specified that employees seeking leave on puja days as decreed by Bisuddha Siddhanta almanac would also be allowed to do so.
