वाक्यपञ्चाङ्गम्

  • For general context, see here.

History

  • In Shaka 444 i.e. 522 CE, mean longitudes of the Old SS and Aryabhatiya etc. tallied almost exactly with the so called sayana i.e. tropical mean longitudes of planets as per modern astronomy.
  • “These are thus works like Grahalaghva and Makaranda, both of them having been based on the Surya Siddhanta formulae with some insignificant “beeja corrections”.”
  • “There are several Vakya panchangams in Tamil nadu, the famous being the Pampu (snake) panchangam, Thanigai Panchangam, Sri Rangam Panchangam, Garudan Panchangam, Arcot Sitarama Iyer panchangam and so on. There will invariably be a difference in timings between drik Ganitha and Vakya Panchangam. But they invariably take the Drik calculation to show correct timings of eclipses (so that they make believe their system is ancient and also accurate). Some of them, especially Arcot Sita Rama Iyer panchangam, make some predictions about weather and politics that have proved accurate. May be a case of making correct predictions from wrong data.”
  • “There is a textual record that till as late as 1996 the most reputed panchanga-maker of Kashmir [Vijayeshwar-Panchang] was giving the timings of tithi, nakshatra etc. as per “Khaṇḍa-khādyaka” a sixth century ‘‘handbook” of Brahmagupta, for the last about 100 years whereas he had switched over to “drik-ganita” for planetary positions very recently then!"

Errors

  • Understanding precession in terms of trepidation (Details here.
  • vAkya-panchAnga-s oft give erroneous results regarding graha-s
    • This manifests in inability to precisely predicting eclipses. Hence, contemporary ritualists fully use dRk-panchAnga-s for grahaNa-observations.
    • Around Jan 6, 2018 conjunction of Mars and Jupiter could be observed while they placed Mars still in 1st qtr about 1½° (three moon sizes) away.
    • Apr 13, 2017: Vakya Panchanga said Budha supposedly in Ashvini 3rd qtr transited Surya in Bharani 4th qtr - but NASA showed Mercury passing Surya. TW
  • Wrong tithi boundaries.
    • June 21 2020 was a special day - it was the solstice day, there was an annular solar eclipse visible from India (with peak at 11:47:35 am IST), and it naturally was amAvAsyA until 11:47:35 am IST. vAkya-panchAnga-s had obvious errors with regards to sun-moon conjunction (and consequently eclipse and end of amAvAsyA) - so tithi junction was till 12:30 or so. Some ritualists simply followed pop culture and used more accurate dRk-panchAnga-s for eclipse observances; while following vAkya-panchanga regarding parva-rituals! Such inconsistency! So, they incorrectly conducted sthAlIpAka the following day. (Not to mention, they must have continued saying “uttarAyaNe” in their sankalpa-s as well.)
  • Sometimes saura-paxa-panchAnga-s are not even able to determine if an eclipse will “happen” or not.
  • “The word “sankalpa” reminds me that we recite the daily “samkalpa” about Kalpa, Manvantara, Yuga, varsha etc. as per the Surya Siddhanta (instead of Aryabhatiya!!) but do not calculate even our horoscopes from the same work.”

Error correction

  • अयनचलनप्रतिक्रिया दृक्तुल्यताप्राधान्यम् च अन्यत्र+ उक्तम्।
  • shankAr dIxit and the shrautin of Colaba MT_TW
  • raghunAthAchAri, [MT].
    • gave several public lectures in Chennai to attempt to increase the awareness of Hindus on modern astronomy and the importance of first hand and meticulous observations
    • “discussed the importance of modern astronomy with the ācarya of the Sriperumbudur śrīvaiṣṇava maṭha and convinced him to adopt a modern astronomical almanac, "
    • “demonstrated to his Vedic ritualist friends, Venkateshvara Dikshita and Sundaresha Shrautin, that the astronomical tables of the traditional astronomers of Andhra and Dramiḍa were otiose and that they badly mis-predicted basic astronomical events which are central to Vaidika rituals”
    • “during the solar eclipse of August 18, 1868 raghunAthAchAri was able to demonstrate his predictions: He got the eclipse time correct with an error of 12 seconds using calculations done by his hand while the traditional astronomers performed dismally with a whopping 24 minute error. This had a strong effect and many traditional Hindus now switched over to his side. He then demolished the most recalcitrant traditional astronomers in a sadas of brāhmaṇa-s of the Dramiḍa country. Seeing this the Śaṃkara maṭha sent out a circular stating that the Vedic ritualists Venkateshvara Dikshita and Sundaresha Shrautin were correct in adopting modern theory and techniques for their rituals. His efforts were paralleled by those of Ketkar in Maharashtra and Venkatakrishna Raya in Andhra to get the Hindus to use modern astronomical calculations.”