A researcher raised a concern….
“Which is why back-calculation errors might throw the dates off tremendously, when the results are taken to be correct today.”
This is correct. This is always a possibility. And this is what makes my theory and corresponding inferences….falsifiable, and hence ‘scientific’.
I should remind you of your ‘astute’ observation that ‘reasonable back calculations are possible based on knowledge of ‘precession of equinoxes’
Well, That is how I defined ‘approximately right‘ ranges for the events of Mahabharata (All observations related to Bhishma Nirvana) and also Ramayana ( 4 specific observations only governed by the phenomenon of ‘precession of equinoxes’ and having nothing to do with planets).
Mahabhrarata – Plausible range based on AV observation and other observations due to precession of equinoxes
[~7000 BCE – 4508 BCE]
Ramayana – Four observations of Chaitra and season, Ashwin and season, Abhijit as pole star and Sun setting on nakshatra Pushya during the Hemant season
[10500 BCE – 15000 BCE]
Note: In case of Ramayana, these are the latest date. There is nothing in the astronomy evidence that would stop one from going back in antiquity to other such intervals, defined by precession of equinoxes, occurring every ~26000 years.
I did place a limit of 50,000 BCE as the upper limit on the timing of Ramayana, based on hydrology evidence (Clift Peter et al , 2012).
Let’s couple this with your next observation…
The ancient Indians do seem to have had a comprehensive database.e.g., see this: (PDF file)http://220.127.116.11:12000/jspui/bitst … ayanan.pdf The Manda Puzzle in Indian Astronomy, Anil Narayanan, 2012 Indian Journal of History of Science, 47.3 (2012) 317-343 IMO, it is a speculative paper, but promising.
While you are at it, you may want to (if you have not done it, already) read 3 of his other papers. Equally promising.
When we couple these two, this may lead to the conclusion…
That some poet might have used this extensive knowledge of astronomy, prevalent in India, during (pick anytime of your choice… 500 CE through 500 BCE or before) this period, to write massive science fiction(s) [Ramayana and Mahabharata]….
If so, we can think of two scenarios…
(1) The poet wrote it from scratch, with ingenious usage of astronomy observations spread across the epics. 215+ in case of Mahabharata and 575+ in case of Ramayana. Granted his calculations did generate errors in few cases (about 5+ in case of Mahabharata and about 25+ in case of Ramayana).
(2) Or, the epics (Ramayana and Mahabharata) existed when this astronomer with able poetic skills decided to employ his/her astronomy knowledge of back calculations/precession of equinoxes and insert these astronomy observations, spread across these epics, with appropriate narrations. It was all done well.
My point is, I have considered these scenarios as possibilities (in my mind and in my books), and them as valid as Valmiki or Vyasa (and their assistants) making visual observations at the time of occurrence of Ramayana or Mahabharata, and then encoding them while writing these epics.
In first two scenarios (astronomer poet using astronomy data in writing of his fiction, or inserting astronomy couplets in already existing epics) all I can say is that these astronomy poets decided to build their fiction around some arbitrarily chosen time intervals (period fiction, period novels, like period films) around 6th millennium BCE (in case of Mahabharata) and 13th millennium BCE (in case of Ramayana).
In the second scenario (Valmiki or Vyasa noting down astronomy details in their writing of histories of their own times), the events described can be dated to 6th millennium BCE (Mahabharata) or 13th millennium BCE (Ramayana) based on numerous astronomy observations of the text. Granted, there are few (very small number.. <5% in both cases) astronomy observations from the epics that conflict with these time frames, but that also means they conflict with rest of the 95% of astronomy observations. These could be due to various errors that epics are exposed too through the passages of times – translation, transliteration, transposition, loss of text, additional commentaries getting incorporated as part of the text, interpolation etc.