Harivansh (Vishnu Purana A. 5) states that when Nanda carried Krishna
to Gokul on Shravan Vadya Navami day, there was dry cow-dung spread all
over the ground and trees were cut down. The presence of Dry Cowdung all
over in Gokul indicates the presence of Summer in the month of Shravan.
Trees are usually cut down in Summer to be used as fuel in the rainy season.
The seasons move one month backwards in two thousand years. Today the rainy
season starts in Jeshtha but two thousand years ago, at the time of KaIidas,
rainy season used to start in Ashadha. At the time of Krishna's birth the
Summer was in the month of Shravan while today it is in Vaishakha. Thus
the summer is shifted by four months, hence Krishna's period comes to 4x2000
= 8000 years ago approximately. This means about 6000 years B.C., the same
period we have seen above.

At the time of Mahabharat, the Vernal Equinox was at Punarvasu. Next
to Punarvasu is Pushya Nakshtra. Vyas used "Pushyadi Ganana"
for his Sayan method, and called Nirayan Pushya as Sayan Ashvini. He shifted
the names of further Sayan Nakshtras accordingly. At that time Winter Solstice
was on Revati, so Vyas gave the next Nakshatra Ashvini the first palee
in the Nirayan list of Nakshatras. Thus he used Ashvinyadi Ganana for the
Nirayan method. Using at times Sayan names and at times Nirayan names of
the Nakshatras, Vyas prepared the riddles. By the clue that Nirayan Pushya
means Sayan Ashvini, it is seen that Nirayan names of Nakshatras are eight
Nakshatras ahead of the Sayan names Thus the Saturn in Nirayan Purva, and
Sayan Rohini, Jupiter was in Nirayan Shravan, and Sayan Swati (near Vishakha),
while the Mars was in Nirayan Anuradha, and Sayan Magha, Rahu was between
Chitra and Swati, by Sayan way means it was in Nirayana. Uttara Ashadha
(8 Nakshtras ahead). From these positions of the major planets we can calculated
the exact date. My procedure is as follows:

I found out that on 5th May 1950, the Saturn was in Purva Phalguni.
From 1950 I deducted 29.45 years to get the year 1920 when the Saturn was
again in Purva. In this way I prepared a vertical column of the years when
the Saturn was in Purva. Similarly, I prepared vertical columns of the
years when the Jupiter was in Shravan and Rahu in Uttara Ashadha. Then
I searched in horizontally to find out the year common in all the three
columns. It was 5561-62 B.C. when all the three great planets were at the
required places. Then I proceded for the detailed calculations.

Bhisma expired at the onset of Uttarayan i.e. on 22nd December. This
is a fixed point according to the modern Scientific Calendar. He was on
the arrow-bed for 58 nights and he had fought for ten days. Hence 68 days
earlier than 22nd December the War had started. This shows that the War
started on 16th October. We have to calculate the plane- tary positions
of 16th October 5561 B.C.