Mahabharata War is important in two ways. it is a PAN Bharatian event where almost all the regions of Bharat participated in it. Secondly, Purana describes the chronology of three Kingdoms, Kuru, Ikshvaku in which 24th Princess was Gautama Buddha and Magadha of Rajagriha since Mahabharata period. Kaliyuga Raja Vriddhanta gives the chronology of the Magadha Kingdom from Mahabharata War up to Gupta period.

Hence the date of the Mahabharata War is the correct and proper sheet anchor to derive the chronology of Bharat since Mahabharata War. Mahabharata text of Veda Vyasa describes the positions of Graha (Planets, Star and Satellite) i.e. Sun, Moon, Jupiter, Saturn, Mars, Venus and Rahu and Ketu, the ascending and descending nodes of Moon and also the occurrence of Lunar eclipse followed by Solar eclipse at 13 days interval in the Karthika month.

Using the trigonometric mathematical i.e. sine and cos calculations, described in the ancient astronomical texts of Bharat, we can verify these astronomical events described in Mahabharata text and thus can derive the date of Mahabharata War correctly.

In this the mean positions of these Graha described in the astronomical text of Bharat, Graha Laghavam of Ganesa Daivanja at 1442 Salivahana Saka (1520 C.E.) on Chita first day of Sukla Paksha. These are described elaborately in this book and the date of the Mahabharata War is derived and shown to be at the 42nd year before Kaliyuga (3143 B.C.E.).