CONSTRAINING THE PERIOD OF THE ORIGIN OF THE INDIAN LUNAR MANSIONS

Indian Lunar Mansions, known as nakshatra, have been fundamental to Vedic calendrical systems. There have been some attempts to determine an epoch, when these asterisms were first defined, based on subjective interpretations of positions of cardinal points at the epoch of definition. However, these attempts have mostly had a limited scope of investigation. We attempt to address the question of epoch of definition using another approach. We assume that the choice of a particular principal star for each lunar mansion was the best possible choice for each corresponding ecliptic longitude zone and we employ precessional calculations to show for which periods in history this particular assumption holds true. Our analysis shows the period of designation of nakshatras to be around 2400 BCE. Visual analysis of sky plots around 2400 BCE further provides corroborating arguments in support of this date. The method is also useful in disambiguation of certain nakshatra definitions.