October 2023

Mathematical Matrix


Method for Finding  Star ( Nakshatra )

K Subramani
International Institute of Information Technology, Bangalore
Email : Subramani.k@iiitb.ac.in

We consider the problem of finding day, associated star and Zodiac sign, given just date. For example,  which day Mahatma Gandhiji was born? We know his date of birth is October 2nd 1869. Can we find star associated with date and also zodiac sign?

Given the understanding that a week consists of 7 days, number of days in a month and number of  months in a year and so on, this is just a problem of calculating the total number of days from a reference date whose day is known.

Conventional Methods

  1. Finding associated star for any date on Julian Calendar from 1-1-4713 BC to 4th October 1582 AD.

Step 1: Select any date. Calculate the total days from 1-1-4713 BC

Step 2 : Divide the total number of days from tropical period of Moon (27.321582 days)

Step 3: Take three digits, after the decimal point, of the result of Step 2 with decimal point and multiply

by 27.

Step 4: Add 9 or subtract -18 from the result.

Step 5: The result of Step 4 gives associated star for the given Julian Calendar Date.

Method for finding Approximate Hindu Nakshatra

A Method to find associated Star for Hindu calendar from 22-3-285 AD.

The date 22-3-285 AD is in Julian calendar. We calculate the total number of days from 22-3-285AD to end of Julian calendar date, 4-10-1582 AD. The number of days is 473925.

From 15-10-1582 to 31-12-1582 we calculate the remaining days to be 78 days.

Therefore, total number of days is, 473925+78 = 474003 days. Hereafter, from 1-1-1583 we follow  Hindu calendar and assume 1 year = 365.24218 days. For Hindu calendar, sidereal period of moon is  27.3216615.

Method of finding stars associated with a date on Hindu calendar:

If selected date is in Julian calendar we use 1 year = 365.25 days. For Gregorian calendar we use 1 year

= 365.24218 days.

Step 1: Calculate the total number of days from 22-3-285AD.

Step 2: Divide the total days from sidereal period of Moon (27.3216615 days).

Step 3: Take 3 digits after the decimal point with the decimal point and multiply by 27.

Step 4: This product gives stars associated with the date.

Example : Given date 4-4-1017. This date is the date of birth of Ramanujacharya. The day is known to be

Thursday and star associated with this date is Aridhra.

As per Julian calendar, the total number of days is 267376. Dividing by 27.3216615 we get 9786.22767.

Multiplying .227 by 27 we get 6.129 and the associated star is Aridhra


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