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The planet's past position at the beginning of Ardra The 6th lunar mansion or Nakshatra is 2 signs, 6 degrees, and 50 minutes. The planet's future position at the beginning of Punarvasu The 7th lunar mansion is 2 signs, 12 degrees, 0 minutes, and 0 seconds. The difference between the two in degrees and minutes is 3 degrees and 20 minutes. Multiplying this by the elapsed desired time in nadis A unit of time equal to 24 minutes of 1077 and dividing by the total duration of the mansion in nadis of 1229, the resulting degrees and minutes are 6 degrees, 34 minutes, and 13 seconds. Adding this to the past planetary position of 2 signs, 6 degrees, and 40 minutes, the result is the True Mars: 2 signs, 11 degrees, 8 minutes, 11 seconds, and 13 thirds.
Where the multiplicand and the multiplier both contain fractions, the "cow's urine" method of multiplication Gomutrika-gunanam: a zig-zag method of multiplication used in ancient Indian mathematics for multi-digit or fractional numbers should be performed. Where the dividend and divisor both contain fractions, the rule is that the division should be carried out after reducing them to a common denominator.
Now, the daily motion: 480,000 seconds divided by the total mansion duration of 1229 nadis results in a motion of 38 minutes and 54 seconds.
In this case, Mercury is retrograde Appearing to move backward in the sky. Because of this, on the 8th lunar day, at 6 ghatikas and 54 palas, it became retrograde. Therefore, the desired elapsed time is 53 ghatikas and 6 palas. Between the day of retrogression and the current day, 5 days have passed; their duration is 300 ghatikas. The desired time is 8 ghatikas and 58 palas. The sum of these is the total elapsed time: 362 nadis and 4 palas. Because they are negligible, the palas seconds/sub-units of time are discarded.
Now, calculating the total duration of the mansion: the time on the day of retrogression was 53 ghatikas and 6 palas. From that day forward, at 45 ghatikas and 39 palas past the 60-mark, Mercury returned to the Krittika mansion The 3rd lunar mansion, the Pleiades; thus the time is 45 ghatikas and 39 palas. Between the days of retrogression, there are 12 days; their duration is 720 ghatikas. The sum of all these is 818 ghatikas and 45 palas, which is the total mansion duration.
Now for the planetary calculation: On the day the planet became retrograde, the position as calculated in the almanac was 1 sign, 18 degrees, 50 minutes, and 29 seconds. Moving in reverse each day from the day of retrogression, it eventually returns to Krittika, where the future position is 1 sign, 10 degrees, 0 minutes, and 0 seconds. The difference between the past and future positions in degrees and minutes is 8 degrees, 50 minutes, and 24 seconds. Multiplying by the elapsed time of 362, and converting by sixty, the result in three places is 3200, 54, and 40. Multiplying by sixty and adding the lower minutes, it becomes 19200, 54, and 40. Dividing this reduced value by the total mansion duration of 49125, the resulting degrees and minutes are 3 degrees, 54 minutes, and 30 seconds. Because it is retrograde, this is subtracted from the past position of 1 sign, 18 degrees, 50 minutes, and 24 seconds. The result is: True Mercury: 1 sign, 14 degrees, 55 minutes, and 54 seconds.
Now the daily motion: Due to retrogression, the difference in degrees is 8 degrees, 50 minutes, and 24 seconds. Multiplied by sixty, it is 53 minutes and 24 seconds. Reducing this, we get 31824. Dividing this by the total duration of 49...