सिद्धान्तशिरोमणि: गणिताध्याय (भास्कराचार्य - ग्रहगणित, मध्यमाधिकार व स्पष्टाधिकार सटीक)

214 but dividing the elongation by 6, we are asked to count K — 1, (where K is the quotient) beginning with Bava because the first half of Sukla pratipat is covered by the fixed Karaṇa Kimstughna. The computation of the elapsed as well as the remaining nādīkas of a particular Karaṇa, it proceeds on the same lines as that of a tithi. (5) The Nakṣatra in which a planet or the Moon is situated is then found. The zodiac is divided into 27 equal divisions beginning with its zero point and each division is named after the brilliant star of that division. Those stars are Aświnī, Bharaṇī etc. The star occupied by the Moon has a special significance in the Hindu calendar, it being spoken of that every day is presided over by a nakṣatra. This happens so because the Moon’s sidereal period is approximately 27 days. (6) To compute the Nakṣatra in which the planet or Moon is, take its longitude in minutes of arc λ; divide by 800, since each star division consists of 360° / 27 = (360 × 60) / 27 minutes = 800'. The quotient gives the elapsed nakṣa- tras. To get the elapsed nādikās of the current nakṣatra or the remaining, let the remainder be r'. Then the proportion is ‘If during the day of 60 nādīs, the planet or the Moon goes p minutes what time does it take to cover r' or 800 — r'’. The answer is (r' × 60) / p' or ((800 — r') × 60) / p' = गतैष्यविलिप्तिकाः / p' . (7) Regarding yogas, let the longitudes of the Sun and the Moon be ☉ and λ in minutes of arc; let their daily motions be s and m in minutes. If the sum of the longi- tudes is 800', we say the first yoga named Viṣkambha is over, if the sum is 1600', the second Yoga, named prīti has elapsed. Thus going on if the sum is 360°, we say the 27 yogas have elapsed and the first again begins. Since the sum of the daily motions of the Sun and the Moon