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

68 by x°/10 + x°/88 + Dhruvaka as given by the verse. Verse 21. To obtain the position of the lunar Node Rahu. The Ahargaṇa multiplied by 30 and divided by 566 gives the number of degrees to be added to the Dhruvaka to give the position of Rahu. Comm. If the number of the sidereal revolutions of Rahu in a Kalpa multiplied by twelve divide the number of days in a Kalpa we have very approximately 566, which means that Rahu traverses a Rasi very nearly in 566 days. Hence dividing the Ahargaṇa by 566, and multiplying by 30, we have the degrees covered, which being added to the Dhruvaka gives the position of Rahu. Verses 22, 23, 24. Alternative method of obtaining the planetary positions. The Ahargaṇa multiplied by 100000, and divided successively by 101461, 151787, 190833, 24436, 1203400, 62416, 2990000, 898000, 1886800 gives the respective posi- tions of theplanets beginning from the Sun and those of the apogee and Node of the Moon; in the case of the Moon, however, the result is to be multiplied by 20. The results in degrees added to the Dhruvakas give their posi- tions. Comm. The degrees covered by the planets etc in D days are (R × 360 × D°) / M where R is the number of side- real revolutions in a Kalpa, M the number of mean solar days in a Kalpa, and D the Ahargaṇa. Now (R × 360 × D) / M = (R × 360 × D × 100000) / (M × 100000) = (D × 100000) / ((M × 100000) / (R × 360)) . Then (M × 100000) / (R × 360) is found for every planet. In the case