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

451 Computing the latitude as indicated in the next verse, by the formula (H sin NSP × β × R) / (R × K) where β is the maximum latitude cited above in the respective cases, multiplied by R and divided by K indicates that the linear magnitude of the latitude will be increased or decreased according as K is smaller or greater than R. Fig. 105 Fig. 106 (a) In this context, we are to throw light on some moot points. Bhāskara says “मन्दस्फुटो ग्रहः स्वशीघ्र प्रतिमण्डले भ्रमति, तत्र च तस्य पातोऽपि”, which tantamounts to saying that the node is situated in the heliocentric orbit “स्वशीघ्र- तिमण्डल”. The Vimandala or the planet's orbit, taking for example the inner orbit of P in fig. 105, does not exactly lie in the plane of the ecliptic as shown in that figure but is in an inclined position cutting the coplanar inner orbit in N and N', as shown by the ellipse NPN' where NP = NP'. The argument to calculate the latitude is NP' and the formula is (H sin NP' / R) × β to give the helio- centric linear latitude. To obtain its geocentric linear value, we have to multiply by R / K.