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

401 in the arc LM?" We get the magnitude of the arc AC in minutes. The computation of this arc AC is intended to know the difference between the times of rising of the point A and the point G the former being the point of the ecliptic signifying the position of the planet and the latter being the planet itself. This difference of the times of rising is itself required to know the actual time of rising of the planet by a knowledge of the time of rising of the point which signifies the planet’s position on the Ecliptic by its longitude. In verse 5, Bhāskara gives an alternate and easy method of obtaining the magnitude of AC construing AGC to be roughly a plane triangle which does not involve any appreciable error. AC = AG tan AĜC = (β × H sin AĜC) / (H cos AĜC) = (β × Āyanavalanajyā) / Yaṣṭi since Yaṣṭi is defined as H cos AGC in verse 3. Note. The point C is called the Kṛta-Āyana-Dṛk- Karma Sthāna ie. the point of the Ecliptic signifying the planetary position rectified for the Samskāra or correction called Āyana-Dṛk-karma. The longitude of C thus got is called the polar longitude of the planet which is defined as the longitude of the planet as measured on the Ecliptic upto the point of intersection of the planet’s declination circle with the Ecliptic. Bhāskara mentions elsewhere, “ नक्षत्राणां स्फुटा एव स्थिरत्वात् पठिताः शराः दृक्कर्मणाऽऽयनेनैषां संस्कृताश्च तथा ध्रुवाः ” ie. in the case of stars which are fixed, the Sphuta-saras or polar latitudes (given by GC in the above case) are