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

435 The apparent latitude of the Moon is equal to the algebraic sum of his geocentric latitude and the parallax in latitude. From this apparent latitude are to be calcu- lated the Sthiti-khanda and Marda-khanda of the solar eclipse (by the method described in the chapter on lunar eclipse, taking the eclipsing body or grāhaka to be the Moon and the eclipsed or Grāhya to be the Sun). Comm. The geocentric parallax of the Moon has a double effect on the occurence of a solar eclipse as men- tioned before. If the parallax be resolved along the Ecliptic and along a secondary to the Ecliptic, we have respectively the parallax in longitude and that in latitude. The parallax in longitude makes the apparent moment of conjunction at a given place, differ from the moment of the geocentric conjunction, whereas the parallax in latitude makes the magnitude of apparent latitude of the Moon at the place of observation differ from that of the geocentric. The apparent latitude is equal to the sum or difference of the geocentric latitude and the parallax in latitude. Having got the apparent latitude, the computation of the Sthiti and Marda-khandas could be done according to the method described in the chapter on lunar eclipse. For a point C on the surface of the Earth, a solar eclipse occurs if the latitude of the Moon be less than MD Fig. 100