पृष्ठम्:लघुभास्करीयम्.djvu/१५०

विकिस्रोतः तः
एतत् पृष्ठम् अपरिष्कृतम् अस्ति

77 VSS. 8-10] LAMBANA from the longitude of the meridian ecliptic point while finding the madhyajya; whereas they would have been for the Moon, had the author, while calculat- ing the value of the drkksepajya, also taken into account the celestial latitude due to the rising point of the ecliptic (more correctly, the rising point of the Moon's orbit). See MBh, v. 1 3-23. The intention of the author seems to find such values of the drkskepajya and drggatijya as may roughly correspond to both the Sun and the Moon. The artifice adopted for the purpose by him, however, is not mathematically correct. It would have been better if he had omitted the use of the celestial latitude calculated from the longitude of the meridian-ecliptic point. See Paramesvara's commentary on LBh, v. 1 1-12. A rule relating to the determination of the lambana-nadh for the time of apparent conjunction of the Sun and the Moon: 8-10. Having divided the square root thereof by 191, further divide the quotient by 4 and a half: the result m nadh is the time known as lambana in the case of a solar eclipse. It is subtracted from the time of (geocentric) conjunction if the latter occurs in the forenoon, and is added to that if that occurs in the afternoon. To get the nearest approximation for the lambana {i.e., the lambana for the time of apparent conjunction of the Sun and Moon), one should similarly perform the above operation again and again with the help of the time of (geocentric) con- junction. The term lambana means the difference between the parallaxes in longi- tude of the Sun and Moon. The above rule aims at finding the lambana in terms of time, for the time of apparent conjunction (in longitude) of the Sun and Moon. Buta ? f thlS lambana depends on the time of apparent conjunction of the Sun and Moon itself, which is unknown, so recourse is taken to the method of successive approximations prescribed in the text. To begin with, the time of geocentric conjunction of the Sun and Moon is taken as the first approximation to the time of apparent conjunction, and The Moon's drkksepajya is the Rsine of the zenith distance of that point of the Moon's orbit which is at the shortest distance from the zenith; and the Moon's drggatijya is the distance of the zenith from the plane of the secon- dary to the Moon's orbit passing through the Moon.