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

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four Ācāryas. Mādhava's statement in his Siddhānta
Cūdāmaṇi is as follows which is also in similar terms as
those of the other three.
रवेरोजपदक्रान्तेः चन्द्रयुग्मपदोद्भवा
स्वल्पाचेन्नतयोःक्रान्त्योः साम्यं स्यादन्यथा भवेत्
Verses 15 and 16. To obtain the duration of the
pāta.
The semi-sum of the diameters of the Sun and the
Moon or what is the same the sum of their angular radii
being multiplied by the Spaṣṭaghaṭis (obtained in the
estimate as per the verses 11-14) and divided by the Ādya
in that context, gives the beginning and end of the pāta
from the moment of the computed time. The process
being repeated according to the method of successive
approximations we have the correct estimate of the
duration of the pāta.
Comm. This is a convention stipulated with respect
to the duration of the Pāta. Strictly speaking, when the
diurnal paths of the centres of the discs coincide in the
case of Vyatīpāta, that will be the middle moment of the
Vyatīpāta. The pāta is said to last for such a time as the
distance between the Centres of the discs (north-south
distance) is less than r + p. This will be clear from a
figure. The situation is akin to that of an eclipse.
The time obtained for the occurrence of the pāta
under verses (11) to (14) indicates the middle of the
duration of the pāta. The duration of the pāta is defined
as the time that lasts as long as the declination of the
highest point of one disc becomes equal to that of the
lowest point of the other beginning from the moment at
which the declination of the lowest point of the one
becomes equal to that of the highest point of the second.
In other words, just like in an eclipse, so long as the
distance between the diurnal paths traced by the centres