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

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rees covered in the next Rasi; proceeding thus, the planetary
position could be had next in minutes and then in seconds
of arc also. This position is the mean position of the
planet, at the time when the mean Sun is very nearly at
the Eastern horizon at Lanka. Why it is said "very
nearly at the horizon" will be clear in the context of uda-
yāntara Samskāra to be dealt with later in Spaṣṭādhikāra.
To obtain the planetary position at the moment when the
mean Sun is exactly on the horizon, we have to apply what
is called the Udayāntara correction and again to obtain the
position at the moment of True Sun-rise we have to apply
what is called the Bhujāntara correction, both of which will
be dealt with in Spaṣṭādhikara. Having thus got the
mean planetary position at True Sun-rise, we have to apply
one or two as the case may be, corrections to obtain the
True planetary position, besides effecting two more correc-
tions known as Desāntara and chara to obtain the True
planetary position at the time of True Sun-rise not at
Lanka but at the place concerned.
Verse 5. To obtain the position of the mean Moon,
when the mean Sun is known from what is called Avama-
Seṣa.
The Avama Seṣa divided by 131490000000 in degrees
is to be added to twelve times the elapsed tithis and the
result added to the Sun's position gives the position of the
Moon. Conversely the position of the Sun can be had from
the position of the Moon.
Comm. The moon's longitude minus the Sun's longi-
tude known as elongation is called Vyarkēndu, which
divided by twelve gives the number of elapsed tithis; a
lunation which is the time in which the Moon overtakes
the Sun by 360°, contains thirty tithis and a tithi is defined
as the time, in which the Moon overtakes the Sun by 12°,
beginning from the moment of conjunction ie Amāvāsyā.
Hence if the Sun's longitude be x°, aud y be the number of