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

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the celestial body, depression might have been noticed
during the course of an eclipse wherein conjunction or
opposition had to be belated; or again the greater equation
of centre as was postulated for the Sun, than what it
should be when his equation of centre was negative might
have depressed the Sun, so that the Moon had to be
depressed to arrive at the correct moment of conjunction
or opposition. Thus this correction of Natakarma which
was accepted by Bhāskara on the reported Āgama of
Brahmagupta and also on the right endorsement of
Chaturveda, must have been in fact no other than the
effect of the phenomenon of astronomical refraction, and
what further strengthens this observation is the prescri-
ption of H sin Z which is proportional tan Z. Also the
modern formula being A tan Z where A = 58″ approxi-
mately, when Z is sufficiently large, the magnitudes given
by Brahmagupta are of the same order as that of the
moderns. This correction of Natakarma really reflects
much credit on the ancient Hindu observations.
Verse 70. Computing the planetary position for a
given moment.
The daily motion of the planet being multiplied by
the time that has elapsed or that is to elapse at which
the planetary position is to be found, and divided by 60,
and the result being substracted from or added to the
planetary position found, will render the position hold
good for the moment in question. The Sun and the Moon
will become by this process of what is called तात्कालिकीकरण
equal up to minutes for the moment of conjunction or
opposition. For opposition only the Rāśis differ whereas
the degrees, minutes and seconds in their positions will
be equal whereas for opposition, the positions are equal
in all respects ie. Rāśis, degrees, minutes and seconds
too.
Comm. The meaning is clear.