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

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obtain the rising time of the planet p, which occured
before that of q, Vilōmalagna or an anterior point of time
is to be computed, and this is done by subtracting the asus
of Akṣa-Dṛk-karma from the rising time of q. The rest
follows on these lines of elucidation.
Verse 9. The planet rises at the time known as its
Udayalagna (which is to be computed as aforesaid) and
it sets at the time known as its Astalagna (which is also
to be computed as mentioned before).
Comm. Clear.
Verse. 10. During the night, at a given moment, the
computed Udayalagna of the planet is less than the
particular lagna of the moment, ie, if the longitude of the
Udayalagna is less than that of the current lagna, and
also if the Astalagna of the planet computed is greater
than that of the then current lagna ie. if the longitude of
the Astalagna is greater than that of the current lagna,
the planet is visible ie. above the horizon. In the case
of the Moon, however, if he is not eclipsed by the rays of
the Sun, he may be visible even shortly after Sunrise or a
little before Sunset in contradistinction to a planet which
could not be seen at all during day time (except perhaps
Venus). When a planet is visible, his gnomonic shadow
could be computed. (This does not mean that the gnomon
casts a shadow of the planet but means that its zenith-
distance could be computed according to the methods
described in Tripraśnādhikāra.
Comm. Clear.
Verse 11. To obtain the shadow, the time that has
elapsed after the rise of the planet is to be known.
If it be required to find the gnomonic shadow of the
planet, then the current lagna and the Udayalagna of the