पञ्चसिद्धान्तिका (आचार्य वराहमिहिर - सूर्य, रोमक, पौलिश, वासिष्ठ एवं पितामह सिद्धान्त)

XVIII.58 XVIII. VĀSIṢṬHA-PAULIŚA – RISING AND SETTING 351
[दृकर्म—आक्षम्]
ज्याविधिविक्षेपघ्ना (च्च) रकाला‘म्बराष्टवेदां’शम् |
जह्यात् क्षिपेच्च याम्योत्त(रे) ग्रहे खं यथा(काष्ठम्) || ५७ ||
एवं कृते [ग्रहान्त]रांशकैरस्तदर्शनं तेषाम् |
Correction for mean elongation in heliacal rising
57. Find the R sine of the latitude of the body. Multiply the (maximum) half-
cara (i.e. the half difference between the half day-time or night-time from 15
(nāḍis.) in vināḍis, by this R sine, and divide by 480. Add this or subtract this
(to or from the Moon or star-planet) if the latitude is north or south, according
to the proper direction, (i.e. according as the phenomenon of setting or rising,
takes place in the west or east, respectively).
58a-b. When this is done, their setting or rising happens according to the
interval in degrees (between the Sun, and the planet given in XVII.12, or the
Moon).
Note 1. There is a lot of lacunae in verse 57. The half-cara-vināḍīs meant is the maximum for the
place. yathākakṣam is meaningless here and is corrected into yathākāṣṭham, i.e. according to the direc-
tion, but the direction is not mentioned. If north latitude, the addition is for the Moon or planet in
the west. Also if north latitude, the subtraction from the Moon or star planet is to be done for the
east. If south latitude, the subtraction is for the west, and the addition for the east. These things can
be got by a little reflection.
Note 2. The amount of degrees to be applied can simply be got by multiplying the degrees of
latitude of the body by the tangent of the latitude of the place. (The equinoctial mid-day shadow
of the 12" gnomon ÷ 12, is tan. latitude of a place). The amount got is very rough.
The degrees wanted = Sin. half cara (i.e., tan latitude of place x tan. declination of the Sun) ×
sin (90° – angle for heliacal rising), nearly. The last term is neglected here, tan declination is
roughly taken as 48', half-cara is converted into degrees by division by 10, and the conversion into
sine-function is applied to the latitude of the planet instead of the half-cara, as roughly equal.
Note 3. This application is what is technically called Ākṣa-dṛkkarma. The Āyana-dṛkkarma is
neglected.
Note 4. The heliacal rising of the Moon, and of Venus and Mercury when retrograde, takes place
in the west. The heliacal setting of the Moon and retrograde Venus and retrograde Mercury takes
place in the east. Otherwise, all star-planets set in the west and rise in the east. (This Siddhānta does
not envisage the setting or rising of Venus and Mercury when retrograde, no separate degree for
that being given).
57a. B1.3. ज्याविधिविधि d. A. ०्तरं; B. ०तंर०. C. स्वे. D. [कक्ष्यम्]
b. A.B. च for च्च A. ०दंबराष्ट; B. चरकादि 58a-b. A.B.C.D. ग्रहार्कन्तरांशकैः
(B2. कालादि) चराष्टवेदांशं B. ०तिष्ठतितिथ०
c. A. जह्याक्षि. A. यान्मो
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