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

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Formula for Sīghraphala from the heliocentric figures
In fig. 11, r / K = sin SÊV / sin EŜV so that sin SÊV =
r / K × sin m
In fig. 12 r / K = sin SĴE / sin EŜJ so that sin SĴE = r / K sin m
Both these accord with the Hindu formula.
It will be interesting to point out here that in fig 11,
keeping the earth constant and supposing the Sun S to go
in a circle with centre E and radius ES, the orbit of the
Inferior planet V will play the part of the epicycle of
Hindu Astronomy. Thus in the case of the Inferior planets,
the epicyclic theory is only a different version of the helio-
centric theory. In the case of the Superior planets, how-
ever, (fig. 12) cut off EJ¹=SJ along EJ" parallel to SJ; then
J¹J will be parallel to ES just as M₁M₂ is parallel to E₁E₂ in
fig. 13. Then the circle with E as centre and EJ¹ as radius
corresponds to the deferent of fig 13, whereas the circle (J¹)
with centre J¹ and radius J¹J corresponds to the epicycle.
The circle with S as centre and radius SJ corresponds to
the eccentric.
Verse 30. The equation of centre pertaining to the
Sun and the Moon using a simpler table of H sines where
the radius = 120 units. The H sines of the mean anomaly
as found from the simpler H sine table where radius = 120,
multiplied by 20, and divided by 1103 and 477 respectively
gives the equation of centre of the Sun and the Moon in
degrees.
Comm. The maximum equation of centre with respect
to the Sun is 2°-10'-31". Then the argument is "If by the
H sine of the anomaly equal to the radius 120, we have the
above max. equation what shall we have for H sin m?".