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

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real period equal to the heliocentric sidereal period which
again means that the geocentric longitude of the Uccha is
the heliocentric longitude of the Planet. Thus the radius
vector to the planet from the Sun is parallel to the geocen-
tric radius vector of the Uccha. This accounts as to how
the heliocentric sidereal periods of Mercury and Venus
could be found under a geocentric concept and also as to
how the heliocentric planets are themselves spoken of
as their respective Ucchas, while their mean planet is the
same as the Sun. On this count it was mentioned by the
Hindu Astronomers ज्ञशुक्रयोः ग्रहः सूर्यो भवेत् तौ शीघ्रनाकौ ie.
The mean Planet of Mercury and Venus is the Sun himself
where as they are themselves spoken of as their Ucchas.
The phrase 'they are themselves' in the above statement
is significant as it connotes that the word 'they' stands for
the heliocentric planets, though it was uot stated in so
many words. Shortly we shall see also that the centre of
the eccentric circle coincides with the centre of the Sun
also and applying Bhāskara's statement 'यस्मिन्वृत्ते भ्रमति
खचरो नाऽस्य मध्यं कुमध्ये' i.e. the centre of the circle in
which the planet moves does not coincide with that of
the Earth', the Sun was, though unwittingly taken as the
centre of the Planetary motion. Thus we see how even
the geocentric postulation also could help computation of
the Planetary positions, the mathematics behind revealing
heliocentric motion. What Copernicus achieved was that
he identified that the point about which the planets revol-
ved which was construed by the Hindu astronomers as an
imaginary point not coinciding with the earth's centre,
was no other than the Sun himself.
In the case of Mercury and Venus the so-called
Sīghra-phala came to be discovered first and we shall pre-
sently see why their elongation was called Sīghra-phala
and how the Uccha postulated as above came to be termed
Sīghroccha. Since initially the equation was to be zero,
when the Planet and the Uccha coincided with the Sun