ब्राह्मस्फुटसिद्धान्त (ब्रह्मगुप्त - शून्य, कुट्टक, बीजगणित एवं सम्पूर्ण २१ अध्याय सान्वय सटीक)

civil days in a Mahāyuga according to Brahmagupta as referred
to in the Khaṇḍakhādyaka.
Again, the same stanza tells us to subtract 20 and 4 respec-
tively from the revolutions of Mercury and Jupiter, and we arrive
at the figures 17,937,000 and 364, 220, which are the revolutions
of Mercury and Jupiter in a Mahāyuga according to Brahma-
gupta as given in the Khaṇḍakhādyaka.
Again we can compare the figures for the diameters of
the Earth, the Sun and the Moon given in the Mahābhāskarīya,
in the present day Sūrya-siddhānta and the Āryabhaṭīya.
Diameter Mahābhāskarīya Modern. Āryabhaṭīya
of Sūrya-siddhānta
Earth 1,600 yojanas 1,600 yojanas 1,050, yojanas
Sun 6,480 6,500 4,410
Moon 480 480 315
Then in stanza 24, we are given the distances of the Sun and
the Moon as 689, 358 and 51, 566 yojanas respectively. The
same figures are worked out by Lalla according to the
Āryabhaṭīya and quoted in the Śiṣyadhwṛddhida (IV.3.4) and they
come to be 459,585 and 34,377.
The stanza 25 states the longitudes of the aphelia of planets
these figures tally with the corresponding figures given by Brah-
magupta in the Khaṇḍakhādyaka :
Longitude of aphelion of Jupiter 160°, of Venus 80°, of
Saturn 240°, of Mars 110° and of Mercury 220°.
Similarly the stanza 26 gives the peripheries of planets’
epicycle of apsis, which also is in concordance with the values
given by Brahmagupta :
Periphery of epicycle of apsis of Jupiter 32°, of Venus
14°, of Saturn 60°, of Mars 70° and of Merury 28°.
In the stanza 27 of the Mahābhāskarīya, we have the
dimensions of the epicycles of conjunction for planets; these
figures are also the same as given by Brahmagupta :
Epicycles of conjuction for Jupiter 72°, for Venus 260°,
for Saturn 40°, for Mars 234° and for Mercury 132°.
In the stanza 28, we have the Sun’s epicycle having a
periphery of 14° and the Moon’s epicycle 31° ; the longitudes of