INDIAN LUNI-SOLAR ASTRONOMY where D' means the Moon as corrected by the 1st and the 2nd equations. Here the constant is wrong by -1' 18". 124 (4) His fourth equation or the annual equation = of the Sun's equation of apsis,¹ apogee). 1 10 X 12x3438 360 =t11'27". 6 sin (Sun's distance from the apogce). The modern value of the constant is 11' 10". Tycho found it to be 4' 30". Horrocks' (1639) co-efficient was 11' 51". sin (Sun's distance from the As Candrasekhara was aware of Bhaskara's Bijopanaya, as also of the work of Sripati, his merit here lies in the discovery of the annual equation, and correction to the constant of variation. Thus we have seen that so far as the luni-solar astronomy is concerned Indian astronomy is independent of Greek astronomy in respect of astronomical constants, that Indian astronomy is generally more accurate than Greek astronomy and that Indian astronomers were not mere "calculators". There were observers who verified and corrected the old astronomical constants as they came down from Aryabhata and Brahmagupta, who also found independently all the principal equations of the Moon. 1. Siddhanta darpana VI. 13. 2. G.R. Kaye Hindu Astronomy, p. 60 P.C. Sengupta
Karl Manitius's edition: Godfray
Reference The Khandakhadyaka, 1934 Syntaxis. Lunar Theory.