Aryabha?a II

(fl. between ca. a. d. 950 and 1100).

Of the personality of ?ryabha?a II, the author of the Mah?siddh?nta (or ?yasiddhänta), virtually nothing is known. His date can be established only by his alleged dependence on ?r?dhara who wrote after Mah?v?ra (fl. 850) and before Abhayadeva Süri (fl. 1050); and by his being referred to by Bh?skara II (b. 1114). He must be dated, then, between ca. 950 and 1100. Kaye’s strange theories about the two ?yabha?as, which would have placed ?ryabha?a II before al-B?r?n? (963-after 1048), have been refuted by Datta. Nothing further can be said of ?ryabha?a II; manuscripts of his work are found in Mah?r???ra, Gujarat, and Bengal.

The Mah?siddh?nta (see Essay VII) consists of eighteen chapters:

1. On the mean longitudes of the planets

2. On the mean longitudes of the planets according to the (otherwise unknown) Par??arasiddh?anta.

3. On the true longitudes of the planets.

4. On the three problems relating to diurnal motion.

5. On lunar eclipses.

6. On solar eclipses.

7. On the projection of eclipses and on the lunar crescent.

8–9. On the heliacal risings and settings of the planets.

10. On the conjunctions of the planets

11. On the conjunctions of the planets with the stars.

12. On the p?tas of the sun and moon. Chapters 13–18 form a separate section entitled Gol?dhy?ya (“On the Sphere”)

13. Questions on arithmetic, geography, and the mean longitudes of the planets.

14–15. On arithmetic and geometry.

16. On geography.

17. Shortcuts to finding the mean longitudes of the planets.

18. On algebra.

The Mah?siddh?nta was edited, with his own Sanskrit commentary, by MM. Sudha?kara Dvivedin, in Benares Sanskrit Series148–150 (Benares, 1910).

BIBLIOGRAPHY

Works dealing with ?ryabha?a II, listed chronologically, are F. Hall, “On the ?rya-Siddh?nta,” in Journal of the American Oriental Society, 6 (1860), 556–559; G. R. Kaye, “Two ?ryabha?as,” in Bibliotheca mathematica, 10 (1910), 289–292; J. F. Fleet, “The Katapayadi Notation of the Second Arya-Siddhanta,” in Journal of the Royal Asiatic Society (1912), 459–462; B . Datta, “Two ?ryabha?as of al-Biruni,” in Bulletin of the Calcutta Mathematical Society, 17 (1926), 59–74, and “?ryabha?a, the Author of the Ga?ita,” ibid., 18 (1927), 5–18; ?. B. D?k?ita, Bh?rat?ya Jyoti???stra (Poona, 1931; repr. from Poona, 1896), pp. 230–234.

David Pingree