Certain Peculiarities of Jaina School of Astronomy

Summary

This article surveys the distinctive features of the Jaina astronomical system. Its purpose is to expose characteristics of a system built on Jain canonical literature and largely free of foreign influences. Unlike Greco‑Indian or Hindu astronomers, the Jains conceive of the universe as a vast, three‑tiered cosmos with a central island, Jambūdvīpa, surrounded by concentric continents and oceans. Mount Meru, a cosmic axis at the centre, anchors the heavens; the sun, moon and planets revolve around it in circular or semicircular orbits. Jaina cosmology divides time into infinitely repeating ascending and descending half‑cycles (utsarpiṇī and avasarpiṇī), each containing six ages of increasing or decreasing happiness. These immense cycles reflect the doctrine that the cosmos is eternal and cyclical. The article explains how Jaina astronomers developed their own units of measurement for time and space. They used conventional measures for mundane reckonings and scriptural units such as palyopama and sāgara to denote extraordinarily long durations. The Jaina year, divided into fortnights and months, was reckoned differently from the Hindu luni‑solar calendar, and Jaina texts describe elaborate formulas for calculating tithis and planetary positions. Unique to Jaina astronomy is the rejection of epicycles; instead, planetary anomalies were explained through differences in orbital speed and distance. The author highlights the Jaina belief that there are innumerable suns, moons and worlds in the middle universe (madhyaloka), though only our region is observable. Another peculiarity is the emphasis on moral cosmology: changes in the cosmic cycle are linked to the ethical state of beings and the prevalence of right conduct. By comparing Jaina astronomical treatises with Hindu and later Islamic works, the article shows that Jaina astronomers maintained a distinct intellectual tradition. Their models provided a framework for religious calendars and ritual observances, and they reinforced metaphysical doctrines of infinity, non‑absolutism and the indestructibility of the soul. The article concludes that Jaina astronomy deserves recognition not merely as a derivative tradition but as an independent and philosophically rich system.