Sukumar Ranjan Das

The Jaina Calendar

By Sukumar Ranjan Das

The Jaina astronomers based their chronology on a five-year cycle known as the quinquennial yuga, which is identical to the cycle described in the Jyotisa-vedanga and in the Garga Samhita. According…

Notion of Time in Hindu Philosophy

By Sukumar Ranjan Das

In Hindu philosophy, time (Kala) is conceived as an all-powerful, independent reality governing motion, existence, and change. Early thinkers described time through vivid metaphors, like a horse with…

The Jaina School of Astronomy (Part II) - The Theory of the two Suns

By Sukumar Ranjan Das

The Jaina School of Astronomy

By Sukumar Ranjan Das

A Short Chronology of Indian Astronomy

By Sukumar Ranjan Das

Ancient Indian astronomy originated in the Vedic period (circa 1500–500 BCE), where celestial bodies were linked to deities and their motions observed to determine festivals and seasonal cycles.…

Seasons and the Year-Beginning of the Hindus

By Sukumar Ranjan Das

The Hindu system divides the year into six seasons (Ritu) based on the sun's annual motion and its impact on daylight duration and temperature. Astronomically, the sun's declination and right…

Hindu Calendar

By Sukumar Ranjan Das

The Hindu calendar evolved from early timekeeping tied to rituals and agricultural cycles, initially imperfect but later refined into complex systems. Core units include days, months, and years, with…

Astronomical Instruments of the Hindus

By Sukumar Ranjan Das

Drawing on Sanskrit treatises and historical observations, this article catalogues the principal instruments used by Indian astronomers from antiquity through the medieval period. It begins with the…

The Alleged Greek Influence on Hindu Astronomy

By Sukumar Ranjan Das

The debate over alleged Greek influence on Hindu astronomy centers on conflicting scholarly interpretations. Some European scholars, including Kaye and Smith, argue that post-Vedic Hindu astronomy…

Cosmographical Theories of the Hindu Astronomers

By Sukumar Ranjan Das

The Hindu astronomers' cosmographical theories, as detailed in the text, blend metaphysical and early scientific concepts. Central to their model is the primordial state of darkness, from which water…

The Origin and Development of Numerals

By Sukumar Ranjan Das

The decimal numeral system is so ubiquitous today that its complex history is often forgotten. This essay traces the evolution of numerals from ancient times to the adoption of the so‑called “Arabic”…

The Origin and Development of Numerals

By Sukumar Ranjan Das

The origin and development of numerals trace back to ancient Hindu practices, where early counting relied on finger positions to represent numbers up to 10,000. This system, later formalized into…

Aspects of the History of Hindu Astronomy

By Sukumar Ranjan Das

Focusing on the evolution of Indian astronomy, this article traces the development of astronomical ideas from Vedic ritual to the classical Siddhānta period. The author discusses how early Vedic…