Place · observatory · India
Ujjain observatory (Vedh Shala)
The Vedh Shala observatory built by Jai Singh II around 1725 at Ujjain, Madhya Pradesh — the fourth of his five observatories (after Delhi, Jaipur, Mathura; Varanasi came later). Jai Singh deliberately sited Ujjain on the Tropic of Cancer meridian — the zero-meridian of Indian astronomy for over a millennium — placing a new instrument on the inherited theory of Varahamihira and Brahmagupta who had worked at Ujjain in the 6th-7th centuries. The observatory holds thirteen main instruments including a Samrat Yantra sundial. Ujjain's longitude is 23.17°N, 75.78°E; the ancient Indian prime meridian ran through here before the Greenwich meridian was imposed in the 19th century.
- Function
- Science & medicine
- Confidence
- Established / referenced
- Location
- 23.179, 75.785
Connections (4)
- Architectural modelJantar Mantar, Delhi
Five observatories were built to one programme — Delhi, Jaipur, Ujjain, Mathura and Varanasi — with the same instrument types in different sizes, because Jai Singh wanted simultaneous observations from several longitudes. Ujjain's was put on the meridian Indian astronomers had used as their prime reference for a thousand years, so an eighteenth-century instrument was sited on inherited theory rather than on convenience.
- Astronomical alignmentUjjain / Avantikā
Sawai Jai Singh II built the Vedh Shala at Ujjain in the 1720s as one of his five jantar mantars, siting it on the meridian Indian astronomy had used as its zero longitude for over a millennium. Ujjain served as India's Greenwich for classical astronomical calculations from at least Varahamihira's time.
- Life routeBhāskara II
Bhāskara II headed the astronomical observatory at Ujjain, as Varāhamihira and Brahmagupta's tradition had before him, which makes the town the longest-running centre of mathematical astronomy in India. It sits on the meridian Indian astronomers took as prime, so longitudes across the subcontinent were reckoned from it for more than a thousand years before Greenwich existed.
- TransmissionSawai Jai Singh II
Jai Singh sent an embassy to Portugal that returned with European astronomical tables, had Euclid and Napier's logarithms translated into Sanskrit, and employed Hindu, Muslim and Jesuit astronomers together. He then compared their results against his own observations and found the European tables wanting. Siting one of the five observatories at Ujjain placed his instruments on the meridian Indian astronomy had used for fifteen centuries.
On these journeys
Sources
Vedh Shala records
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