Various observatories built by Raja Sawai Jaisingh II narrate the achievements and continued excellence of ancient Indian astronomy
A historic wonder stands in the Ujjain city and that is—the observatory. Raja Sawai Jaisingh II of Amer in Rajasthan built this observatory in 1733 CE. He was the Subedaar of Malawa then. Raja Jaisingh built observatories in Delhi, Varanasi, Mathura and Jaipur also. The first observatory he built was in Delhi, in 1724 CE. After constructing it, he analysed the statistics from it and when he found it correct, he built other four observatories.
This man, Sawai Jaisingh, was an expert in astronomy. He was fluent in Sanskrit. In addition, he had acquired knowledge of Arabic and Persian also in the company of Moguls. Interestingly, he also knew good amount of Marathi. Most of his time was spent in Aurangabad, Daulatabad, Ahmednagar etc.
The credit for making Sawai Jaisingh an exponent in astronomy goes to a Maharashtrian—Pandit Jagannath Samrat. Even though Samrat (Emperor) was part of his name, he was just a Brahmin appointed to teach Vedas to Sawai Jaisingh. However, this Jagannath Pandit was deep in the study of astronomy. He wrote the book Siddhant Kaustubh and even translated Euclid’s Geometry textbook. The Elements, from Arabic to Sanskrit.
Sawai Jaisingh never used metal while constructing the observatory under the leadership of Samrat Jagannath. European scientists used metal instruments and since metals expand/contract according to temperature, the measurements are quite wrong many a times. But in all five observatories built by Sawai Jaisingh, all instruments have been built with the help of stones carved in particular size and limestone only.
Unfortunately, only two of the five observatories—at Ujjain and Jaipur—are in functional state today. The observatory at Mathura has been destroyed, while the one at Varanasi stands in a very dilapidated state. The observatory at Ujjain consists of Samrat Yantra, Nadi Valay Yantra, Digansh Yantra, Bhitti Yantra and Shanku Yantra. The period of construction of this observatory is prior to the entry of Marathas into Malawa. Later, Shinde (Scindias) of Gwallior repaired it in 1925.
What is the significance of observatory at Ujjain among the five ones built by Sawai Jaisingh? Earlier, up to 400 BC, it was believed that the deshantar rekha (middle line) of the earth passes Ujjain. Besides, as Cancer passes through Ujjain, the town occupies a significant place in the Indian astronomy.
Washim in Maharashtra in olden times where Madhyameshwar temple is located, it is believed that the deshantar line imagined in ancient times passed through the shivalinga of Madhyameshwar. Interestingly, when Washim and Ujjain are seen in the earth’s elliptical fashion, they fall in the same line. Bhaskaracharya has referred to this deshantar line in his treatise Leelavati. The reference says that this imagined deshantar line passes through Ujjain (the book mentions Ujjain by its ancient name Avanti) and Rohatak, which is in Haryana today.
Long History of Ancient Astronomy
This ancient observatory is a slightly opened door to our ancient astronomical knowledge. This observatory has established nothing new, but it gives a glimpse to the books on which it was built and leaves us amazed.
The oldest references to our astronomy are found in the book Vedang Jyotish by Lagadh Rushi. Even though its title has Jyotish in it, it actually dwells on astronomy. Lagadh Rushi’s period is assumed to be 1350 BCE. The book prescribes the unit of ‘one month as 30 days’. It means the Indians had a deep knowledge of astronomy even 3300 years ago. perhaps even before that because Lagadh Rushi’s book never says about having found anything new. It means the book just put in words whatever knowledge of astronomy was available in the past.
Unfortunately, many of the ancient Indian texts are not available today. Many important books were destroyed during the time of Muslim invasion. Even the books that survived the onslaught were taken away by European researchers during the British rule.
One of these books is on Nardiya Siddhant dealing with astronomy. It is not available in India, but found in the museum of ancient books in Berlin as Narad Samhita (Webar Catalogue no. 862). Also, a rare book on astronomy on Soma-Chandra Siddhant which is part of Dharmtara Purana is also available in this museum (Webar Catalogue no. 840). Vashishta Siddhant is considered important in the ancient astronomy. The book, detailing the theoram similar to Surya Siddhant, is not available in India. But references to this book are found at many places in the book by astronomy experts Cottambrooks and Bentley (John Bentley —1750-1824). The Mathematical compositions of India astronomy expert Vishnu Chandra are based on this Vashishta Siddhant and Aryabhatta’s book. When searched as how Cottambrooks and Bentley found references to this book, when it was not available, one has found that this book was found at the 121st number in the Wilson catalogue of Mackenzy collection.
Bentley has written two research books on Aryabhatta’s works. First is Arya Siddhant and second is Laghu Arya Siddhant. Bentley liberally quotes two books by 5th century Aryabhatta—‘Arya Ashtaka Shatah’ (that has 800 shlokas) and Dash Gitika (ten sargas). Both these rare books are available at Webar catalogue no. 834 in the Berlin library!
The westerners have carried out much research on our Hindu astronomy. In 1790, Scottish Mathematician John Playfair strongly said, based on the information of Hindu panchanga (which reached Europe during the period of 1687 to 1787) that the starting point of Hindu calendar (or the point that can be reached through available books and calculations) was 4300 BCE.
One is just amazed to see and read all this. Many researchers of the oriental astronomy are of the opinion that going by the calendar in Indian books; one may get information up to 11000 years BC. This means our forefathers had the knowledge of space 13 thousand years ago or even before that. Then the original question remains there—from where did this modern knowledge come to our ancestors thousands of years ago?