Astronomer King of Rajasthan- Jai Singh II

Sawai Jai Singh II, one of the greatest rulers of the Kachhawaha clan, is well known as ‘the astronomer king of Rajasthan’. The unique inventions designed by him are famous not only in India but all over the world. Jantar Mantar or the ‘Yantralaya’ of this astronomer king is the live example of his inventions. One can see the modernistic structures here that are known as ‘Yantras’. Sawai Jai Singh designed them to observe the movement of astronomical bodies.
Jai Singh exploded on the horizon of the Indian Astronomy. He tried to give the astronomy a new life by bringing new ideas from the west and thus arose a chain of magnificent observatories, which are famous as Jantar Mantar (Yantra Mandir). Jai Singh was passionate about astronomy and numerology since his childhood but his father died when he was only eleven. He continued his studies along with his princely duties and acquired mastery over subjects of astronomy and mathematics. He designed instruments, built observatories and compiled an excellent library.

He collected and studied all the available works of Indian, Arabic and Greek astronomers, and had some translated into Sanskrit. He also collected brass astrolabes, sextants and sundials to make his own observations. But as they failed to measure up to his exacting standards, he decided to build giant stone and masonry structures of his own design.

Thus, he created a collection of a mathematician’s paradise in the form of Jantar Mantar with the help of his skilled labourers, who chiseled out the complex astronomical instruments of stone. Even today these instruments could provide accurate information of the day and can be compared with modern instruments indisputably. These structures with their striking combination of geometric forms at a large scale have mesmerized the attention of architects, artists and art historians worldwide.

Initially Jantar Mantar was named as Yantra Mantra, which means instruments and formulas. But that name has changed to the recognized name due to the mispronunciation of the earlier name. Basically these were built to observe the movements of celestial bodies so as to measure the local time, ascertain the declination of sun, stars and other planets, determine celestial altitude and predict the eclipses accordingly. Jai Singh built five observatories at Jaipur, Ujjain, Delhi, Mathura and Varanasi between 1724 and 1735. Observatories at different places were built to reduce the errors introduced due to the limits of human vision. The fifth observatory at Mathura has disappeared now.

Jantar mantar at Jaipur is the largest, best-preserved and elaborate observatories of its time and has a remarkable collection of architectural astronomical instruments. It contains 13 stone instruments and three metal ones design by Jai Singh. The Jantar Mantar, the open-air observatory, has the Samrat Yantra, a gigantic sundial of about 90 feet, which attracts the maximum attention of the visitors. It has been designed to measure local time to an accuracy of about two seconds, the position of the sun and the other heavenly bodies with great precision. Its shadow is carefully plotted to tell the time of the day and the ‘Hindu Chhatri’, a small domed cupola, at the top is used to announce the eclipses and the arrival of the monsoon. The devices in most cases are huge structures to obtain the accuracy of readings; each instrument serves a particular function and gives an accurate reading.

Jantar Mantar is the only stone observatory in the world. Every year astronomers from all over India meet at the ‘Jaipur Observatory ‘to prepare the Yearly Panchang (Indian Almanac) with the help of its various instruments.
These instruments that are scientifically designed, set and given shaped that depicts the forte of Medieval Indian Astronomy. This feature makes it a special destination for tourism.