One of the remarkable aspects of Jai Singh’s observatories is that each site is distinctly different in size, layout, and style. While the instruments he designed are essentially the same in principle, the versions at different sites vary in size, materials, and construction.
The first observatory to be built was the observatory at Delhi in 1724. The Jaipur observatory, the most elaborate, was begun by 1728. Smaller observatories were built in Benares, Ujjain, and Mathura. Of the five observatories, all except the observatory at Mathura still exist and are publicly accessible. The Mathura observatory, and the fort in which it was housed, were demolished just before 1857.
The observatories at Delhi and Jaipur are the best known and most visited, since they are within major tourist destinations. They also feature the largest versions of the instruments Jai Singh built, and the Jaipur observatory houses the greatest number and variety of instruments.
The Jaipur observatory is by far the most elaborate and complete of Jai Singh’s projects, comprising sixteen masonry instruments and six made of metal. The observatory occupies a plot of land just outside the City Palace, within the walls of the original city.
The observatory includes a number of instruments that are not duplicated at the other sites. These include the Kappala Yantra, Rasivalaya Yantras, and Unnatamsha Yantra.
1929 Print - Indian Astronomy Observatory Landmark
Jantar Mantar, Jaipur
Rare Book Society of India
Ved Shala or Jantar Mantar in Ujjain is believed to be India’s first and foremost observatory. Indian astronomers believe that the first meridian or the Prime Meridian of Longitude (75° 47′ E) passes through Ujjain thus earning it the epithet, ‘Greenwich of India’.
The Tropic of Cancer also passes through Ujjain making it most suitable for an observatory. This observatory, made by Raja Jaisingh of Amer, is among the five built by him in India, the others situated at Delhi, Jaipur, Mathura and Varanasi.
The Jantar Mantar has all the constructional instruments which determine the positions of heavenly bodies in space. Nadivalaya Yantra, Yamyotarra – Bhitti Yantra, Shanku Yantra, Nadivalaya Yantra, Samrat Yantra and Sundial are the major instruments in the Ved Shala.
Although the Jantar Mantar in Ujjain is smaller than that of Delhi and Jaipur, this observatory is most important as the Masonic instruments are still being utilized to conduct research.
After Raja Jai Singh, the observatory remained isolated and poorly maintained for 200 years till it was renovated by Madhavrao Scindia. The Ved Shala is located on the Chintaman Road, 2.5 kms from Ujjain Railway Station and can be easily reached by local transport.