JANTAR MANTAR - JAIPUR
Jantar Mantar is a collection of architectural astronomical instruments, built by Maharaj Jai Singh-II at Jaipur between 1727 and 1734. Maharaja Jai Singh-II had built five observatories in Delhi, Jaipur, Varanasi, Ujjain and Mathura. These observatories are indicative of its founder's passion and knowledge of astronomy and his scientific genius. As in medieval age, the kings used to believe in good and bad omens, auspicious and in-auspicious times etc in order to initiate any project or to set out on an expedition. During Mughal Emperor Muhammad Shah's regime, Muslim and Hindu astrologers got embroiled into a brawl because of their differences on various planetary positions. In order to avoid this kind of embarrassment, Sawai Jai Singh built Jantar Mantar in Delhi. Sawai Jai Singh's lofty ideal to enthuse renaissance in practical astronomy in medieval India remained unfulfilled as India at that time was passing through phase of turmoil.
These observatories are influenced by Ulugh Beg's observatory in Samarkand and overseen during construction by Xavier de Silva, the court astronomer of Portugal. In fact, Jai Singh's initial attempts to use brass instruments in the observatory didn't yield the desired results and precision owing to several inherent deficiencies in brass instruments. This led the astronomer king to look out for other practical options which he found in Samarkand observatory.
These astrological observatories were built to watch the movements of the celestial bodies like Sun, Moon, planets and stars. The term Jantar Mantar has been derived from Sanskrit words Yantra (physical instruments) and Mantra (formulae). These have been inscribed on the World Heritage List. The Jantar Mantar in Jaipur is the most elaborate one and is still operational. Not only a timekeeper of celestial bodies, these observatories are testimony of the the technological achievements made under the Rajput kings. There are 14 yantras (geometrical instruments) for calculating time, forecasting weather related changes, predicting positions of stars and planets and on the basis of that determining the future natural happenings. The Samrat Yantra- Prince of Dials (to measure accurate time), the Ram Yantra (to measure altitude of stars), the Jai Prakash (to display the sun's position at the time of eqinox), Mishra Yantra etc are prominent instruments. Each is a fixed and focused tool. The Samrat Yantra, the largest instrument is 90 feet high, its shadow carefully plotted to tell the time of the day.