Location: One of the five observatories, i.e. Jantar Mantar, is situated at Parliament Street in Connaught Place of New Delhi. It incorporates 13 unique architectural astronomy structures.

Foundation year: From 1724 onwards

Year of completion: 1867

Founded by: Maharaja Jai Singh II of Jaipur

Structure: Obeying the orders of Mughal emperor Muhammad Shah, the king of Jaipur Maharaja Jai Singh made his dream-project in real terms. The structures of Jantar Mantar were built for creating such monument from where the position and direction of stars, heavenly bodies, as the sun and moon, could be observed easily. This way, the revision of calendar and astronomical tables could be done to predict the time and movements of the heavenly bodies.

The structure of Mantar Mantar is constructed in such geometrical format that resemble original and unique. Each striking geometrical structure would serve specialized function that meets astronomical purposes.

A brass vessel (plaque) is fixed at one end of this observatory that was placed in 1910. Due to some errors, its date was mistakenly declared 1710 but the research carried on in later years revealed its actual date of construction, i.e. 1724.

Significance of each structure: The popular term of now a-days, i.e. ‘Astronomy’ was the familiar concept at that time. But the fascination has not reduced a bit for modern architects, artists and art historians worldwide.

The observatory of Jantar Mantar has resemblance of the Great Sphinx of Egypt. The laid below listed Yantras or instruments were utilized for predicting the date and time near to absolute at that time:

  • Samrat Yantra: It is the principal Instrument, which appears a huge triangle that actually is an equal hour sundial. Its height is 70 feet that is 114 feet long at the base and its thickness is10 feet. Its 128 foot-long hypotenuse is built parallel to the earth’s axis whose pointing is towards the North Pole. On both ends of it has a quadrant with extensions displaying hours, minutes and seconds respectively. The construction of this Yantra made the sundial a meticulous device for concluding declination and other relevant coordinates of various planetary bodies.       
  • Jayaprakash Yantra: This Yantra appears with removed interior of its hemispherical structure including marks on their concave faces. Wires are stretched in criss-cross between the points marked on their rim. An astrologer or observer could anticipate the aligning position of a star from the mid, i.e. Ram.
  • Misra Yantra: This Yantra enables the observer to find out the shortest and longest days of the year along with the exact estimation of noon in various places irrespective of their distance from Delhi. The most amazing fact of it is that the exact estimation of noon in various cities of the world could be done via this yantra. It is the only yantra that was not built by Jai Singh II.

Similar Observatories: The credit of building five observatories in west-central India goes to Maharaja Jai Singh II those became famous as Jantar Mantar. The places for other four observatories were chosen as Jaipur, Ujjain, Mathura and Varanasi as they were the prime locations from where the estimations regarding astrology and astronomy could be made. These outstanding and exquisite monuments are the legacy and integral part of Indian heritage, which passed to us the lesson of astrology and astronomy.