Jantar Mantar Observatory, Jaipur

Stars and planetary movements have always been a subject of mysticism. A good number of people rely on them for accurate prediction of their life events. Before we had computers, Indian scholars had already devised methods to track planetary movements, predict the eclipses, star alignments, and future happenings. Well, the study not only amused the common, but it also fascinated the blue-blooded imperials too.

No wonder then that Maharaja Jai Singh II consulted astrologers before taking important decisions, and predicting his fate in wars. The Maharaja got inspired to build Jantar Mantar - an astronomical observatory located in the heart of Jaipur city. The idea was to enrich the Islamic Zij tables, to create an exact calendar, being able to measure precise time and make accurate predictions based on time. The Maharaja was interested in the subject that he had mastered Hindu astronomy and had read several books enhancing his knowledge about European, Persian and Islamic ways of astronomical studies. There are in total five such massive observatories constructed in the cities of Jaipur, New Delhi, Ujjain, Varanasi, and Mathura. Mathura’s observatory is in ruins now however, rest all are so preserved that they are running to date.

The Jantar Mantar Observatory in Jaipur is a set of 19 instruments meant for observing the celestial movements. The observatory was completed in 1734. One of the largest observatories in the world, Jantar Mantar, Jaipur can accurately predict Earth's orbit around the Sun, predicting eclipses and other astronomical activities. Being a UNESCO World Heritage site and National monument of Rajasthan, it attracts the interests of many architects, historians, astronomers, mathematicians, students and photographers from across the globe. The observatory has the largest stone sundial in the world at 73 feet tall and allows one to observe celestial positions from the naked eye.

Jantar Mantar Observatory, Jaipur
Predict Earth's Orbit around the Sun


Once in the observatory, there are a lot of activities to keep you glued and craving for more. The Yantras- as the instruments are called in Hindi – are some of the biggest and attract awe.

Jaipur Sundial: Also, called Vrihat Samrat Yantra, - meaning ‘great king of instruments’ - is a sundial designed to give local time to the precision of 2 seconds. The Sundial is the largest ever built. So big that its Gnomon arm is 22.6 meters high and quadrants are of the 15.5-meter radius. Interestingly the calibration done to read local time is through a triangle-shaped wall, standing in North-South Direction. Time is measured by the shadow casted by the wall as per the movement of sunlight. Perfect divisions between hours and seconds are made to read the time accurately. A correction factor is to be added to convert time readings into clock time readings.

Unnatamsa: Measures altitude of celestial bodies, with the help of a metal ring divided into four by horizontally and vertically placed metal rods, and a hole in the center.

Rasivalaya (Zodiacal Circle): Rasivalaya are instruments for predicting the celestial latitude and longitude and movement of astronomical bodies to understand zodiac signs. Twelve signs of the zodiac are represented by twelve instruments. Each one tracks the zodiac transit.

Laghu Samrat Yantra: This is also a sundial but smaller than the Vrihat Samrat Yantra. Inclined at 27 degrees it is less accurate and tells time to the precision of 20 seconds.

Jai Prakash Yantra: This is made up of two hemispherical bowl-shaped sundials. The marble slabs are marked and can map the inverted image of the sky for measuring altitudes, azimuths, declinations, and hour angles. To step up learning and fun the observer can move inside.  

Jantar Mantar Observatory, Jaipur
Laghu Samrat Yantra

Jai Prakash Yantra
Jai Prakash Yantra


Nadi Valaya: Nadi Valaya has two sundials on both faces of the instrument, representing north and south hemispheres. The instrument works to the accuracy of less than a minute.

Chakra Yantra: The instrument is instrumental in giving Sun’s declination through a Gnomon casted on four semicircular arcs. The Gnomon casts a shadow on four specified times a day. This is like measuring local times in different times of the world.

Digamsa (Azimuth): To measure the azimuth of the Sun, a pillar was erected in the middle of two concentric outer circles. This arrangement was also used to calculate and forecast time for sunrise and sunset.

Dakshin Bhitti Yantra: The instrument (yantra) is used for measuring meridian, altitude and zenith distances of celestial bodies.

Ram Yantra: Ram Yantra is an instrument with double cylinders used for measuring azimuth and altitudes of astronomical bodies.

Kranti writta: This Yantra measures the longitudes and latitudes of the celestial bodies.

Yantra Raj Yantra: The instrument to measure celestial movements and time is adapted from an astrolabe, a medieval instrument that was used to calculate astronomical measurements, like calculating latitudes for navigation, and altitudes of celestial bodies. The bronze astrolabe is one of the worlds’ largest, and calculates Hindu calendar.

Chakra Yantra
Chakra Yantra
Yantra Raj Yantra
Yantra Raj Yantra can calculate Hindu calendar


Shastansh Yantra: Used to measure the Sun’s diameter, zenith distance, and declination, this is a 60-degree arc built in Meridian plane, and having a dark chamber. Sunlight through pinhole falls on a scale, from which the measurements are done.

Jantar Mantar Observatory Timings: 9 AM to 4:30 PM (Open all days of the week)
Interest: Astronomy, History
Tickets: Indian Visitors: Rs. 50; Foreign Visitors: Rs. 200.

A Composite Entry Ticket: A package ticket to include visits to 8 different places that includes Jantar Mantar Observatory, Amber Fort, Nahargarh Fort, Sisodia Rani Garden, Albert Hall Museum, Hawa Mahal, Vidyadhar Gardens, Isarlat (Sargasuli). The tickets are available at the ticketing windows at Amber Fort, Albert Hall, Hawa Mahal, and Jantar Mantar (Observatory).
Indian Visitors: Rs. 300; Foreign Visitors: Rs. 1000
Indian Students: Rs. 40; Foreign Students: Rs.200;

Jantar Mantar Observatory in Jaipur will amaze you with the scientific, astronomical, and artistic expertise of the kings and scientists of the old times. To think of building a mammoth structure like this with such scientific precision, mathematical wizardry, without modern equipment is unimaginable. To see and experience this place is an experience of a lifetime.


See More: 

Jantar Mantar in Ujjain - One of the Oldest Observatories of the World

Jantar Mantar Observatory in Delhi