A Jantar Mantar (

Hindustani Hindustani may refer to: * something of, from, or related to Hindustan (another name of India) * Hindustani language, an Indo-Aryan language, whose two official norms are Hindi and Urdu * Fiji Hindi, a variety of Eastern Hindi spoken in Fiji, and ...

pronunciation: ͡ʒən̪t̪ər mən̪t̪ər is an assembly of stone-built astronomical instruments, designed to be used with the naked eye. There were five Jantar Mantars in India, all of them built at the command of the Rajah Jai Singh II, who had a keen interest in mathematics, architecture and astronomy; The largest example is the equinoctial

sundial A sundial is a horological device that tells the time of day (referred to as civil time in modern usage) when direct sunlight shines by the apparent position of the Sun in the sky. In the narrowest sense of the word, it consists of a flat ...

belonging to Jaipur's assembly of instruments, consisting of a gigantic triangular

gnomon A gnomon (; ) is the part of a sundial that casts a shadow. The term is used for a variety of purposes in mathematics and other fields. History A painted stick dating from 2300 BC that was excavated at the astronomical site of Taosi is the ol ...

with the hypotenuse parallel to the Earth's axis. On either side of the gnomon is a quadrant of a circle, parallel to the plane of the

equator The equator is a circle of latitude, about in circumference, that divides Earth into the Northern and Southern hemispheres. It is an imaginary line located at 0 degrees latitude, halfway between the North and South poles. The term can als ...

. The instrument can be used with an accuracy of about 2 seconds by a "skilled observer" to measure the time of day, and the

declination In astronomy, declination (abbreviated dec; symbol ''δ'') is one of the two angles that locate a point on the celestial sphere in the equatorial coordinate system, the other being hour angle. Declination's angle is measured north or south of the ...

of the Sun and the other

heavenly bodies "Heavenly Bodies" is a song written by Elaine Lifton, Gloria Nissenson and Lee Ritenour, and recorded by American country music artist Earl Thomas Conley. It was released in May 1982 as the first single from the album '' Somewhere Between Right ...

. It is the world's largest stone sundial, known as the Vrihat Samrat Yantra. The Jaipur Jantar Mantar is a UNESCO World Heritage Site.Unesco listing for Jantar Mantar
accessed July 30 2021

History

In the early 18th century, Maharaja Jai Singh II of Jaipur constructed five Jantar Mantar in total, in New Delhi, Jaipur,

Ujjain Ujjain (, Hindustani language, Hindustani pronunciation: Help:IPA/Hindi and Urdu, �d͡ːʒɛːn is a city in Ujjain district of the States and territories of India, Indian state of Madhya Pradesh. It is the fifth-largest city in Madhya Prad ...

, Mathura and Varanasi; they were completed between 1724 and 1735. The Jantar have like Samrat Yantra, Jai Prakash, Ram Yantra and Niyati Chakra; each of which are used to for various astronomical calculations. The primary purpose of the observatory was to compile astronomical tables and to predict the times and movements of the sun, moon and

planets A planet is a large, rounded astronomical body that is neither a star nor its remnant. The best available theory of planet formation is the nebular hypothesis, which posits that an interstellar cloud collapses out of a nebula to create a young ...

. List of instruments: ● Samrat Yantra ● Jai Prakash Yantra ● Disha Yantra ● Rama Yantra ● Chakra Yantra ● Rashiwalya Yantra ● Dingash Yantra ● Utaansh Yantra

Name

The name "Jantar Mantar" is at least 200 years old, finding a mention in an account from 1803. However, the archives of Jaipur State, such as accounts from 1735 and 1737–1738, do not use this as ''Jantra'', which in the spoken language is corrupted to ''Jantar''. The word ''Jantra'' is derived from '' yantra'', instrument, while the suffix ''Mantar'' is derived from mantrana meaning consult or calculate. The words ''jantar'' and ''mantar'' (or ''yantra'' and ''mantra'') mean calculation instrument.

References

External links

Jantar Mantar - The Astronomical Observatories of Jai Singh II
"a project initiated by Cornell University Professor of Art, Barry Perlus"

Jantar Mantar Jaipur Timings, Entry Fee

India's mysterious gateway to the stars
BBC Travel (2022-05-31) {{Coord, 26, 55, 28, N, 75, 49, 29.5, E, source:dewiki_region:IN, display=title Ancient astronomical observatories Archaeoastronomy Astronomical observatories in India Buildings and structures in Delhi History of science and technology in India Rajput architecture

History

Name

See also

References

External links