Jantar Mantar | A must visiting place in Jaipur | Astronomical Significance| যন্তর মন্তর| জয়পুর скачать в хорошем качестве

Jantar Mantar | A must visiting place in Jaipur | Astronomical Significance| যন্তর মন্তর| জয়পুর

During the early 18th century scientific consciousness grown in the mind of the then king of Jaipur, Sawai Jai singh II. He wanted to be observer of stars and planets. Hence betweens 1728-1734 AD he commissioned the construction of Jantar Mantar which constitutes 19 astronomic instruments including a large sundial.He made 5 jantar mantar in India. Jantar Mantar in Jaipur and Delhi are still functional while in a dilapidated condition in Mathura and Ujjain.A Jantar Mantar in Varanasi is also on the verge of ruination. observatory consists of nineteen instruments for measuring time, predicting eclipses, tracking location of major stars as the Earth orbits around the Sun, ascertaining the declinations of planets, and determining the celestial altitudes and related ephemerides. The instruments are (alphabetical): .Chakra Yantra (four semicircular arcs on which a gnomon casts a shadow, thereby giving the declination of the Sun at four specified times of the day. This data corresponds to noon at four observatories around the world (Greenwich in UK, Zurich in Switzerland, Notke in Japan and Saitchen in the Pacific); this is equivalent of a wall of clocks registering local times in different parts of the world.) Dakshin Bhitti Yantra (measures meridian, altitude and zenith distances of celestial bodies) Digamsha Yantra (a pillar in the middle of two concentric outer circles, used to measure azimuth of the sun and to calculate the time of sunrise and sunset forecasts) Disha Yantra (used to detect the direction) Dhruva Darshak Pattika (observe and find the location of pole star with respect to other celestial bodies) Jai Prakash Yantra (two hemispherical bowl-based sundials with marked marble slabs that map inverted images of sky and allow the observer to move inside the instrument; measures altitudes, azimuths, hour angles, and declinations) Kapali Yantra (measures coordinates of celestial bodies in azimuth and equatorial systems; any point in sky can be visually transformed from one coordinate system to another) Kanali Yantra Kranti Vritta Yantra (measures longitude and latitude of celestial bodies) Laghu Samrat Yantra (the smaller sundial at the monument, inclined at 27 degrees, to measure time, albeit less accurately than Vrihat Samrat Yantra) Misra Yantra (meaning mixed instrument, it is a compilation of five different instruments) Nadi Valaya Yantra (two sundials on different faces of the instrument, the two faces representing north and south hemispheres; measuring the time to an accuracy of less than a minute) Palbha Yantra Rama Yantra (an upright building used to find the altitude and the azimuth of the Sun) Rashi Valaya Yantra (12 gnomon dials that measure ecliptic coordinates of stars, planets and all 12 constellation systems) Shastansh Yantra (next to Vrihat Samrat Yantra) This instrument has a 60-degree arc built in the meridian plane within a dark chamber. At noon, the Sun's pinhole image falls on a scale below enabling the observer to measure the zenith distance, declination, and the diameter of the Sun.) Unnatamsa Yantra (a metal ring divided into four segments by horizontal and vertical lines, with a hole in the middle; the position and orientation of the instrument allows measurement of the altitude of celestial bodies) Vrihat Samrat Yantra (world's largest gnomon sundial, measures time in intervals of 2 seconds using shadow cast from the sunlight) Yantra Raj Yantra (a 2.43-metre bronze astrolabe, one of the largest in the world, used only once a year, calculates the Hindu calendar) The Vrihat Samrat Yantra, which means the "great king of instruments", is 88 feet (27 m) high, making it one of the world's largest sundials. Its face is angled at 27 degrees, the latitude of Jaipur. It is purported to tell the time to an accuracy of about two seconds in Jaipur local time. Its shadow moves visibly at 1 mm per second, or roughly a hand's breadth (6 cm) every minute, The Hindu chhatri (small cupola) on top is used as a platform for announcing eclipses and the arrival of monsoons. The instruments are in most cases huge structures. The scale to which they have been built has been alleged to increase their accuracy. However, the penumbra of the sun can be as wide as 30 mm, making the 1mm increments of the Samrat Yantra sundial devoid of any practical significance. Additionally, the masons constructing the instruments had insufficient experience with construction of this scale, and subsidence of the foundations has subsequently misaligned them.