jantar mantar

JANTAR MANTARJANTAR MANTAR

Stone Astronomical ObservatoryStone Astronomical Observatory

Ancient India made some big Ancient India made some big advances in science because advances in science because it was in constant contact with it was in constant contact with other countries. After the other countries. After the conquest of the Indus basin by conquest of the Indus basin by Darius around 520 B.C. India Darius around 520 B.C. India was thrown wide open to was thrown wide open to Babylonian influences. Babylonian influences. Through the Persians, India Through the Persians, India also came into contact with also came into contact with Greece. All these contacts Greece. All these contacts greatly helped India in greatly helped India in enriching her sciences, enriching her sciences, particularly astronomy.particularly astronomy.

Darius

There is ample evidence to show that There is ample evidence to show that Aryabhata (499 A.D.) and Varahamihira (6th Aryabhata (499 A.D.) and Varahamihira (6th century A.D.) were well-acquainted with century A.D.) were well-acquainted with Greek astronomy. Greek astronomy.

The most celebrated astronomers after The most celebrated astronomers after Varahamihira were Brahmagupta (b.598 Varahamihira were Brahmagupta (b.598 A.D.), Lalla (8th cent.), Manjula or Munjala A.D.), Lalla (8th cent.), Manjula or Munjala (10th cent.), Shripati (c.1039 A.D.) and (10th cent.), Shripati (c.1039 A.D.) and Bhaskaracharya (b.1114 A.D.). Bhaskaracharya (b.1114 A.D.).

In the post-Bhaskara period not much In the post-Bhaskara period not much original work in astronomy and mathematics original work in astronomy and mathematics was done in India till modern times.was done in India till modern times.

AryabhataAryabhata

VarahamihiraVarahamihira

BhaskaracharyaBhaskaracharya

The Islamic world produced great The Islamic world produced great mathematician-astronomers:mathematician-astronomers:

Al-Khwarismi (780-850 A.D.)Al-Khwarismi (780-850 A.D.) Al-Battani (850-929 A.D.) Al-Battani (850-929 A.D.) Tabit ibn Qurra (836-901 A.D.) Tabit ibn Qurra (836-901 A.D.) Al-Sufi ( 10th cent.)Al-Sufi ( 10th cent.) Al-Biruni (973-1848 A.D.)Al-Biruni (973-1848 A.D.) Omar Khayyam (1048-1124 A.D.) Omar Khayyam (1048-1124 A.D.) Nasir al-din at-Tusi (1201-1274 A.D.). Nasir al-din at-Tusi (1201-1274 A.D.). The last one was in- charge of the The last one was in- charge of the

observatory at Maragha in Iran. observatory at Maragha in Iran.

In 1420 A.D., Ulugh Begh, grandson of In 1420 A.D., Ulugh Begh, grandson of Timur, built an observatory at Samarkand. Timur, built an observatory at Samarkand. Using very big but high-precision Using very big but high-precision instruments he prepared a Star catalogue instruments he prepared a Star catalogue which was much better than that of which was much better than that of Ptolemy.Ptolemy.

Samarkand

Maragha

After a long time Sawai Jai Singh II was After a long time Sawai Jai Singh II was the man from India who showed the the man from India who showed the greatest interest in Arabic/Persian greatest interest in Arabic/Persian astronomy. astronomy.

He was born in the ruling family of Amber He was born in the ruling family of Amber in Rajasthan in 1686 A.D., one year after in Rajasthan in 1686 A.D., one year after Newton published his book Principia. He Newton published his book Principia. He succeeded to the Amber throne at the age succeeded to the Amber throne at the age of thirteen.of thirteen.

Later on he was appointed by Mohammad Later on he was appointed by Mohammad Shah governor of the province of Agra and Shah governor of the province of Agra and then also of Malwa. From an early age Jai then also of Malwa. From an early age Jai Singh was very much interested in Singh was very much interested in astronomical observations and had astronomical observations and had acquired thorough knowledge of its acquired thorough knowledge of its principles and rules.principles and rules.

Jai Singh felt a great urge in reviving the Jai Singh felt a great urge in reviving the study of astronomy in India. With the aim of study of astronomy in India. With the aim of preparingpreparing new tables, Jai Singh at first new tables, Jai Singh at first started with the traditional brass started with the traditional brass instruments. Realising their inadequacy, he instruments. Realising their inadequacy, he discarded them in favour of stone and discarded them in favour of stone and masonry instruments of huge size. masonry instruments of huge size.

For observing the heavens Jai Singh built For observing the heavens Jai Singh built observatories at five places : observatories at five places : Delhi, Delhi, Jaipur, Mathura, Ujjain and Jaipur, Mathura, Ujjain and Varanasi.Varanasi. The first one was built in Delhi The first one was built in Delhi in year around 1724. These observatories, in year around 1724. These observatories, which in course of time came to be called which in course of time came to be called 'Jantar Mantar', housed a wide variety of 'Jantar Mantar', housed a wide variety of masonry and metal instruments. masonry and metal instruments.

Jai Singh, making use of the masonry and metal Jai Singh, making use of the masonry and metal instruments of his observatories, prepared the instruments of his observatories, prepared the astronomical treatise Zij-I -Muhammad Shah and astronomical treatise Zij-I -Muhammad Shah and dedicated it to the reigning monarch Muhammad Shah. dedicated it to the reigning monarch Muhammad Shah. The work was completed around 1727-28 A.D. The work was completed around 1727-28 A.D.

Jai Singh's court astronomer Pt.Jagannatha, who had Jai Singh's court astronomer Pt.Jagannatha, who had mastered in Arabic and Persian, translated from Arabic mastered in Arabic and Persian, translated from Arabic into Sanskrit works titled Rekhaganita and Siddhanta-into Sanskrit works titled Rekhaganita and Siddhanta-Samrata. The translation of the former was completed in Samrata. The translation of the former was completed in 1718 A.D. and of the latter in 1731 A.D.1718 A.D. and of the latter in 1731 A.D.

Jai Singh had established contacts with Jai Singh had established contacts with Jesuit missionaries in India and had also Jesuit missionaries in India and had also known the telescope. But he did not make known the telescope. But he did not make use of the Copernican revolution ushered use of the Copernican revolution ushered in Europe. He remained a firm follower of in Europe. He remained a firm follower of the geocentric system of Indian tradition the geocentric system of Indian tradition and of Ptolemy. It seems that Jai Singh and of Ptolemy. It seems that Jai Singh had no knowledge of the works of Kepler had no knowledge of the works of Kepler (1571-1630) or Newton (1642-1727).(1571-1630) or Newton (1642-1727).

Jai Singh want to determine new Jai Singh want to determine new planetary constants but his primary planetary constants but his primary interests in astronomy centered on the interests in astronomy centered on the moon. He was more interested in moon. He was more interested in observing and mathematically predicting observing and mathematically predicting the position of this heavenly body. He was the position of this heavenly body. He was also interested in the prediction of Solar also interested in the prediction of Solar eclipses and in calculation of the eclipses and in calculation of the occultation of stars and planets by the occultation of stars and planets by the moon.moon.

Jai Singh constructed 15 different types of instruments of masonry for his observatories. Out of these fifteen he himself invented seven instruments. According to the precession of the instruments it can be divide in following categories:

Low precision Masonary InstrumentsLow precision Masonary Instruments

Medium precision Masonary InstrumentsMedium precision Masonary Instruments

High precision Masonary InstrumentsHigh precision Masonary Instruments

Jai Singh Low precision Masonary InstrumentsJai Singh Low precision Masonary Instruments

InstrumentInstrument NumberNumber LocationLocation

DhruvadarsakaDhruvadarsaka 11 JaipurJaipur

NadivalayaNadivalaya 55 Jaipur,Varanasi,Ujjain,Mathura,Jaipur,Varanasi,Ujjain,Mathura,

UjjainUjjain

PalabhaPalabha 22 Jaipur UjjainJaipur Ujjain

AgraAgra 55 Jaipur,Varanasi,Ujjain,Mathura,UjjainJaipur,Varanasi,Ujjain,Mathura,Ujjain

SankuSanku 11 MathuraMathura

Unknown InstrumentUnknown Instrument 11 VaranasiVaranasi

Jai singh Medium precision Masonary InstrumentsJai singh Medium precision Masonary Instruments


JaiPrakasaJaiPrakasa 22 Delhi, JaipurDelhi, Jaipur

Rama YantraRama Yantra 22 Delhi, JaipurDelhi, Jaipur

Rasi ValayaRasi Valaya 1212 JaipurJaipur

Sara YantraSara Yantra 11 JaipurJaipur

DigamsaDigamsa 33 Varanasi,Ujjain,JaipurVaranasi,Ujjain,Jaipur

KapalaKapala 22 JaipurJaipur

Jai singh High precision Masonary InstrumentsJai singh High precision Masonary Instruments


SamratSamrat

66 Delhi,Jaipur(2),Ujjain,Varanasi(2)Delhi,Jaipur(2),Ujjain,Varanasi(2)

SasthamsaSasthamsa

55 Delhi, Jaipur(4)Delhi, Jaipur(4)

Daksinottara BhittiDaksinottara Bhitti

66 Jaipur,Varanasi(2),Ujjain,Mathura,Jaipur,Varanasi(2),Ujjain,Mathura,

DelhiDelhi

Instruments added after Jai SinghInstruments added after Jai Singh


Mishra YantraMishra Yantra 11 DelhiDelhi

Sanku YantraSanku Yantra 11 UjjainUjjain

Horizontal ScaleHorizontal Scale 11 JaipurJaipur

Measurements Related TermsMeasurements Related Terms

Azimuth: Azimuth: AzimuthAzimuth is is generally defined as a generally defined as a horizontal angle measured horizontal angle measured clockwise from any fixed clockwise from any fixed reference plane.In modern reference plane.In modern astronomy it is nearly astronomy it is nearly always measured clockwise always measured clockwise from the north base line or from the north base line or meridian. It measured in meridian. It measured in degree and tells about the degree and tells about the direction of a celestial body direction of a celestial body from the observer.from the observer.

Measurements Related TermsMeasurements Related Terms

Altitude: As a general Altitude: As a general definition, altitude is a definition, altitude is a distance measurement, distance measurement, usually in the vertical or usually in the vertical or "up" direction, between a "up" direction, between a reference line and a point reference line and a point or object. The reference or object. The reference line also often varies line also often varies according to the context. according to the context.

Measurements Related TermsMeasurements Related Terms MeridianMeridian : A : A meridianmeridian (or (or line of longitudeline of longitude) is an ) is an

imaginary arc on the Earth's surface from the North Pole to imaginary arc on the Earth's surface from the North Pole to the South Pole that connects all locations running along it the South Pole that connects all locations running along it with a given longitude. The position of a point on the with a given longitude. The position of a point on the meridian is given by the latitude .meridian is given by the latitude .

Zenith Distance:Zenith Distance: In general terms, the In general terms, the zenithzenith is the direction is the direction pointing directly "above" a particular location . The concept pointing directly "above" a particular location . The concept of "above" is more specifically defined in astronomy, of "above" is more specifically defined in astronomy, geophysics as the vertical direction opposite to the force of geophysics as the vertical direction opposite to the force of gravity at a given location. The opposite direction, i.e. the gravity at a given location. The opposite direction, i.e. the direction of the gravitational force is called the nadir. The direction of the gravitational force is called the nadir. The term zenith is also used to represent the highest point term zenith is also used to represent the highest point reached by a celestial body during its apparent orbit around reached by a celestial body during its apparent orbit around a given point of observation.a given point of observation.

Hour AngleHour Angle: In astronomy, the : In astronomy, the hour anglehour angle is one of the coordinates is one of the coordinates used in the equatorial coordinate system for describing the position of used in the equatorial coordinate system for describing the position of a point on the celestial sphere. The hour angle of a point is the angle a point on the celestial sphere. The hour angle of a point is the angle between the half plane determined by the Earth axis and the zenith between the half plane determined by the Earth axis and the zenith (half of the meridian plane) and the half plane determined by the (half of the meridian plane) and the half plane determined by the Earth axis and the given point. The angle is taken with minus sign if Earth axis and the given point. The angle is taken with minus sign if the point is eastward of the meridian plane and with the plus sign if the point is eastward of the meridian plane and with the plus sign if the point is westward of the meridian plane the point is westward of the meridian plane

LatitudeLatitude: : LatitudeLatitude, usually denoted by the Greek letter phi (, usually denoted by the Greek letter phi (φ) gives ) gives the location of a place on Earth (or other planetary body) north or the location of a place on Earth (or other planetary body) north or south of the equator. Technically, latitude is an angular measurement south of the equator. Technically, latitude is an angular measurement in degrees (marked with °) ranging from 0° at the equator (low in degrees (marked with °) ranging from 0° at the equator (low latitude) to 90° at the poles (90° N or +90° for the North Pole and 90° latitude) to 90° at the poles (90° N or +90° for the North Pole and 90° S or −90° for the South Pole). S or −90° for the South Pole).

EquinoxEquinox : An : An equinoxequinox occurs twice a year, when the tilt of the occurs twice a year, when the tilt of the Earth's axis is inclined neither away from nor towards the Sun, Earth's axis is inclined neither away from nor towards the Sun, the Sun being vertically above a point on the Equator. The term the Sun being vertically above a point on the Equator. The term equinoxequinox can also be used in a broader sense, meaning the date can also be used in a broader sense, meaning the date when such a passage happens. The name "equinox" is derived when such a passage happens. The name "equinox" is derived from the Latin from the Latin aequusaequus (equal) and (equal) and noxnox (night), because around (night), because around the equinox, the night and day are approximately equally long. the equinox, the night and day are approximately equally long.

Ecliptic Ecliptic The The eclipticecliptic is the apparent path that the Sun traces is the apparent path that the Sun traces out in the sky during the year. As it appears to move in the out in the sky during the year. As it appears to move in the sky in relation to the stars, the apparent path aligns with the sky in relation to the stars, the apparent path aligns with the planets throughout the course of the year. More accurately, it planets throughout the course of the year. More accurately, it is the intersection of a spherical surface, the celestial sphere, is the intersection of a spherical surface, the celestial sphere, with the with the ecliptic planeecliptic plane..

Equator :Equator : The The equatorequator (sometimes referred to colloquially as (sometimes referred to colloquially as "the Line""the Line") is the intersection of the Earth's surface with the ) is the intersection of the Earth's surface with the plane perpendicular to the Earth's axis of rotation and plane perpendicular to the Earth's axis of rotation and containing the Earth's center of mass. In simpler language, it containing the Earth's center of mass. In simpler language, it is an imaginary line on the Earth's surface approximately is an imaginary line on the Earth's surface approximately equidistant from the North Pole and South Pole that divides equidistant from the North Pole and South Pole that divides the Earth into a Northern Hemisphere and a Southern the Earth into a Northern Hemisphere and a Southern Hemisphere. Hemisphere.

Angle of Declination: Angle of Declination: Angle at a particular point on the Earth's Angle at a particular point on the Earth's surface between the direction of the true or geographic North surface between the direction of the true or geographic North Pole and the magnetic north pole. The angle of declination Pole and the magnetic north pole. The angle of declination has varied over time because of the slow drift in the position has varied over time because of the slow drift in the position of the magnetic north pole.of the magnetic north pole.

JANTAR MANTAR DELHI

Mishra YantraMishra Yantra

Samarat Gnomon

Quadrant

Second Quadrant

Samarat GnomonNiyata Cakra

Mishra YantraMishra Yantra

Mishra Yantra consists of several instruments within the single Mishra Yantra consists of several instruments within the single structure. The instruments included in the structure are as structure. The instruments included in the structure are as followsfollows::

1.Daksinottra Bhitti1.Daksinottra Bhitti : for measuring the zenith distance or : for measuring the zenith distance or altitude of sun and other planets.altitude of sun and other planets.

2.Karkarasi Valaya::2.Karkarasi Valaya:: Instrument is now in ruins. Application is Instrument is now in ruins. Application is not known and according to the theory it was used to measure not known and according to the theory it was used to measure directly the longitude of celestial body.directly the longitude of celestial body.

3.Samarat Yantra3.Samarat Yantra : for measuring the local time. : for measuring the local time.

4. Niyata Cakras:4. Niyata Cakras: for measuring the declination of an object at for measuring the declination of an object at interval of a few hours as the object travels from east to west in interval of a few hours as the object travels from east to west in the sky.the sky.

5. Quadrant arc5. Quadrant arc of unknown function of unknown function

Samarat YantraSamarat Yantra

Samarat YantraSamarat Yantra The primary object of Samarat is to indicate the solar The primary object of Samarat is to indicate the solar

time or local time of a place.time or local time of a place.

By knowing the time of the meridian transit of By knowing the time of the meridian transit of prominent star and observing the hour angle of the prominent star and observing the hour angle of the star or its angular distance from meridian time at star or its angular distance from meridian time at night may also calculated from this instrument.night may also calculated from this instrument.

In addition to marking local time the Samarat Yantra In addition to marking local time the Samarat Yantra was used to determine the sun declination and the was used to determine the sun declination and the right ascension of any celestial object.right ascension of any celestial object.

Jai Prakesh YantraJai Prakesh Yantra

Jai Prakash YantraJai Prakash Yantra Twin hemispherical bowls of Jai Prakas yantra are each a Twin hemispherical bowls of Jai Prakas yantra are each a

reflection of the sky above. The bowls are marked in sectors reflection of the sky above. The bowls are marked in sectors and gaps. Observers move inside the gap regions and make and gaps. Observers move inside the gap regions and make observations using the markings on the sectors. The observations using the markings on the sectors. The instruments are complimentary, in the sense that where there is instruments are complimentary, in the sense that where there is a gap in one of the bowl, is a sector placed in the other bowl a gap in one of the bowl, is a sector placed in the other bowl and vice versa. Spliced together, they make a whole bowl that and vice versa. Spliced together, they make a whole bowl that is a complete reflection of the sky above. is a complete reflection of the sky above.

Cross wires are stretched in the North-South and East-West Cross wires are stretched in the North-South and East-West direction on the surface of the instrument bowls. Shadow of the direction on the surface of the instrument bowls. Shadow of the centre of this cross wire, on the surface of the bowl, shows the centre of this cross wire, on the surface of the bowl, shows the position of the Sun in the sky. position of the Sun in the sky.

The instrument can measure the local co-ordinates of a The instrument can measure the local co-ordinates of a celestial object - the Altitude and Azimuth. celestial object - the Altitude and Azimuth.

Rama YantraRama Yantra

Jantar MantarJantar Mantar

JaipurJaipur

Jaipur, Jantar Mantar was the second and more sophisticated Jaipur, Jantar Mantar was the second and more sophisticated observatory Jai singh built.The instruments were so big and observatory Jai singh built.The instruments were so big and accurate ,as they were built of stone,masonry and marble. accurate ,as they were built of stone,masonry and marble. There are 18 instruments in the Jaipur observatory. He There are 18 instruments in the Jaipur observatory. He procured latest astronomical books and instruments from procured latest astronomical books and instruments from Europe.Some he had translated in Sanskrit.Some of these Europe.Some he had translated in Sanskrit.Some of these translated texts are on display in the City Palace Museum. translated texts are on display in the City Palace Museum.

Samrat YantraSamrat Yantra

By far the biggest yantra in Jantar Mantar. it is a huge Sun By far the biggest yantra in Jantar Mantar. it is a huge Sun Dial. It is 89 feet high and 148 feet wide. It can measure Dial. It is 89 feet high and 148 feet wide. It can measure local time correctly up to 2 seconds..local time correctly up to 2 seconds..

Chakra YantraChakra Yantra

The Jaipur observatory has two unit of Cakra Yantra. The Jaipur observatory has two unit of Cakra Yantra. Instrument is made of heavy molded brass and pivoted to Instrument is made of heavy molded brass and pivoted to rotate freely about a diameter parallel to the earth axis. rotate freely about a diameter parallel to the earth axis. Objective of the instrument is to measure the declination Objective of the instrument is to measure the declination and hour angle of celestial body.and hour angle of celestial body.

For measuring the declination and hour angle of an object, For measuring the declination and hour angle of an object, a sighting tube is mounted at the centre of the instrument. a sighting tube is mounted at the centre of the instrument. The tube with a pointer attached to it, rotates about a The tube with a pointer attached to it, rotates about a perpendicular axis passing through the centre of cakra perpendicular axis passing through the centre of cakra ring. The observer rotating the cakra about its polar axis ring. The observer rotating the cakra about its polar axis and the tube about the centre obtains the object in sight and the tube about the centre obtains the object in sight and the hour angle off the plate at the post. and the hour angle off the plate at the post.

Rashivalaya YantraRashivalaya Yantra

The Rasivalaya are a set of 12 instruments based on the The Rasivalaya are a set of 12 instruments based on the principle of samarat yantra are designed for directly principle of samarat yantra are designed for directly measuring the latitude and longitude of a celestial object.measuring the latitude and longitude of a celestial object.

Rasivalaya were also invented by Jai Singh. A particular Rasivalaya were also invented by Jai Singh. A particular Rasivalaya instrument become operative when first point Rasivalaya instrument become operative when first point of sign of the zodiac it represents approaches the of sign of the zodiac it represents approaches the meridian.meridian.

At that moment its gnomon point towards the pole of At that moment its gnomon point towards the pole of ecliptic and its guardant become parallel to the ecliptic. ecliptic and its guardant become parallel to the ecliptic.

There are 12 signs of the zodiac, so there are 12 There are 12 signs of the zodiac, so there are 12 Rasivalayas representing each sign.Rasivalayas representing each sign.

Narivalaya YantraNarivalaya Yantra

This is an effective tool for demonstrating the This is an effective tool for demonstrating the passage of sun across the celestial equator.passage of sun across the celestial equator.

On the vernal equinox and the autumnal equinox On the vernal equinox and the autumnal equinox the rays of the sun fall parallel to two opposing the rays of the sun fall parallel to two opposing faces of plates and illuminate them both. Other faces of plates and illuminate them both. Other time only one or other face remains in the sun.time only one or other face remains in the sun.

After the sun has crossed the equator around 21 After the sun has crossed the equator around 21 March its illuminate the northern face for sixth March its illuminate the northern face for sixth months. After 21 September it is the southern months. After 21 September it is the southern face that receives the rays of the sun for the face that receives the rays of the sun for the next six months.next six months.

Jai Singh built Nadivalays at each his Jai Singh built Nadivalays at each his observatory site except Delhi.observatory site except Delhi.

Yantra RajYantra Raj Great astrolabe is suspended Great astrolabe is suspended

from massive wooden beam from massive wooden beam supported by tall pillars.supported by tall pillars.

Orientation of the pillars is Orientation of the pillars is such that the line joining them such that the line joining them makes an angle of about 23 makes an angle of about 23 degree with the plane of degree with the plane of meridian.meridian.

This is the largest instrument This is the largest instrument in the world for its kind. in the world for its kind. Instrument is built for the Instrument is built for the latitude of Jaipur as there are latitude of Jaipur as there are 27 degree making between the 27 degree making between the zenith and the pole.zenith and the pole.

The main function of the The main function of the instrument is to measure time.instrument is to measure time.

Krantiwrita YantraKrantiwrita Yantra

This is the unfinished structure and has two This is the unfinished structure and has two circular plates. Both the plates have a scale circular plates. Both the plates have a scale which is divide in degrees.which is divide in degrees.

Unnatasha YantraUnnatasha Yantra

Unnatamsa can measure the Altitude of a celestial object.

The large graduated brass circle hung from the supporting beam, is the measuring instrument of the Unnatamsa. The brass circle is pivoted to rotate freely around a vertical axis. The ring has two cross beams in the vertical and horizontal directions. A sighting tube is pivoted at the centre of the circle, which can be moved in the vertical direction, to align towards any celestial object.

The rim of the brass circle has graduations marked in such a way that smallest division is a tenth of a degree. The larger divisions of 1 degree and of 6 degrees are also marked on the circle. After sighting the celestial object, its Altitude can be read from the position of the pointer.

Dakshinodak Bhitti YantraDakshinodak Bhitti Yantra

Daksinottara BittiDaksinottara Bitti

Daksinottara Bitti yantra consists of a Daksinottara Bitti yantra consists of a graduated quadrant or a semicircle inscribed graduated quadrant or a semicircle inscribed on a north-south wall. At the centre of the are on a north-south wall. At the centre of the are is a horizontal rod. The instrument is used for is a horizontal rod. The instrument is used for measuring the meridian attitude or the zenith measuring the meridian attitude or the zenith distance of an object such as the sun, the moon distance of an object such as the sun, the moon or a planet.or a planet.

Jai Prakash YantraJai Prakash Yantra

Kapala YantraKapala Yantra

The Kapala are built as two hemispherical units, each The Kapala are built as two hemispherical units, each hemisphere being a complete reflection of the sky hemisphere being a complete reflection of the sky overhead. overhead.

The western Kapala unit is built for observations while The western Kapala unit is built for observations while the eastern segment is meant for theoretical the eastern segment is meant for theoretical conversions of co-ordinates from one system to conversions of co-ordinates from one system to another. The western Kapala unit is analogous to the another. The western Kapala unit is analogous to the Jaiprakas – a hemispherical bowl on which every Jaiprakas – a hemispherical bowl on which every point is a reflection of a point in the sky. point is a reflection of a point in the sky.

By looking at the shadow of a cross wire stretched By looking at the shadow of a cross wire stretched over its surface, the co-ordinates of the Sun in the over its surface, the co-ordinates of the Sun in the sky, can be determined with the western Kapalasky, can be determined with the western Kapala. .

The yantra hare a diameter of 3.46 m each and are so named because by there resemblance to the brain cover of human skill.

Jai Praksa and the Kapala are both multipurpose instruments consisting of hemispherical surface of concave shape and inscribed width of number of arcs.

These arcs indicate the local time and they measure astronomical parameter,such as co-ordinates of celestial body.

One difference between the two instruments is that Kapala indicates the a ppp while Jay Praksa observe the sign of meridian. Another is that Jay Praksa built in two complementary halves,

Ram YantraRam Yantra

The Rama yantra, probably named after Rama Singh The The Rama yantra, probably named after Rama Singh The grandfather of Jai Singh.grandfather of Jai Singh.

This yantra is used to measure the azimuth and altitude of This yantra is used to measure the azimuth and altitude of a celestial object, for example sun.a celestial object, for example sun.

Cylindrical structure of Rama Yantra is open at the top and Cylindrical structure of Rama Yantra is open at the top and its height equals its radius. its height equals its radius.

For measuring the azimuth, circular scales with their For measuring the azimuth, circular scales with their centre at the axis of cylindrical walls. The scales are centre at the axis of cylindrical walls. The scales are divided into degree and minutes.divided into degree and minutes.

In day time the coordinates of a sun are determined by In day time the coordinates of a sun are determined by observing the shadow of the pillar top end on the scales.observing the shadow of the pillar top end on the scales.

The coordinates of the moon when it is bright enough to The coordinates of the moon when it is bright enough to cast a shadow, may also be read in a similar manner.cast a shadow, may also be read in a similar manner.

JANTAR MANTAR UJJAINJANTAR MANTAR UJJAIN


Daksinottara Bitti yantra consists of a Daksinottara Bitti yantra consists of a graduated quadrant or a semicircle inscribed graduated quadrant or a semicircle inscribed on a north-south wall. At the centre of the are on a north-south wall. At the centre of the are is a horizontal rod. The instrument is used for is a horizontal rod. The instrument is used for measuring the meridian attitude or the zenith measuring the meridian attitude or the zenith distance of an object such as the sun, the moon distance of an object such as the sun, the moon or a planet. or a planet.

Samarat YantraSamarat Yantra

SANKU

DIGAMASA

Digmasa YantraDigmasa Yantra This consists of two cylindrical wall surrounding a centre This consists of two cylindrical wall surrounding a centre

pillar measure the angle of azimuth of a celestial body. pillar measure the angle of azimuth of a celestial body.

Its centre pillar as well as its wall are engraved in degrees and Its centre pillar as well as its wall are engraved in degrees and numbers at their top level. numbers at their top level.

Cross wires are stretched between the coordinal points marked Cross wires are stretched between the coordinal points marked over the outer wall. The observer uses one or more strings over the outer wall. The observer uses one or more strings with one end tied to a knob on the pillar and other end to stone with one end tied to a knob on the pillar and other end to stone pebbles suspended over the walls, with these strings the pebbles suspended over the walls, with these strings the observer defines a vertical plane contain the cross wire and the observer defines a vertical plane contain the cross wire and the object in the sky. The angular distance of the vertical plane object in the sky. The angular distance of the vertical plane from the north point, read on the scales indicate the azimuth of from the north point, read on the scales indicate the azimuth of body.body.

Jantar Mantar at VaranasiJantar Mantar at Varanasi

Some Glimpses of Jantar Mantar Varanasi

Jantar Mantar at VaranasiJantar Mantar at Varanasi

Observatory at Vanarasi has following Instruments:Observatory at Vanarasi has following Instruments: Samarat YantraSamarat Yantra DigamsaDigamsa NadivalayaNadivalaya Cakra YantraCakra Yantra Daksinottara BhittiDaksinottara Bhitti Unidentified structureUnidentified structure

SMRAT YANTRA -------->

<------ DIGAMSA YANTRA

<----- Nadivalaya Yantra

Samarat Yantra ---------->

Jantar Mantar MathuraJantar Mantar Mathura

The Observatory was built within the local fort on the banks of the river Yamuna

It is believed that the observatory at Mathura It is believed that the observatory at Mathura disappeared about 1850 a few years before the disappeared about 1850 a few years before the unsuccessful uprising of 1857 against the unsuccessful uprising of 1857 against the British. British.

At Mathura there were following instruments:At Mathura there were following instruments:• NadivalayaNadivalaya• Agra YantraAgra Yantra• SankuSanku• Daksinottara BittiDaksinottara Bitti

In spite of his best efforts for the revival of In spite of his best efforts for the revival of astronomical studies in India, Jaya Singh astronomical studies in India, Jaya Singh remained firmly attached to the medieval remained firmly attached to the medieval tradition. He died in 1743 A.D., exactly tradition. He died in 1743 A.D., exactly two hundred years after Copernicus two hundred years after Copernicus (1473-1543). Today Jaya Singh's work is (1473-1543). Today Jaya Singh's work is only a tradition and his observatories are only a tradition and his observatories are nothing but archaeological remains.nothing but archaeological remains.

THANKSTHANKS

Prepared By:Prepared By:

Sandipan DharSandipan Dhar

jantar mantar

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