π¬ Science in India
5,000 years of science in India
From Harappan bronze and planned drains to zero, the Kerala School, the Raman effect and missions to the Moon β one timeline of what was discovered, invented and built in India. Every milestone links to the source it comes from.
Fields of knowledge
The timeline
Harappan and early India
π Explore by field β-
c. 1.5 million years agoβ Metals and materials
Stone hand-axes at Attirampakkam
π Tamil NaduAcheulian hand-axes and cleavers β some of the oldest tools made by early humans in South Asia.
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c. 385,000β172,000 years agoβ Metals and materials
Smaller, finer stone tools
π Attirampakkam, Tamil NaduA Middle Palaeolithic culture of prepared-core tools, far earlier than once thought.
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from c. 7000 BCEπΎ Farming and plants
Farming begins at Mehrgarh
π Mehrgarh, BalochistanOne of the earliest farming villages of the subcontinent, excavated and dated by French archaeologists.
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7,500β9,000 years agoπ©Ί Medicine and life sciences
The earliest dentistry
π Mehrgarh, BalochistanEleven molar teeth from nine adults were drilled β with flint tips β while the people were alive.
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Neolithic periodβ Metals and materials
Early cotton
π Mehrgarh, BalochistanCotton fibres preserved inside a copper bead β the first evidence of cotton at Neolithic Mehrgarh.
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Early HarappanπΎ Farming and plants
A ploughed field and terracotta ploughs
π Kalibangan, RajasthanA field with two sets of furrows at right angles β two crops grown together; terracotta plough models were found in Cholistan and at Banawali.
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Harappan periodβ Metals and materials
Copper and bronze metallurgy
π Harappan citiesThe Harappan civilisation mastered copper and bronze metallurgy β a technology that made its cities possible.
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Harappan civilizationπ Language, writing and learning
The Harappan script
π Harappan citiesShort inscriptions on seals β some 375 to 400 signs, the longest about 26 signs long. It is still undeciphered.
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Harappan civilizationπ Engineering, water and towns
Planned drainage
π Mohenjo-daro, Harappa and other citiesA planned drainage system in Harappan cities β evidence of town planning.
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Harappan periodπ Engineering, water and towns
Bricks of a standard ratio
π Harappan settlementsSun-dried or baked, Harappan bricks kept one ratio β length four times and breadth twice the height β and were used at all Harappan settlements, a sign the towns were planned first and then built.
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c. 2500 BCEβ Metals and materials
Lost-wax bronze casting
π Mohenjo-daroThe βlost-waxβ (cire-perdu) casting process was learnt as long ago as the Indus Valley Culture; the βDancing Girlβ from Mohenjodaro is perhaps the earliest bronze sculpture, datable to 2500 BCE. Tribal craftspeople still use the process today.
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Harappan civilizationβ Mathematics
Standard weights
π Harappan citiesA precise system of weights, usually cubes of a stone called chert, regulated trade.
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Harappan periodβ Metals and materials
Drilling hard stone beads
π Chanhudaro, Lothal, DholaviraBeads of carnelian and other stones were shaped, ground, polished and drilled; specialised drills have been found at Chanhudaro, Lothal and Dholavira.
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Harappan periodβ Mathematics
Scales and units of length
π Harappan sitesObjects with ruled markings that could be scales have been found at Harappan sites. Later Indian literature names units such as the angula (finger width), dhanusa and yojana, used for artefacts, architecture and town planning β and carpenters and tailors still use the angula.
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Harappan civilizationπ Engineering, water and towns
The wheel: terracotta carts
π Harappan sitesTerracotta models of wheeled carts show wheeled transport in Harappan times.
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Harappan periodπ Engineering, water and towns
The dockyard at Lothal
π Lothal, GujaratA huge brick basin at the Harappan settlement of Lothal, which NCERT presents as a dockyard linked to trade.
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c. 3000β1500 BCEπ Engineering, water and towns
Water management at Dholavira
π Dholavira, GujaratA sophisticated water-management system let a walled city thrive on an arid island.
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1800β1000 BCEβ Metals and materials
Iron working in the Ganga plain
π Uttar PradeshIron artefacts, furnaces, tuyeres and slag in layers radiocarbon-dated between 1800 and 1000 BCE.
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Vedic periodβ Mathematics
Number names and fractions in the Vedas
The Yajurveda Samhita lists names for powers of ten β eka, dasha, shata, sahasra, ayuta and on up to 10ΒΉΒ² and beyond; the Rig Veda calls the fraction three-quarters tri-pada.
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c. 800 BCE (Baudhayana)β Mathematics
The Sulba-sutras: geometry with a rope
Geometric texts of the Vedic period on building fire altars β the earliest known Indian texts with methods to construct perpendiculars and perpendicular bisectors, using a rope as the compass. Baudhayanaβs Sulbasutra (c. 800 BCE) already works with non-unit fractions.
Ancient and classical
π Explore by field β-
c. 600β500 BCEπΎ Farming and plants
Paddy transplantation
π Ganga valleyTransplanting rice seedlings spread in the Ganga valley, alongside the growth of towns.
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c. 500 BCEπ Language, writing and learning
Paniniβs Ashtadhyayi
The Ashtadhyayi of Panini, a work on Sanskrit grammar.
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Mauryan timesπ Language, writing and learning
Takshashila, a centre of learning
π Takshashila (Taxila)According to Buddhist texts, Kautilya β author of the Arthashastra, βthe science of governance and economicsβ β was a teacher at the world-renowned Takshashila university.
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3rd century BCEπ Language, writing and learning
Brahmi: Ashoka's inscriptions
π Across the Mauryan EmpireEdicts carved in the Brahmi script β deciphered by James Prinsep only in 1838.
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Ancient and medieval periodsβ Metals and materials
Wootz steel
π South IndiaThe famed 'wootz': high-carbon steel made in crucibles in South India.
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2nd century BCE β 3rd century CEπ Astronomy
Shadow clocks and water clocks
The earliest reference to measuring time by shadows is in Kautilyaβs Arthasastra, which also describes a water clock with water flowing out.
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c. 100 CE; final shape in the Gupta periodπ©Ί Medicine and life sciences
Charaka and Sushruta Samhitas
Works on medicine in Sanskrit. Ayurveda has much older roots, but these texts β which deal with cataloguing and diagnosing diseases, among other topics β were compiled and given their final shape during the Gupta period.
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Karikalaβs reignπ Engineering, water and towns
The Kallanai (Grand Anicut)
π Kaveri, below SrirangamA complex water-diversion system built by the Chola king Karikala just downstream of Srirangam island, sending Kaveri waters to the central and southern delta so that more land could be irrigated.
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c. second century CEπ Engineering, water and towns
Sudarshana lake, a reservoir
π Girnar, GujaratAn artificial reservoir known from a Sanskrit rock inscription recording the achievements of the Shaka ruler Rudradaman, who rebuilt it.
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as early as the 3rd or 4th century CEβ Mathematics
Zero: the Bakhshali manuscript
π Bakhshali (now in Pakistan)A mathematical text with hundreds of zeros written as dots β the oldest recorded origin of the zero symbol we use today.
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3rd century BCE β 13th century CEπ Language, writing and learning
Nalanda Mahavihara
π Nalanda, BiharThe most ancient university of the Indian subcontinent, teaching without a break for some 800 years.
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Ancient periodβ Metals and materials
The rust-resistant iron pillar
π DelhiAn ancient iron pillar that has resisted corrosion for centuries β a puzzle explained by metallurgists.
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around 500 CEπ Astronomy
Aryabhata and the Aryabhatiya
π Kusumapura (near Patna)A short treatise of mathematics and astronomy. Aryabhata proposed that the Earth spins on its axis, gave the length of the year within minutes of the modern value, estimated the size of the Earth and correctly explained solar and lunar eclipses. His value for one rotation of the Earth is about 23 hours 56 minutes 4.1 seconds.
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499 CEβ Mathematics
Aryabhata computes with ten digits
Aryabhata was the first mathematician to fully explain, and do elaborate scientific computations with, the Indian system of ten symbols; he also first proposed a systematic way to solve problems with a single unknown.
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Aryabhataβs timeπ Astronomy
The Ghatika-yantra (sinking-bowl water clock)
Because outflow clocks slowed as the water dropped, a sinking-bowl water clock was developed β first mentioned by Aryabhata. It kept time at monasteries, palaces and town squares, where each sinking of the bowl was announced; the day was divided into 60 ghatis.
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Gupta periodπ Astronomy
Varahamihiraβs Brihat Samhita
π Ujjayini (Ujjain)An encyclopedic work covering astronomy and astrology, weather forecasting, architecture, town planning and even farming.
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around 530 CEπ Astronomy
Time from a stickβs shadow
Varahamihira gave an accurate expression for time in terms of the shadow of a vertical stick.
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born 598 CEβ Mathematics
Brahmagupta: rules for zero
π BhillamalaIn the Brahmasphutasiddhanta he gave the rules of arithmetic with zero, negative numbers and fractions. His works were later translated into Persian and Latin.
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6thβ10th centuriesβ Mathematics
Bhaskara I and trigonometry
Bhaskara I did pioneering work in trigonometry and wrote a lengthy commentary on the Aryabhatiya.
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628 CEβ Mathematics
Brahmaguptaβs rules for fractions
The Brahmasphutasiddhanta first stated in general form how to add, subtract, multiply and divide fractions β the methods still taught today. These ideas reached Europe through the Arabs.
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c. 700 CEβ Mathematics
Virahankaβs numbers
Counting the rhythms of short and long syllables in poetry, the Prakrit scholar Virahanka gave the rule for the sequence 1, 2, 3, 5, 8, 13, 21β¦ β the first known person to write it down. It is now called the VirahankaβFibonacci sequence.
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late 8th centuryπ Language, writing and learning
Vikramashila university
π Banks of the Ganga, BiharFounded by the Pala king Dharmapala, it remained a great centre of learning for more than four centuries, with six colleges, a vast library and nearly 3,000 scholars. Each college had a βscholar gatekeeperβ who set the admission test.
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9th centuryβ Mathematics
Indian numerals reach the Arab world
π BaghdadSanskrit texts of mathematics, astronomy and medicine were translated into Arabic. The Arabs adopted Indiaβs decimal numeral system with the zero; in Europe these became known as βArabic numeralsβ.
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c. 825 CEβ Mathematics
Al-Khwarizmiβs βHindu numeralsβ
π BaghdadThe Indian number system reached the Arab world by around 800 CE and was popularised there by Al-Khwarizmiβs book On the Calculation with Hindu Numerals (c. 825) and Al-Kindiβs On the Use of the Hindu Numerals (c. 830).
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c. 850 CEβ Mathematics
Mahaviracharyaβs Ganita-sara-sangraha
Mahaviracharya developed the arithmetic of fractions further and, in the Ganita-sara-sangraha, named the powers of ten up to 10Β²Β³.
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10th centuryβ Mathematics
The Chautisa Yantra magic square
π KhajurahoThe first recorded 4 Γ 4 magic square, in an inscription at the Parshvanath Jain temple: every row, column and diagonal adds up to 34.
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around the 10th century CEπΎ Farming and plants
Surapalaβs Vrikshayurveda
A text of plant science: which plants suit which soils, seed collection and treatment, irrigation by species and season, and natural pest control.
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11th centuryπ Astronomy
Al-Biruni studies Indian science
π GhazniAl-Biruni learnt Sanskrit and wrote an encyclopaedic survey of India, compiling in mathematics and astronomy what he could gather from the works of Aryabhata, Varahamihira and Brahmagupta.
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11th centuryπ Engineering, water and towns
Stepwells: Rani-ki-Vav
π Patan, GujaratStepwells stored underground water in India since the 3rd millennium BCE; this one is a masterpiece of the craft.
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born 1114β Mathematics
Bhaskaracharyaβs Lilavati
π probably present-day MaharashtraOne of Indiaβs greatest mathematicians and astronomers: Lilavati (1150 CE) teaches mathematics through riddles, Bijaganita covers advanced algebra and Siddhantashiromani astronomical calculation. Several of his works were translated into Persian in the Mughal period.
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Bhaskara IIβs timeπ Astronomy
Watching the sky in bowls of water
More than 800 years ago, astronomers looked at stars and planets reflected in shallow bowls of water, through tubes set at the right angles, to measure their positions.
Medieval and early modern
π Explore by field β-
around 1200β Mathematics
Indian numerals reach Europe
From the Arab world the numerals reached Europe and parts of Africa by around 1100 CE; around 1200 the Italian mathematician Fibonacci made the case for Europe to adopt them. Arab scholars called them βHindu numeralsβ.
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13thβ17th centuriesβ Metals and materials
Pure zinc by distillation
The production of pure zinc reached its peak, with a special distillation process used for the first time in the world.
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14th centuryβ Mathematics
Narayana Panditaβs Ganitakaumudi
A massive treatise of mathematics that included important original developments.
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14th centuryβ Mathematics
Madhava and the Kerala School
π KeralaMadhava gave the series expansion for trigonometric functions β a world first β and an exact value of Ο as an infinite series. He and his followers are known as the Kerala School of Astronomy and Mathematics.
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1500π Astronomy
Nilakantha Somayajiβs planetary model
π KeralaA scholar of the Kerala School worked out a planetary model in which Mercury and Venus went round the Sun.
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September 1556π» Computing and communication
The first printing press
π Old GoaSet up by Jesuit missionaries at the Colegio de SΓ£o Paulo β the first printing press in India.
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1727π Engineering, water and towns
Jaipur, a planned city
π JaipurVidyadhar Bhattacharya, appointed by Sawai Jai Singh II, designed the new city on a grid of rectangular blocks, aligned to the cardinal directions, with wide streets, gardens and nine public squares.
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early 18th centuryπ Astronomy
Jantar Mantar observatory
π Jaipur, RajasthanSome 20 giant masonry instruments for observing the sky with the naked eye.
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1780π» Computing and communication
Indiaβs first printed newspaper
The Bengal Gazette β the start, in NCERTβs timeline of communication, of printed news in India.
Modern science
π¬ Modern scientific breakthroughs β-
16 April 1853π Engineering, water and towns
The first passenger train
π Bombay (Mumbai) β ThaneRailways in India began with a passenger train between Bombay and Thane.
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1875π¦ Weather and the Earth
India Meteorological Department set up
After a disastrous cyclone struck Calcutta in 1864 and the monsoon failed in 1866 and 1871, the Government of India brought all meteorological work under one central authority. Its motto: βFrom the sun arises rain.β
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1879β Physics
Electric light arrives
π Calcutta (Kolkata)Electric lighting was demonstrated in Calcutta, the start of electricity in India.
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1881π Engineering, water and towns
Darjeeling Himalayan Railway
π Darjeeling, West BengalThe first hill passenger railway, with bold engineering across mountain terrain.
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1895β Physics
J.C. Bose shows wireless transmission
π CalcuttaJagadish Chandra Bose pioneered wireless transmission using microwaves in the millimetre range; in an experiment in Calcutta he showed that signals could pass through a wall.
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1897β Physics
First commercial electricity: Sidrapong
π Darjeeling, West BengalA 130 kW hydroelectric station began India's first commercial generation of electricity.
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1901β Chemistry
P.C. Ray founds Indiaβs first pharmaceutical company
Prafulla Chandra Ray, βFather of Modern Indian Chemistryβ, founded Bengal Chemicals and Pharmaceuticals β part of the Swadeshi drive to break the British monopoly. He also wrote on the history of chemistry in India.
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27 May 1909π Language, writing and learning
Indian Institute of Science founded
π BangaloreThe Indian Institute of Science came into existence in Bangalore, after Jamsetji Tataβs vision and a Government of India vesting order.
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16 February 1912β Metals and materials
Steel from Jamshedpur
π Jamshedpur, JharkhandThe blast furnace was first blown on 2 December 1911; steel production began weeks later.
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1921β1935π©Ί Medicine and life sciences
R.H. Dastur studies photosynthesis
π Royal Institute of Science, BombayAs head of Botany, Rustom Hormusji Dastur studied how water, temperature and the colour of light affect photosynthesis.
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16 July 1929πΎ Farming and plants
Imperial Council of Agricultural Research founded
Set up following the report of the Royal Commission on Agriculture; it is today the Indian Council of Agricultural Research (ICAR).
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1930π» Computing and communication
Radio broadcasting begins
NCERTβs timeline of communication marks 1930 as the start of All India Radio (AIR) broadcasting in India.
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1930β Physics
C.V. Raman wins the Nobel Prize in Physics
Awarded βfor his work on the scattering of light and for the discovery of the effect named after himβ β the Raman effect.
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1931β Mathematics
Indian Statistical Institute founded
Founded by P.C. Mahalanobis, a scientist and statistician of international repute who later led the team that drafted the Second Five Year Plan.
Space, nuclear and technology
π Space, nuclear and technology milestones β Β· π¬ Modern scientific breakthroughs β-
late 1940sβ’ Nuclear science
Indiaβs nuclear programme begins
Initiated under the guidance of Homi J. Bhabha, to generate atomic energy for peaceful purposes.
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3 August 1954β’ Nuclear science
Department of Atomic Energy set up
Set up under the direct charge of the Prime Minister by a Presidential Order.
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4 August 1956β’ Nuclear science
Apsara, Asiaβs first research reactor
π TrombayApsara achieved criticality and was the first research reactor in Asia to do so.
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21 March 1956π Astronomy
The Indian National Calendar
A Calendar Reform Committee chaired by Meghnad Saha recommended a unified national calendar, adopted from 1 Chaitra 1878 Saka; it follows the general principles of the Surya Siddhanta.
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1957π Engineering, water and towns
Diesel locomotives: the WDM-1
In NCERTβs timeline of Indian trains, the WDM-1 diesel locomotive (1957) follows steam, and the WAM-4 electric locomotive follows in 1970.
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1 March 1958β’ Nuclear science
Atomic Energy Commission set up
An Atomic Energy Commission with full executive and financial powers was set up to plan and expand the atomic energy programme; it makes the policy of the Department of Atomic Energy.
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10 July 1960β’ Nuclear science
The CIRUS research reactor
π TrombayA 40 MWth reactor built with Canada, used for neutron research, testing fuel and making radioisotopes for medicine, agriculture and industry; it trained the engineers of Indiaβs heavy-water reactor programme and ran for 50 years.
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1954β1960π» Computing and communication
TIFRAC: India's first working computer
π TIFR, MumbaiDesigned and built at TIFR β the first electronic digital computer to become operational in India.
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1962π Space
INCOSPAR: Indiaβs space research begins
The Indian National Committee for Space Research was set up by the Government of India, as envisioned by Vikram Sarabhai.
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1960s and 1970sπΎ Farming and plants
The Green Revolution
High-yielding seeds, more irrigation, fertilisers and machines raised food-grain production β especially of wheat and rice β and India became self-sufficient in food. NCERT also notes its costs to soil and groundwater.
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1968π©Ί Medicine and life sciences
Har Gobind Khorana shares the Nobel Prize
Physiology or Medicine, shared with Robert W. Holley and Marshall W. Nirenberg, βfor their interpretation of the genetic code and its function in protein synthesisβ.
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15 August 1969π Space
ISRO is formed
The Indian Space Research Organisation superseded INCOSPAR with an expanded role to harness space technology.
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28 October 1969β’ Nuclear science
Tarapur: Indiaβs first nuclear power station
π Tarapur, MaharashtraUnits 1 and 2 of the Tarapur Atomic Power Station, boiling-water reactors of 160 MWe each, began commercial operation β the first entries in NPCILβs list of nuclear power plants.
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1960s and 1970sπΎ Farming and plants
The White Revolution (Operation Flood)
Alongside the Green Revolution, one of the strategies the Government of India began to improve Indian agriculture.
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1971π©Ί Medicine and life sciences
A bacterium that breaks down oil spills
Ananda Mohan Chakrabarty developed a bacterium that could break down oil spills; the discovery was patented in 1980.
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May 1974β’ Nuclear science
Indiaβs first nuclear test
π PokhranThe first nuclear explosion undertaken by India.
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19 April 1975π Space
Aryabhata, Indiaβs first satellite
π Launched from the Soviet UnionNamed after the astronomer, it was completely designed and fabricated in India and launched by a Soviet rocket.
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7 June 1979π Space
Bhaskara-I: first Indian remote-sensing satellite
π Volgograd launch station (now in Russia)The first experimental remote-sensing satellite built in India; its TV camera images were used in hydrology and forestry.
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18 July 1980π Space
SLV-3 puts Rohini in orbit
π SriharikotaIndiaβs first experimental satellite launch vehicle placed the Rohini satellite RS-1 in orbit, making India the sixth member of an exclusive club of space-faring nations.
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19 June 1981π Space
APPLE, the first Indian communication satellite
π Launched from KourouISROβs first indigenous experimental communication satellite, designed and built in two years in industrial sheds and launched on an Ariane rocket.
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1983β Physics
Subrahmanyan Chandrasekhar shares the Nobel Prize
Physics, shared with William A. Fowler; Chandrasekharβs share was βfor his theoretical studies of the physical processes of importance to the structure and evolution of the starsβ.
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30 August 1983π Space
INSAT-1B
A communication satellite that reached full operational capability in October 1983 and worked into 1990, with all its 4,375 two-way voice circuits in use; it returned around 36,000 Earth images.
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October 1985β’ Nuclear science
Fast Breeder Test Reactor goes critical
π KalpakkamWith the 40 MWth FBTR at the Indira Gandhi Centre for Atomic Research, India entered the small club of countries with fast-breeder technology β the second stage of its three-stage nuclear programme. It runs on an indigenously developed uraniumβplutonium carbide fuel.
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1988π» Computing and communication
C-DAC and the PARAM supercomputer
C-DAC was set up to build supercomputers after the USA denied their import; it has built generations of them, starting with PARAM.
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May 1998β’ Nuclear science
Nuclear tests at Pokhran
π PokhranIndia conducted nuclear explosions at Pokhran.
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2002π©Ί Medicine and life sciences
Mid Day Meal Programme, built on nutrition science
Coluthur Gopalan analysed more than 500 Indian foods and surveyed the nationβs nutrition; his findings of widespread deficiencies led to the Mid Day Meal Programme, now PM POSHAN.
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5 May 2005π Space
Cartosat-1: maps in stereo
π SriharikotaThe first Indian remote-sensing satellite able to take stereo images in orbit, at 2.5 m resolution β used for elevation models and maps. NCERT notes that Cartosat images feed the Bhuvan mapping platform.
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22 October 2008π Space
Chandrayaan-1
π SriharikotaIndia's first mission to the Moon, launched from Sriharikota.
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1 July 2013π Space
IRNSS-1A: Indiaβs own navigation system begins
π SriharikotaThe first of the seven satellites of the Indian Regional Navigation Satellite System, carrying a rubidium atomic clock in its navigation payload.
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5 November 2013π Space
Mars Orbiter Mission
π SriharikotaIndia's first interplanetary mission; ISRO became the fourth space agency to reach Mars orbit.
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28 September 2015π Space
AstroSat, Indiaβs space observatory
π SriharikotaIndiaβs first dedicated space astronomy observatory, with five payloads that observe the same source at once from far ultraviolet to gamma rays.
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25 August 2016π» Computing and communication
UPI: instant digital payments
π IndiaLaunched by NPCI; now the world's largest real-time payment system.
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22 July 2019π Space
Chandrayaan-2
An orbiter, lander and rover to explore the unexplored south pole of the Moon β a significant technological leap for ISRO. It entered lunar orbit on 20 August 2019.
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2019π Engineering, water and towns
Vande Bharat trains
The electric Vande Bharat train β the latest step in NCERTβs timeline of Indian trains, after steam, diesel and electric locomotives.
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December 2022π Astronomy
Hanle Dark Sky Reserve
π Hanle, LadakhThe area around the Himalayan Chandra Telescope β named after Subrahmanyan Chandrasekhar, at one of the highest observatories in the world β was notified as a dark sky reserve.
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2 September 2023π Space
Aditya-L1 studies the Sun
A satellite dedicated to the comprehensive study of the Sun, with seven indigenously developed payloads, placed near the L1 point between the Earth and the Sun.
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23 August 2023π Space
Chandrayaan-3 lands on the Moon
π The MoonA successful soft landing, followed by the rover rolling out onto the lunar surface.
Scientists and scholars
Mains Β· General Studies Paper III: βAchievements of Indians in science & technology; indigenization of technology and developing new technology.β UPSC β
How we check: science milestones are written from NCERT textbooks and official pages (NobelPrize.org, ISRO, DAE, BARC, IISc), and our build fails unless their key phrases are found in the source itself. The Tools & Technology milestones keep their own sources. Dates are as the source gives them; where it gives only a period, so do we. Claims we cannot find in such sources are left out β however often they are repeated elsewhere.