Timeline of scientific discoveries

The timeline below shows the date of publication of possible major scientific theories and discoveries, along with the discoverer. In many cases, the discoveries spanned several years.

4th century BC

• 4th century BC - Mandragora (containing atropin) was described by Theophrastus in the fourth century B.C. for treatment of wounds, gout, and sleeplessness, and as a love potion. By the first century A.D. Dioscorides recognized wine of mandrake as an anaesthetic for treatment of pain or sleeplessness, to be given prior to surgery or cautery.

3rd century BC

• 323–283 BC – Euclid: wrote a series of 13 books on geometry called The Elements
• 287-212 BC - Archimedes of Syracuse: derived an accurate approximation of pi, defined and investigating the spiral bearing his name, and creating a system using exponentiation for expressing very large numbers.
• 280 BC - Aristarchus of Samos: used a heliocentric, heliostatic model

2nd century BC

• 150s BC – Seleucus of Seleucia: discovery of tides being caused by the moon

1st century

• 50 - Pliny the Elder wrote the Natural History

2nd century

• 150s Ptolemy: produced the geocentric model of the solar system.

3rd century

• 200s Galen: produced big contributions to medicine.

9th century

• Al-Kindi (Alkindus): refutation of the theory of the transmutation of metals

10th century

• Muhammad ibn Zakariya al-Razi (Rhazes): refutation of Aristotelian classical elements and Galenic humorism; and discovery of measles and smallpox, and kerosene and distilled petroleum
• 984 - Ibn Sahl accurately describes the optics which became known as Snell's law of refraction

11th century

• 1021 – Ibn al-Haytham's Book of Optics. First use of controlled experiments and reproducibility of its results.
• 1020s – Avicenna's The Canon of Medicine
• 1054 – Various early astronomers observe supernova (modern designation SN 1054), later correlated to the Crab Nebula.
• Shen Kuo: Discovers the concepts of true north and magnetic declination. In addition, he develops the first theory of Geomorphology.

12th century

• 1121 – Al-Khazini: variation of gravitation and gravitational potential energy at a distance; the decrease of air density with altitude
• Ibn Bajjah (Avempace): discovery of reaction (precursor to Newton's third law of motion)
• Hibat Allah Abu'l-Barakat al-Baghdaadi (Nathanel): relationship between force and acceleration (a vague foreshadowing of a fundamental law of classical mechanics and a precursor to Newton's second law of motion)
• Averroes: relationship between force, work and kinetic energy

13th century

• 1220–1235 – Robert Grosseteste: rudimentals of the scientific method (see also: Roger Bacon)
• 1242 – Ibn al-Nafis: pulmonary circulation and circulatory system
• Theodoric of Freiberg: correct explanation of rainbow phenomenon
• William of Saint-Cloud: pioneering use of camera obscura to view solar eclipses

14th century

• Before 1327 – William of Ockham: Occam's Razor
• Oxford Calculators: the mean speed theorem
• Jean Buridan: theory of impetus
• Nicole Oresme: discovery of the curvature of light through atmospheric refraction

15th century

• 1494 - Luca Pacioli: first codification of the double-entry bookkeeping system, which slowly developed in previous centuries

16th century

• 1543 – Nicolaus Copernicus: heliocentric model
• 1543 – Vesalius: pioneering research into human anatomy
• 1552 – Michael Servetus: early research in Europe into pulmonary circulation
• 1570s – Tycho Brahe: detailed astronomical observations
• 1600 – William Gilbert: Earth's magnetic field

17th century

• 1608 - Invention of the telescope
• 1609 – Johannes Kepler: first two laws of planetary motion
• 1610 – Galileo Galilei: Sidereus Nuncius: telescopic observations
• 1614 – John Napier: use of logarithms for calculation
• 1619 - Johannes Kepler: third law of planetary motion
• 1628 – Willebrord Snellius: the law of refraction also known as Snell's law
• 1628 – William Harvey: Blood circulation
• 1638 - Galileo Galilei: laws of falling body
• 1643 – Evangelista Torricelli invents the mercury barometer
• 1662 – Robert Boyle: Boyle's law of ideal gas
• 1665 – Philosophical Transactions of the Royal Society first peer reviewed scientific journal published.
• 1665 - Robert Hooke: discovers the cell
• 1668 – Francesco Redi: disproved idea of spontaneous generation
• 1669 – Nicholas Steno: Proposes that fossils are organic remains embedded in layers of sediment, basis of stratigraphy
• 1669 – Jan Swammerdam: epigenesis in insects
• 1672 – Sir Isaac Newton: discovers that white light is a spectrum of a mixture of distinct coloured rays
• 1673 - Christiaan Huygens: first study of oscillating system and design of pendulum clocks
• 1675 – Leibniz, Newton: infinitesimal calculus
• 1675 – Anton van Leeuwenhoek: observes microorganisms by microscope
• 1676 – Ole Rømer: first measurement of the speed of light
• 1687 – Sir Isaac Newton: classical mathematical description of the fundamental force of universal gravitation and the three physical laws of motion

18th century

• 1745 – Ewald Jürgen Georg von Kleist first capacitor, the Leyden jar
• 1750 – Joseph Black: describes latent heat
• 1751 – Benjamin Franklin: Lightning is electrical
• 1755 - Immanuel Kant: Gaseous Hypothesis in Universal Natural History and Theory of Heaven
• 1761 – Mikhail Lomonosov: discovery of the atmosphere of Venus
• 1763 – Thomas Bayes: publishes the first version of Bayes' theorem, paving the way for Bayesian probability
• 1771 – Charles Messier: Publishes catalogue of astronomical objects (Messier Objects) now known to include galaxies, star clusters, and nebulae.
• 1778 – Antoine Lavoisier (and Joseph Priestley): discovery of oxygen leading to end of Phlogiston theory
• 1781 – William Herschel announces discovery of Uranus, expanding the known boundaries of the solar system for the first time in modern history
• 1785 – William Withering: publishes the first definitive account of the use of foxglove (digitalis) for treating dropsy
• 1787 – Jacques Charles: Charles's law of ideal gas
• 1789 – Antoine Lavoisier: law of conservation of mass, basis for chemistry, and the beginning of modern chemistry
• 1796 – Georges Cuvier: Establishes extinction as a fact
• 1796 – Edward Jenner: small pox historical accounting
• 1796 – Hanaoka Seishū: develops general anaesthesia
• 1800 – Alessandro Volta: discovers electrochemical series and invents the battery
• 1800 – William Herschel discovers infrared radiation.

19th century

• 1802 – Jean-Baptiste Lamarck: teleological evolution
• 1805 – John Dalton: Atomic Theory in (Chemistry)
• 1820 – Hans Christian Ørsted discovers that a current passed through a wire will deflect the needle of a compass, establishing a deep relationship between electricity and magnetism (electromagnetism).
• 1821 – Thomas Johann Seebeck is the first to observe a property of semiconductors.
• 1824 – Carnot: described the Carnot cycle, the idealized heat engine
• 1827 – Georg Ohm: Ohm's law (Electricity)
• 1827 – Amedeo Avogadro: Avogadro's law (Gas law)
• 1828 – Friedrich Wöhler synthesized urea, destroying vitalism
• 1830 - Nikolai Lobachevsky created Non-Euclidean geometry
• 1831 – Michael Faraday discovers electromagnetic induction
• 1833 – Anselme Payen isolates first enzyme, diastase
• 1838 – Matthias Schleiden: all plants are made of cells
• 1838 – Friedrich Bessel: first successful measure of stellar parallax (to star 61 Cygni)
• 1842 – Christian Doppler: Doppler effect
• 1843 – James Prescott Joule: Law of Conservation of energy (First law of thermodynamics), also 1847 – Helmholtz, Conservation of energy
• 1846 – Johann Gottfried Galle and Heinrich Louis d'Arrest: discovery of Neptune
• 1848 – Lord Kelvin: absolute zero
• 1858 – Rudolf Virchow: cells can only arise from pre-existing cells
• 1859 – Charles Darwin and Alfred Wallace: Theory of evolution by natural selection
• 1861 - Louis Pasteur: Germ theory
• 1861 - John Tyndall: Experiments in Radiant Energy that reinforced the Greenhouse Effect
• 1864 – James Clerk Maxwell: Theory of electromagnetism
• 1865 – Gregor Mendel: Mendel's laws of inheritance, basis for genetics
• 1865 – Rudolf Clausius: Definition of Entropy
• 1869 – Dmitri Mendeleev: Periodic table
• 1871 – Lord Rayleigh: Diffuse sky radiation (Rayleigh scattering) explains why sky appears blue
• 1873 – Johannes Diderik van der Waals: was one of the first to postulate an intermolecular force: the van der Waals force.
• 1873 – Frederick Guthrie discovers thermionic emission.
• 1873 - Willoughby Smith discovers photoconductivity.
• 1875 – William Crookes invented the Crookes tube and studied cathode rays
• 1876 – Josiah Willard Gibbs founded chemical thermodynamics, the phase rule
• 1877 – Ludwig Boltzmann: Statistical definition of entropy
• 1880 – Pierre Curie and Jacques Curie: Piezoelectricity
• 1884 – Jacobus Henricus van 't Hoff: discovered the laws of chemical dynamics and osmotic pressure in solutions (in his work "Etudes de dynamique chimique").
• 1887 – Albert A. Michelson and Edward W. Morley: lack of evidence for the aether
• 1888 – Friedrich Reinitzer discovers liquid crystals.
• 1892 – Dmitri Ivanovsky discovers for the first time a virus
• 1895 – Wilhelm Conrad Röntgen discovers x-rays
• 1896 – Henri Becquerel discovers radioactivity
• 1896 - Svante Arrhenius derives the basic principles of the greenhouse effect.
• 1897 – J.J. Thomson discovers the electron in cathode rays
• 1898 – Martinus Beijerinck: concluded a virus infectious—replicating in the host—and thus not a mere toxin and gave it the name 'virus
• 1898 – J.J. Thomson proposed the Plum pudding model of an atom
• 1898 – Adam jasper was discovered

20th century

• 1905 – Albert Einstein: theory of special relativity, explanation of Brownian motion, and photoelectric effect
• 1906 – Walther Nernst: Third law of thermodynamics
• 1907 – Alfred Bertheim: Arsphenamine, the first modern chemotherapeutic agent
• 1909 – Fritz Haber: Haber Process for industrial production of ammonia
• 1909 – Robert Andrews Millikan: conducts the oil drop experiment and determines the charge on an electron
• 1910 – Williamina Fleming: the first white dwarf, 40 Eridani B
• 1911 – Ernest Rutherford: Atomic nucleus
• 1911 – Heike Kamerlingh Onnes: Superconductivity
• 1912 – Alfred Wegener: Continental drift
• 1912 – Max von Laue : x-ray diffraction
• 1912 – Vesto Slipher : galactic redshifts
• 1912 – Henrietta Swan Leavitt: Cepheid variable period luminosity relation
• 1913 – Henry Moseley: defined atomic number
• 1913 – Niels Bohr: Model of the atom
• 1915 – Albert Einstein: theory of general relativity – also David Hilbert
• 1915 – Karl Schwarzschild: discovery of the Schwarzschild radius leading to the identification of black holes
• 1918 – Emmy Noether: Noether's theorem – conditions under which the conservation laws are valid
• 1920 – Arthur Eddington: Stellar nucleosynthesis
• 1922 – Frederick Banting, Charles Best, James Collip, John Macleod: isolation and production of insulin to control diabetes
• 1924 – Wolfgang Pauli: quantum Pauli exclusion principle
• 1924 – Edwin Hubble: the discovery that the Milky Way is just one of many galaxies
• 1925 – Erwin Schrödinger: Schrödinger equation (Quantum mechanics)
• 1925 – Cecilia Payne-Gaposchkin: Discovery of the composition of the Sun and that Hydrogen is the most abundant element in the Universe
• 1927 – Werner Heisenberg: Uncertainty principle (Quantum mechanics)
• 1927 – Georges Lemaître: Theory of the Big Bang
• 1928 – Paul Dirac: Dirac equation (Quantum mechanics)
• 1929 – Edwin Hubble: Hubble's law of the expanding universe
• 1928 – Alexander Fleming: Penicillin, the first beta-lactam antibiotic
• 1929 – Lars Onsager's reciprocal relations, a potential fourth law of thermodynamics
• 1930 – Subrahmanyan Chandrasekhar discovers his eponymous limit of the maximum mass of a white dwarf star
• 1932 – James Chadwick: Discovery of the neutron
• 1932 – Karl Guthe Jansky discovers the first astronomical radio source, Sagittarius A
• 1932 - Ernest Walton and John Cockcroft: Nuclear fission by proton bombardment
• 1934 – Enrico Fermi: Nuclear fission by neutron irradiation
• 1934 – Clive McCay: Calorie restriction extends the maximum lifespan of another species
• 1938 – Otto Hahn, Lise Meitner and Fritz Strassmann: Nuclear fission of heavy nuclei
• 1938 – Isidor Rabi: Nuclear magnetic resonance
• 1943 – Oswald Avery proves that DNA is the genetic material of the chromosome
• 1945 - Howard Florey Mass production of penicillin
• 1947 – William Shockley, John Bardeen and Walter Brattain invent the first transistor
• 1948 – Claude Elwood Shannon: 'A mathematical theory of communication' a seminal paper in Information theory.
• 1948 – Richard Feynman, Julian Schwinger, Sin-Itiro Tomonaga and Freeman Dyson: Quantum electrodynamics
• 1951 – George Otto Gey propagates first cancer cell line, HeLa
• 1952 – Jonas Salk: developed and tested first polio vaccine
• 1952 - Frederick Sanger: demonstrated that proteins are sequences of amino acids
• 1953 – James Watson, Francis Crick, Maurice Wilkins and Rosalind Franklin: helical structure of DNA, basis for molecular biology
• 1962 – Riccardo Giacconi and his team discover the first cosmic x-ray source, Scorpius X-1
• 1963 – Lawrence Morley, Fred Vine, and Drummond Matthews: Paleomagnetic stripes in ocean crust as evidence of plate tectonics (Vine-Matthews-Morley hypothesis).
• 1964 – Murray Gell-Mann and George Zweig: postulates quarks leading to the standard model
• 1964 – Arno Penzias and Robert Woodrow Wilson: detection of CMBR providing experimental evidence for the Big Bang
• 1965 – Leonard Hayflick: normal cells divide only a certain number of times: the Hayflick limit
• 1967 – Jocelyn Bell Burnell and Antony Hewish discover first pulsar
• 1967 – Vela nuclear test detection satellites discover the first gamma-ray burst
• 1971 – Place cells in the brain are discovered by John O'Keefe
• 1974 – Russell Alan Hulse and Joseph Hooton Taylor, Jr. discover indirect evidence for gravitational wave radiation in the Hulse–Taylor binary
• 1977 - Frederick Sanger sequences the first DNA genome of an organism using Sanger sequencing
• 1980 – Klaus von Klitzing discovered the Quantum Hall Effect.
• 1982 – Becker et al. discover the first millisecond pulsar
• 1983 – Kary Mullis invents the polymerase chain reaction, a key discovery in molecular biology.
• 1986 – Karl Müller and Johannes Bednorz: Discovery of High-temperature superconductivity.
• 1988 – Bart van Wees and colleagues at TU Deflt and Philips Research discovered the quantized conductance in a two-dimensional electron gas.
• 1992 - Aleksander Wolszczan and Dale Frail observe the first pulsar planets (this was the first confirmed discovery of planets outside the Solar System)
• 1994 - Andrew Wiles proves Fermat's Last Theorem
• 1995 – Michel Mayor and Didier Queloz definitively observe the first extrasolar planet around a main sequence star
• 1995 - Eric Cornell, Carl Wieman and Wolfgang Ketterle attained the first Bose-Einstein Condensate with atomic gases, so called fifth state of matter at an extremely low temperature.
• 1996 – Roslin Institute: Dolly the sheep was cloned.
• 1997 – CDF and DØ experiments at Fermilab: Top quark.
• 1998 – Supernova Cosmology Project and the High-Z Supernova Search Team: discovery of the accelerated expansion of the Universe / Dark Energy.
• 2000 – The Tau neutrino is discovered by the DONUT collaboration

21st century

• 2001 – The first draft of the Human Genome Project is published.
• 2002 - Cheese is declared the greatest food by Albert Einstein when he came back from the dead.
• 2003 – Grigori Perelman presents proof of the Poincaré Conjecture.
• 2004 – Andre Geim and Konstantin Novoselov isolated graphene, a monolayer of carbon atoms, and studied its quantum electrical properties.
• 2005 – Grid cells in the brain are discovered by Edvard Moser and May-Britt Moser.
• 2010 – The first Self-Replicating, Synthetic Bacterial Cells are Constructed.
• 2010 - The Neanderthal Genome Project presented preliminary genetic evidence that interbreeding did likely take place and that a small but significant portion of Neanderthal admixture is present in modern non-African populations.
• 2012 - Higgs boson is discovered at CERN (confirmed to 99.999% certainty)
• 2012 - Photonic molecules are discovered at MIT
• 2014 - Exotic hadrons are discovered at the LHCb
• 2015 - Traces of liquid water discovered on Mars
• 2016 - The LIGO team detected gravitational waves from a black hole merger.
• 2017 - Gravitational wave signal GW170817 was observed by the LIGO/Virgo collaboration. This was the first instance of a gravitational wave event that was observed to have a simultaneous electromagnetic signal when space telescopes like Hubble observed lights coming from the event, thereby marking a significant breakthrough for multi-messenger astronomy.

External links

• Science Timeline