Timeline of scientific discoveries

4th century BCE

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

3rd century BCE

323–283 BCE – Euclid: wrote a series of 13 books on geometry called The Elements

280 BCE - Aristarchus of Samos: used a heliocentric, heliostatic model

2nd century BCE

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

2nd century

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

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

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

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 – Marie Curie discovers polonium, radium, and coins the term "radioactivity"

1900 – Max Planck: Planck's law of black body radiation, basis for quantum theory

20th century

1901 – Annie Jump Cannon: stellar classification

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

1934 – Clive McCay: Calorie restriction extends the maximum lifespan of another species

1938 – Otto Hahn, Lise Meitner and Fritz Strassmann: Nuclear fission

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

1953 – Crick and Watson: 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

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

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.

2003 - Grigori Perelman presents proof of the Poincaré Conjecture.

2005 – Grid cells in the brain are discovered by Edvard Moser and May-Britt Moser.

2006 - Shinya Yamanaka generates first induced pluripotent stem cells

2007 – The first fast radio burst is discovered in archival data taken in 2001 by Parkes Radio Telescope

2010 – J. Craig Venter Institute creates the first synthetic genome for a bacterial cell.

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.