~600 BCE — Thales of Miletus studies magnetism and static electricity
Description: The word “electricity” comes from the Greek name for amber, which Thales experimented with.
Physics, chemistry, astronomy, biology, medicine and mathematics — from Babylonian tablets to the Higgs boson. Each of the 200 events opens on click. All lanes are on by default. Click a chip to hide a discipline; click again to bring it back. “All disciplines” turns every lane on. Zoom in (the + / − buttons, or Ctrl + mouse wheel) and event names appear on the lanes.
Description: The word “electricity” comes from the Greek name for amber, which Thales experimented with.
Description: Babylonian observational tablets became the foundation for many later astronomical systems, including the Greek one.
Description: The Ebers Papyrus contains more than 700 recipes and formulas, including descriptions of tumors.
Description: Plimpton 322 shows that the Babylonians knew the Pythagorean theorem more than a thousand years before Pythagoras.
Description: The Rhind Papyrus is essentially the oldest known mathematics textbook, including problems and their solutions.
Description: The word “atom” itself comes from the Greek for “indivisible” — that is how Democritus pictured the smallest particle of matter.
Description: According to legend, Archimedes made the discovery in his bath and ran into the street shouting “Eureka!”
Description: The word “alchemy” itself is thought to come from the Arabic al-kīmiyā, which in turn goes back to an ancient name for Egypt.
Description: Thales’s eclipse prediction, according to legend, halted a battle between the Lydians and the Medes.
Description: Aristotle’s geocentric model dominated European science for nearly two millennia.
Description: Eratosthenes’s calculation differs from the modern value of Earth’s circumference by only a few percent.
Description: Hipparchus’s catalog contained more than 800 stars, with their brightness indicated.
Description: Aristotle’s work describes and classifies more than 500 species of animals.
Description: Theophrastus is often called the “father of botany” — he described more than 500 plant species.
Description: Hippocrates is considered the author of an oath that, in modified form, medical school graduates still take today.
Description: Thales, according to tradition, proved the theorem that an angle inscribed in a semicircle is a right angle.
Description: The Pythagoreans believed that the entire universe is structured on numerical relationships.
Description: Euclid’s Elements remained the model of mathematical proof for more than two thousand years and is one of the most published books in history.
Description: Archimedes calculated π to several digits without having a decimal number system.
Description: The Almagest remained the principal astronomical textbook of Europe and the Arab world for more than 1,400 years.
Description: The Almagest remained the principal astronomical work of Europe and the Islamic world for more than 1,400 years.
Description: Indian astronomy developed largely independently of the Greek and Arabic traditions.
Description: Galen’s writings remained Europe’s chief medical authority for more than 1,300 years, despite numerous errors.
Description: Diophantus’s Arithmetica later inspired Fermat to formulate his famous Last Theorem.
Description: In the West, Ibn al-Haytham was known as Alhazen — his work was translated into Latin and influenced Kepler and Newton.
Description: In the West, Jabir ibn Hayyan was known as Geber — the chemical term “Geberism” was later named in his honor.
Description: Al-Sufi’s observations anticipated telescopic discoveries of nebulae by nearly seven centuries.
Description: The remnant of that 1054 supernova is known today as the Crab Nebula.
Description: Ibn Sina’s Canon remained a required textbook in European universities until the 17th century.
Description: Brahmagupta was one of the first mathematicians to give a rigorous definition of operations with the number zero.
Description: The word “algebra” itself comes from the title of his treatise, al-jabr.
Description: Zero as a digit in its own right reached Europe through this numeral system.
Description: Albertus Magnus was probably one of the first to isolate pure arsenic as a distinct substance.
Description: Ulugh Beg’s observatory could measure star positions with an accuracy unmatched for centuries.
Description: Fibonacci introduced Hindu–Arabic numerals to Europe through a book devoted mainly to practical problems of trade.
Description: Copernicus’s work was published shortly before his death and initially attracted little attention from the Church.
Description: The legend of dropping balls from the Leaning Tower of Pisa is probably embellished, but the essence of the experiment is confirmed by Galileo’s other work.
Description: Copernicus’s work was published shortly before the author’s death and at first provoked little opposition from the Church.
Description: Tycho Brahe’s observation proved that the heavens are not unchanging, as had been believed since Aristotle.
Description: Vesalius’s work corrected many anatomical errors inherited from Galen.
Description: Cardano partly borrowed the formula for cubic equations from another mathematician, sparking one of the first major disputes over scientific priority.
Description: Kepler derived his laws by processing Tycho Brahe’s vast body of observational data.
Description: Galileo was summoned before the Inquisition for these discoveries — they contradicted the official geocentric picture of the world.
Description: The book was written as a dialogue — a genre Galileo used later as well, with more tragic consequences.
Description: Boyle’s law became one of the first quantitative laws in the history of physics.
Description: Many historians consider Newton’s Principia the most influential scientific book in history.
Description: In this book Newton first described in detail the dispersion of light through a prism.
Description: The title of Boyle’s book literally means “the chemist who doubts [old theories].”
Description: The inventor of the telescope is not known with certainty — Hans Lippershey was the first to apply for a patent.
Description: Kepler’s laws were the first to describe planetary orbits as elliptical rather than circular.
Description: Galileo’s discoveries provided the first observational evidence for the heliocentric system.
Description: Huygens discerned Saturn’s rings thanks to a more powerful telescope he had built himself.
Description: Newton’s law of gravitation explained the motion of the planets by the same principles as the fall of an apple on Earth.
Description: Hooke was the first to use the word “cell,” comparing the structures he saw to monks’ cells.
Description: Redi’s experiment with covered and uncovered jars of meat became one of the first examples of a controlled scientific experiment.
Description: Leeuwenhoek was the first in history to see unicellular organisms under a microscope, calling them “animalcules.”
Description: Harvey calculated that the heart pumps an enormous volume of blood in a day — far too much for blood simply to be “consumed,” as had previously been thought.
Description: Leeuwenhoek discovered bacteria two centuries before scientists linked microbes to disease.
Description: Napier’s logarithms greatly simplified complex calculations long before calculators existed.
Description: Descartes’s analytic geometry first linked algebra and geometry through a coordinate system that now bears his name.
Description: The Pascal–Fermat correspondence arose from a practical question — how to divide stakes fairly in an interrupted game of chance.
Description: Newton developed much of the calculus during a forced isolation caused by a plague epidemic in Cambridge.
Description: The priority dispute between Newton and Leibniz over the invention of calculus lasted for decades and divided mathematicians in Britain and continental Europe.
Description: The modern notation of calculus (dx, dy, the integral) comes from Leibniz’s system, not Newton’s.
Description: Engineers still use Bernoulli’s equations when calculating an airplane wing.
Description: The unit of electric charge — the coulomb — is named in his honor.
Description: Cavendish’s experiment is sometimes called “weighing the Earth.”
Description: Carbon dioxide was the first distinct “kind of air” isolated and described in chemistry.
Description: Priestley and Scheele made the discovery almost simultaneously and independently of each other, a common occurrence in 18th-century science.
Description: The phlogiston theory dominated chemistry for nearly a century before it was finally overturned.
Description: Lavoisier’s law of conservation of mass is often called the beginning of modern scientific chemistry.
Description: The comet named after Halley returns to Earth roughly once every 76 years.
Description: The discovery of Uranus was the first expansion of the Solar System beyond the planets known since antiquity.
Description: Linnaeus’s system, including the familiar division into genera and species, is still used by biologists with virtually no change.
Description: Lind found that citrus fruits cure scurvy — long before vitamin C itself was discovered.
Description: The word “vaccine” comes from the Latin name for the cow — Jenner used the cowpox virus.
Description: The Königsberg bridge problem launched an entire field of mathematics — graph theory.
Description: Gauss proved the theorem in his doctoral dissertation when he was only 21 years old.
Description: Volta’s battery was the first source of continuous electric current in history.
Description: Ørsted’s discovery was almost accidental — a compass needle twitched during a demonstration for students.
Description: The unit of electrical capacitance — the farad — is named after Faraday, who had no formal mathematical education.
Description: The second law of thermodynamics is sometimes called the law that explains why time flows only forward.
Description: Maxwell’s equations were the first to show mathematically that light is an electromagnetic wave.
Description: The negative result of this experiment is considered one of the key precursors of the theory of relativity.
Description: Röntgen named the radiation he discovered “X-rays” because of its unknown nature — that is still the English name today.
Description: The discovery of the electron first showed that the atom is not an indivisible particle.
Description: Dalton derived atomic theory by studying the proportions in which elements combine with one another.
Description: Avogadro’s law explained why equal volumes of different gases under the same conditions contain the same number of molecules.
Description: Döbereiner’s work anticipated the periodic system half a century before Mendeleev.
Description: The synthesis of urea is considered the moment when organic chemistry ceased to be regarded as a domain beyond laboratory reproduction.
Description: The laws of electrolysis became the foundation of modern electrochemistry and the industrial production of metals.
Description: The name “ozone” comes from the Greek word for “smelling” — the gas does indeed have a characteristic sharp odor.
Description: Perkin’s dye was discovered by accident, during a failed attempt to synthesize a malaria drug.
Description: Spectral analysis made it possible for the first time to determine the chemical composition of stars, including the Sun.
Description: Mendeleev left empty spaces in the table and predicted the properties of as-yet-undiscovered elements — the predictions were confirmed.
Description: Marie Curie became the first person to receive Nobel Prizes in two different scientific fields.
Description: Bessel’s parallax method made it possible for the first time to measure actual distances to stars.
Description: The planet Neptune was computed mathematically before it was first seen through a telescope.
Description: Spectral analysis of stars showed that they are composed of the same chemical elements as Earth.
Description: The term “biology” was introduced independently by several European scientists.
Description: Lamarck incorrectly believed that traits acquired during life could be passed on to offspring.
Description: Cell theory holds that all living organisms are composed of cells — the basic units of life.
Description: Mendel conducted his experiments in a monastery garden, crossing more than 28,000 pea plants.
Description: Darwin delayed publishing the theory for nearly 20 years, fearing public reaction.
Description: Pasteur’s experiments finally buried the idea of spontaneous generation, which had dominated for millennia.
Description: During Mendel’s lifetime his work went almost unnoticed by the scientific community.
Description: Miescher isolated DNA from the cell nuclei of pus-soaked bandages left over from operations.
Description: The word “stethoscope” comes from the Greek words for “chest” and “to look.”
Description: Before anesthesia, operations were performed with the patient conscious, often restrained by physical force.
Description: Semmelweis’s contemporaries ridiculed him, and his idea was recognized only after his death.
Description: Snow identified the source of the epidemic by mapping cases in London — one of the first examples of medical statistics.
Description: Lister developed antisepsis independently of whether he knew of Pasteur’s germ theory at the time.
Description: Koch formulated criteria for determining that a given microorganism causes a specific disease.
Description: Pasteur tested the vaccine on a boy bitten by a rabid dog, even though he had no medical degree.
Description: Röntgen made the first medical radiograph in history — of his own wife’s hand.
Description: Gauss is called the “prince of mathematicians” — according to legend, as a child he instantly added the numbers from 1 to 100.
Description: Non-Euclidean geometry showed that Euclid’s parallel postulate is not the only possibility.
Description: Boolean algebra became the foundation of the binary logic on which all modern computers are built.
Description: The Riemann hypothesis remains one of the most important unsolved problems in modern mathematics.
Description: Cantor’s set theory met such fierce resistance from colleagues that it may have affected his mental health.
Description: Planck introduced the quantum reluctantly, regarding it more as a mathematical device than a physical reality.
Description: Special relativity was published when Einstein was only 26 years old.
Description: Rutherford compared his discovery to firing a cannonball at tissue paper and finding something solid inside.
Description: General relativity predicted the curvature of spacetime — experimentally confirmed as early as 1919.
Description: The uncertainty principle states that one cannot know both the position and the velocity of a particle exactly at the same time.
Description: The discovery of the neutron explained why atomic nuclei are heavier than one would expect from the number of protons alone.
Description: This discovery became the foundation of both nuclear power and nuclear weapons.
Description: Haber’s ammonia synthesis made cheap fertilizers possible, but the same method was used to produce explosives.
Description: Moseley’s work explained anomalies in Mendeleev’s table, which had been based on atomic weight alone.
Description: Lewis’s theory introduced the now-familiar “dots” for representing electron pairs in chemical formulas.
Description: Deuterium is almost twice as heavy as ordinary hydrogen because of an extra neutron in the nucleus.
Description: Nylon became the first fully synthetic fiber produced on an industrial scale.
Description: Leavitt’s relation became the basis of the method for measuring distances to remote galaxies.
Description: General relativity predicted an effect that did not exist in Newtonian physics.
Description: The eclipse expedition was led by Arthur Eddington, who made Einstein’s theory world-famous.
Description: Before Hubble’s discovery, the entire visible universe was thought to be confined to the Milky Way.
Description: The discovery of the expanding universe became the foundation of the Big Bang theory.
Description: Mendel’s work was rediscovered independently by three scientists in the same year.
Description: The word “genetics” comes from a Greek root meaning “origin.”
Description: Morgan conducted experiments on Drosophila fruit flies — they have remained one of biology’s chief model organisms ever since.
Description: Griffith’s experiment first showed that some substance can transfer hereditary traits between bacteria.
Description: The concept of the ecosystem united living organisms and their habitat into a single system of study.
Description: The term “molecular biology” was coined by a physicist, not a biologist — Warren Weaver.
Description: Avery experimentally proved that the carrier of heredity is DNA, not proteins as previously thought.
Description: Landsteiner received the Nobel Prize for a discovery that made blood transfusion a safe procedure.
Description: Before the discovery of insulin, a diagnosis of type 1 diabetes mellitus almost always meant death within a few years.
Description: Fleming noticed the effect of penicillin by accident — on a mold-contaminated dish that had spoiled an experiment.
Description: Kolff’s machine was assembled from makeshift materials, including tin cans and a washing machine.
Description: WHO was created as a specialized agency of the newly formed United Nations.
Description: Of Hilbert’s 23 problems, some have been solved and some remain open to this day.
Description: Gödel’s theorems showed that in any sufficiently complex mathematical system there are statements that can be neither proved nor disproved.
Description: The Turing machine is a theoretical model that became the foundation of computability theory and modern computers.
Description: The transistor replaced bulky vacuum tubes and became the foundation of all modern electronics.
Description: The particle was jokingly nicknamed the “God particle” — Higgs himself was unenthusiastic about the nickname.
Description: The image of atoms was obtained by field ion microscopy — long before the invention of the scanning tunneling microscope.
Description: The DNA structure discovered by Watson and Crick used X-ray images by Rosalind Franklin, whose contribution was long undervalued.
Description: Carson’s book is considered one of the main catalysts of the modern environmental movement.
Description: Mass spectrometry makes it possible to determine the composition of a substance from the mass and charge of individual ions.
Description: Fullerenes were named after the architect Buckminster Fuller for their resemblance to the spherical domes he designed.
Description: Carbon nanotubes are many times stronger than steel at a far lower density.
Description: The antihydrogen atom existed for only a tiny fraction of a second before annihilating.
Description: The satellite launch marked the beginning of the space age and the space race.
Description: The cosmic microwave background was discovered by accident — engineers first took the signal for interference from pigeon droppings in the antenna.
Description: The first to set foot on the Moon were the astronauts of the Apollo 11 mission in 1969.
Description: Despite a mirror defect at launch, Hubble after repair became one of the most productive telescopes in history.
Description: Since 1995, scientists have confirmed the existence of thousands of exoplanets.
Description: The double-helix model was built in large part thanks to X-ray images by Rosalind Franklin.
Description: Deciphering the genetic code showed that it is virtually universal for all living organisms on Earth.
Description: The discovery of restriction enzymes gave scientists “molecular scissors” for working with DNA.
Description: The first recombinant DNA combined genes from entirely different species of organisms.
Description: At the Asilomar conference, scientists voluntarily paused some experiments until safety rules were developed.
Description: Sanger sequencing remained the principal method of DNA sequencing for nearly 30 years.
Description: Mullis said the idea for the method came to him during a nighttime drive along a California highway.
Description: The Human Genome Project brought together scientists from six countries and cost several billion dollars.
Description: Dolly lived only six and a half years — less than the average lifespan of sheep of her breed.
Description: The Salk vaccine was tested in the largest medical study in U.S. history up to that time.
Description: The first kidney transplant was performed between identical twins, which solved the problem of rejection.
Description: Barnard’s first heart-transplant patient lived only 18 days after the operation.
Description: The birth of the “test-tube baby” sparked intense ethical debates that continue in various forms today.
Description: Smallpox remains the only human infectious disease fully eradicated by medical effort.
Description: The first cases of AIDS were described as a rare cluster of unusual infections in several patients.
Description: Combination therapy first turned HIV infection from a death sentence into a manageable chronic disease.
Description: The first approved gene-therapy protocol was applied to a four-year-old girl with a rare immune disorder.
Description: Shannon’s information theory introduced the “bit” as a unit of information.
Description: The proof of the four color theorem required a computer to check thousands of cases — many mathematicians at first refused to accept such a proof as “real.”
Description: Wiles worked on the proof in secret for nearly seven years before presenting it to the public.
Description: Confirmation of the Higgs boson completed nearly half a century of searching for the last missing particle of the Standard Model.
Description: Sequencing the human genome took more than ten years of international collaboration.
Description: Graphene is a material one carbon atom thick, with record strength and electrical conductivity.
Description: The synthesized superheavy elements exist for only fractions of a second before decaying.
Description: The discovery of gravitational waves confirmed the last of the key predictions of Einstein’s general theory of relativity.
Description: The black-hole image was produced by combining data from telescopes around the world into a single virtual telescope the size of Earth.
Description: Completing the genome sequence took several years longer and cost many times more than originally expected.
Description: CRISPR was discovered as part of the bacterial immune system that protects bacteria from viruses.
Description: The 2022 final version of the genome was the first to fill previously “empty” and hard-to-read stretches of DNA.
Description: The name SARS stands for “severe acute respiratory syndrome.”
Description: The COVID-19 pandemic was the first pandemic of this scale in the age of global air travel.
Description: mRNA vaccines were developed faster than any vaccine in the history of medicine — thanks to decades of prior research on the technology.
Description: For solving the Poincaré conjecture Perelman was awarded a million-dollar prize, which he declined.
Description: AI systems already help mathematicians find counterexamples and suggest directions for new proofs.