Explore a subject through time

Science timeline

Discoveries and experiments that changed how we understand reality.

39 moments in QuoAnno

Double-helix structure of DNA is published, representing the Science timeline
Double-helix structure of DNA is published · 1953 AD

Reading the timeline

A wider chronology

The history of science is not a straight march from ignorance to certainty. It is a record of observations, instruments, arguments, failed explanations and results that other researchers could test. Discoveries become historical landmarks when they change what questions can be asked or how evidence is interpreted.

A chronological view also reveals that scientific work is collective. Famous publications and experiments depend on earlier methods, shared institutions and contributions that may be recognized only later. QuoAnno places those milestones alongside the wider worlds of medicine, technology and exploration.

What this category covers

Themes to follow

01

Observation

Telescopes, microscopes and measurements that made previously hidden phenomena visible.

02

Experiment

Repeatable tests that challenged explanations and established new evidence.

03

Theory

Models that connected separate observations into broader accounts of nature.

04

Scientific communities

Publication, correspondence, laboratories and institutions through which knowledge was tested.

Across the category

Timeline highlights

8 selected moments
  1. Copernicus publishes De revolutionibus

    The book was published near the end of Copernicus’s life.

  2. Leeuwenhoek observes microorganisms

    Antonie Philips van Leeuwenhoek was a Dutch microbiologist and microscopist in the Golden Age of Dutch art, science and technology.

  3. Faraday discovers electromagnetic induction

    In electromagnetism, Faraday's law of induction describes how a changing magnetic field can induce an electric current in a circuit.

  4. Mendeleev presents an early periodic table

    Mendeleev left gaps for elements that had not yet been discovered.

  5. Max Planck introduces the quantum hypothesis

    In physics, Planck's law describes the spectral density of electromagnetic radiation emitted by a black body in thermal equilibrium at a given temperature T, when there is no net flow of matter or energy between the body and its environment.

  6. Alexander Fleming observes penicillin’s antibacterial effect

    Turning penicillin into a widely usable medicine required later work by several researchers and teams.

  7. Double-helix structure of DNA is published

    Rosalind Franklin’s X-ray diffraction work was crucial to understanding DNA structure.

  8. Plate tectonics becomes a unified scientific theory

    Plate tectonics is the scientific theory that Earth's lithosphere comprises a number of large tectonic plates, which have been slowly moving since 3–4 billion years ago.

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Further reading

These independent reference works and institutions provide broader context. QuoAnno links to them for further reading; the summaries on this page are original and are not copied from those sources.

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