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A WORLD OF SMALL DISCOVERIES

Days that made a difference.

38 illustrated stories · growing daily
A laboratory researcher handles a clear vial while colleagues study results beside midcentury laboratory equipment.Science & discoveries

Salk polio vaccine field-trial results announced in 1955

On 12 April 1955, Thomas Francis Jr. announced the results of the large trial of Jonas Salk’s inactivated polio vaccine. Evidence that vaccination could prevent paralytic disease transformed public expectations, while leaving the work of safe production and widespread delivery ahead.

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An Egyptian excavation worker brushes sand from a rock-cut step while an archaeologist watches from behind.Science & discoveries

The first step to Tutankhamun’s tomb is uncovered

On 4 November 1922, excavation in Egypt’s Valley of the Kings revealed a rock-cut step leading toward Tutankhamun’s tomb. The discovery began a sequence of clearance and investigation rather than an immediate encounter with the burial treasures.

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Marie Curie examines samples beside measuring apparatus while Pierre Curie and Gustave Bémont confer in a period workshop.Science & discoveries

The announcement of radium on 26 December 1898

Pierre Curie, Marie Curie and Gustave Bémont announced evidence for radium in a paper dated 26 December 1898. Radioactivity measurements and a previously unknown spectral line revealed an element present in minute quantities among chemically similar material.

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King Mongkut and observers stand beside a brass telescope under a coastal pavilion during a total eclipse.Science & discoveries

King Mongkut’s Observation of the 1868 Wa Ko Solar Eclipse

On 18 August 1868, King Mongkut of Siam observed a total solar eclipse at Wa Ko. His advance prediction made the expedition a public demonstration of mathematical astronomy, later commemorated by Thailand’s National Science Day.

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Maria Mitchell observes the night sky through a brass telescope above Nantucket rooftops, with a notebook nearby.Science & discoveries

Maria Mitchell’s comet discovery on 1 October 1847

Maria Mitchell found a faint comet while observing from Nantucket on 1 October 1847. The discovery brought international recognition to a skilled observer whose subsequent teaching helped expand women’s participation in professional astronomy.

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An early nineteenth-century scholar presents paper copies of Egyptian inscriptions to colleagues in a Paris meeting room.Science & discoveries

Champollion presents his hieroglyphic decipherment in 1822

Jean-François Champollion presented his Lettre à Monsieur Dacier on 27 September 1822. It marked a crucial public stage in understanding the relationship between Egyptian signs, sounds and language.

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A potted tropical seedling and hand tools stand before a small garden nursery and forested hills.Science & discoveries

Rio de Janeiro Botanical Garden's foundation and acclimatisation mission

Founded on 13 June 1808, Rio de Janeiro's Botanical Garden began with a practical mission: adapting valuable imported plants to Brazilian conditions. Its early experiments connected botany, trade and colonial economic ambitions.

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Workers uncover a large circular carved basalt monument during improvements to colonial Mexico City’s main square.Science & discoveries

Rediscovery of the Mexica Sun Stone in Mexico City

Found on December 17, 1790, the Sun Stone became a major subject of Mexican archaeological study. Its calendar signs belong to a wider vision of creation, solar movement and successive cosmic ages.

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An eighteenth-century observer uses a wooden reflecting telescope in a lantern-lit garden in Bath.Science & discoveries

William Herschel’s observation of Uranus on 13 March 1781

On 13 March 1781, William Herschel noticed an object that looked different from nearby stars. Its eventual identification as Uranus extended the known planetary system beyond Saturn and showed how observation and interpretation can unfold at different times.

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A seventeenth-century Dutch observer holds a small brass microscope close to his eye beside a vial of pepper-infused water.Science & discoveries

Leeuwenhoek’s 1676 letter on microscopic life in water

On 9 October 1676, Antoni van Leeuwenhoek dated a detailed letter describing living organisms in water and spice infusions, bringing an unseen world into scientific correspondence.

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Galileo looks through a long, narrow telescope beside an open window above Padua's rooftops.Science & discoveries

Galileo's first observations of lights beside Jupiter

On 7 January 1610, Galileo recorded three small lights near Jupiter and initially interpreted them as stars. Repeated observations revealed a system of orbiting moons, challenging the assumption that every celestial body revolved around Earth.

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A spectacle maker examines two lenses at a workbench beside an early spyglass and plain spectacles.Science & discoveries

Hans Lippershey applies to patent an early telescope

On 2 October 1608, Hans Lippershey sought a Dutch patent for an instrument that made distant objects appear nearby. The application anchors the early history of the telescope in a document, while leaving broader questions of invention open.

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