1801: Predicted by the Titius–Bode law, the presence of a body between Mars and Jupiter is confirmed by Giuseppe Piazzi o
1117: A chronicler in the principality of Liège recorded the great earthquake of Verona.
1496: On this day, Leonardo da Vinci reportedly tested his 'ornithopter', a human-powered flying machine near Florence, Italy.
1643: Birthday of Isaac Newton (date converted to the Gregorian calendar).
1896: An Austrian newspaper reports that Wilhelm Röntgen discovered a type of radiation, later known as X-rays.
1610: Galileo Galilei observes Jupiter's four largest moons for the first time.
1642: Death of Galileo Galilei. This Italian astronomer, physicist and engineer became famous for his numerous observations and discoveries.
1828: Adolphe Quetelet is officially appointed director of the Observatory.
1882: Birth of Eugène Delporte. He discovered 66 asteroids and was director of the Observatory from 1936 to 1947.
1787: William Herschel discovers Titania and Oberon, two moons of Uranus.
1923: G. Van Biesbroeck discovers the asteroid 993 and names it "Moultona" after his American colleague Forest R.
1610: Galileo Galilei discovers Callisto, the fourth moon of Jupiter.
1938: The Anglican Church accepts the theory of evolution.
1742: Death of Edmond Halley, English scientist (born 1656), known for predicting the return of the comet named after him.
2005: The European lunar probe SMART-1 discovers elements such as calcium, aluminium, silicon, iron and other surface elements on the moon.
1966: An earthquake measuring 4.4 on the Richter scale occurs in Chapelle-lez-Herlaimont.
1706: Birth of Benjamin Franklin, American diplomat and co-author of the United States Declaration of Independence.
1916: A 611-gram meteorite (chondrite type) strikes a house in the village of Baxter in Stone County, Missouri.
1988: Henri Debehogne discovers asteroid 5727 and names it "Pierobenvenuti", in honour of Italian astronomer Piero Benvenuti (born 1946) for his lo
1988: Henri Debehogne discovers asteroid 3866 and names it "Langley", after Samuel Pierpont Langley (1834-1906), third secretary of the Smithsonian
1880: Birth of Georges Van Biesbroeck, discoverer of many asteroids at the Observatory.
1898: Death of Carl Wiencke. He fell overboard from the Belgica during a storm.
1960: During a record-breaking dive, the bathyscaphe USS Trieste becomes the first manned vessel to reach the bottom of Challenger Deep, in the Mar
1918: Introduction of the Gregorian calendar in Russia by decree of the Council of People's Commissars, effective from 14 February (new style).
2004: Landing of MER-B (also known as Opportunity or Oppy) in Meridiani Planum on Mars.
1933: Eugène Delporte discovers asteroid 2545 and names it "Verbiest", after the Flemish missionary and imperial astronomer in China, Father Ferdin
1993: Erik Elst discovers three asteroids on the same day: nr. 11302 "Rubicon", named after the famous river in Roman history; nr.
1611: Birthday of Johannes Hevelius, German-Polish astronomer.
1905: Death of François Folie, director of the Observatory during the construction of the Uccle site (intended to replace th
1992: Erik Elst discovers 11 new asteroids, of which he named No10101 after French mathematician Jean-Baptiste Fourier, and No13975 after English w
2012: At La Silla, the new TRAPPIST telescope discovers asteroid 541897, named 'Trappist'.
1890: Death of Charles Fiévez, scientist who performed research in spectroscopie and had already discovered the Zeeman effect, but was unable to pu
1893: Death of François Van Rysselberghe, meteorologist at the Royal Observatory (later RMI).
1906: Birth of Clyde Tombaugh, American astronomer (died 1997), discoverer of Pluto.
1959: Jack Kilby of Texas Instruments files the first patent for an integrated circuit.
1889: Birth of Harry Nyquist, important theorist in the field of information theory (died 1976).
Birth of Dmitry Ivanovich Mendeleev, a Russian chemist who developed the periodic classification of the elements.
1986: Comet Halley reaches perihelion during its second visit to the inner solar system in the 20th century.
1923: Death of Wilhelm Röntgen, German physicist and Nobel laureate (born 1845).