Portal:History of science/Selected anniversaries/January 3
- 1496 - Leonardo da Vinci unsuccessfully tests a flying machine
- 1641 - Death of Jeremiah Horrocks, English astronomer (b. 1618)
- 1722 - Birth of Fredric Hasselquist, Swedish naturalist (d. 1752)
- 1810 - Birth of Antoine Thomson d'Abbadie, French geographer (d. 1897)
- 1819 - Birth of Charles Piazzi Smyth, Astronomer Royal for Scotland (d. 1900)
- 1888 - The refracting telescope at the Lick Observatory, measuring 91 cm in diameter, is used for the first time. It was the largest telescope in the world at the time
- 1927 - Death of Carle David Tolmé Runge, German physicist (b. 1856)
- 1957 - The Hamilton Watch Company introduces the first electric watch
- 1969 - Death of Jean Focas, Greco-French astronomer (b. 1909)
- 1989 - Death of Sergei Lvovich Sobolev, Russian mathematician (b. 1909)