Portal:History of science/Selected anniversaries/September 9
- 1737 - Birth of Luigi Galvani, Italian physician and physicist (d. 1798)
- 1839 - John Herschel takes the first glass plate photograph
- 1841 - Death of A. P. de Candolle, Swiss botanist (b. 1778)
- 1922 - Birth of Hans Georg Dehmelt, German-born physicist, Nobel Prize laureate
- 1947 - First actual case of a computer bug being found: a moth lodges in a relay of a Harvard Mark II computer at Harvard University
- 1985 - Death of Paul Flory, American chemist, Nobel Prize laureate (b. 1910)
- 2003 - Death of Edward Teller, Hungarian-born physicist (b. 1908)