Portal:History of science/Selected anniversaries/April 1
- 1640 - Birth of Georg Mohr, Danish mathematician (d. 1697)
- 1776 - Birth of Sophie Germain, French mathematician (d. 1831)
- 1826 - Samuel Morey patents the internal combustion engine
- 1865 - Birth of Richard Adolf Zsigmondy, Austrian-born chemist, Nobel Prize laureate (d. 1929)
- 1933 - Birth of Claude Cohen-Tannoudji, French physicist, Nobel laureate
- 1947 - Birth of Alain Connes, French mathematician
- 1968 - Death of Lev Davidovich Landau, Russian physicist, Nobel Prize laureate (b. 1908)
- 1976 - Jovian-Plutonian gravitational effect is first reported by the astronomer Patrick Moore
- 1981 - Daylight saving time is introduced in the USSR