Portal:History of science/Selected anniversaries/January 20
- 1775 - Birth of André-Marie Ampère, French physicist (d. 1836)
- 1812 - Birth of Thomas Meik, Scottish engineer (d. 1896)
- 1910 - Birth of Joy Adamson, Austrian naturalist and writer (d. 1980)
- 1931 - Birth of David Lee, American physicist, Nobel Prize in Physics laureate
- 1948 - Birth of Natan Sharansky, Russian-born physicist and politician
- 2005 - Death of Miriam Louisa Rothschild, British zoologist, entomologist, and author (b. 1908)