March 20

1916 - Albert Einstein publishes his general theory of relativity.
1948 - Actor John de Lancie (Q being) is born.
1964 - The precursor of the European Space Agency, ESRO (European Space Research Organization) is established per an agreement signed on June 14, 1962.
2015 - A Solar eclipse, equinox, and a supermoon all occur on the same day.