In 1945 – The United States detonated a plutonium-based test nuclear weapon at the Alamogordo Bombing and Gunnery Range in New Mexico. The Trinity test ushered in the atomic age.
In 1951 – VisiCalc creator Dan Bricklin was born in Philadelphia.
In 1969 – Neil A. Armstrong, Edwin E. Aldrin, Jr., and Michael Collins, blasted off from Cape Kennedy on Apollo 11, the first manned mission to the surface of the moon.