1946: The United States detonated an atomic bomb at Bikini Atoll in the Pacific in the first underwater test of the device.
1952: Puerto Rico became a self-governing commonwealth of the United States.
1956: Fifty-one people died when the Italian liner Andrea Doria sank after colliding with the Swedish ship Stockholm off the New England coast.
1963: The United States, the Soviet Union and Britain initialed a treaty in Moscow prohibiting the testing of nuclear weapons in the atmosphere, in space and underwater.
1978: Louise Joy Brown, the first test-tube baby, was born in Oldham, England; she had been conceived through in-vitro fertilization.
1994: Israeli Prime Minister Yitzhak Rabin and Jordan’s King Hussein signed a declaration at the White House ending their countries’ 46-year-old formal state of war.