World War II altered the landscape of social and political structures across the globe. A denazification program in Germany led to the prosecution of Nazi war criminals in the Nuremberg trials as well as the removal of all former Nazis from power.
Atomic Bombings of Hiroshima and Nagasaki (1945)
On August 6 and August 9, 1945, the United States detonated two atomic bombs over the Japanese cities of Hiroshima and Nagasaki. The detonations killed between 129,000 and 226,000 individuals, almost all of whom were civilians. Weapons were never used in armed conflict again.
Both bombings had catastrophic effects on the cities. It took Japan two years to recover from the devastating incident. Otto Hahn, a German atomic scientist known as the father of nuclear chemistry, is reported as having said to his colleagues, "Once I wanted to suggest that all uranium should be sunk to the bottom of the ocean."
Sputnik (1957)
Sputnik 1 was the first-ever artificial earth satellite. The beach ball-sized device was launched into orbit by the Soviet Union on October 4, 1957. Three weeks later, its batteries died. After two months in space, Sputnik fell back into the atmosphere.