Israeli Knesset chose April 13 as the official Holocaust Remembrance Day.
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Cardinal Bellarmine condemned Galileo for stating that the earth revolved around the sun.
Jonas Salk's Polio vaccine tested by Jonas Salk was given final approval by the US Food and Drug Administration.
Crusaders from the Fourth Crusade broke through Constantinople's walls and entered the great city.
The world's first person visited space.
Rock Around The Clock by Bill Haley and His Comets was recorded.
