Arizona became the 48th state to join the United States of America.
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Alexander Graham Bell applied for a patent for the telephone.
Pale Blue Dot, an iconic photo of our Earth, was taken by Voyager 1 space probe.
Hundreds of Jews in Strasbourg, France, were publicly burnt to death.
The Saint Valentine's Day Massacre took place in Chicago.
The discovery of Earth's wobbling motion on its axis was presented to the Royal Society, London, in a letter written by astronomer James Bradley.