History
The asteroid fell about 50,000 years ago. The meteorites have been known and collected since the mid-19th century and were known and used by pre-historic Native Americans. The Barringer Crater, from the late 19th to the mid-20th century, was the center of a long dispute over the origin of craters that showed little evidence of volcanism. That debate was settled in the 1950s thanks to Eugene Shoemaker's study of the crater.
In 1953, Clair Cameron Patterson measured ratios of the lead isotopes in samples of the meteorite. The result permitted a refinement of the estimate of the age of the Earth to 4.550 billion years (± 70 million years).
Read more about this topic: Canyon Diablo (meteorite)
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“The history of philosophy is to a great extent that of a certain clash of human temperaments.”
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“History, as an entirety, could only exist in the eyes of an observer outside it and outside the world. History only exists, in the final analysis, for God.”
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