METEOR CRATER

The Meteor Crater in the state of Arizona was the first crater to be identified as an impact crater. Between 20,000 to 50,000 years ago, a small asteroid about 80 feet in diameter impacted the Earth and formed the crater. Meteor Crater Arizona, USA The crater is the best preserved crater on Earth and measures 1.2 km in diameter. For many years, scientists had denied that there were any impact craters on Earth. The origin of this crater has been a source of controversy for many years. The discovery of fragments of the Canyon Diablo meteorite help prove that the feature was in fact an impact crater.

Meteor Crater Arizona, USA From the Smithsonian Scientific Series (1929), taken by the U.S. Army Air Service. Public domain.

Meteor Crater Arizona, USA From the Smithsonian Scientific Series (1938), public domain.

Meteor Crater Arizona, USA From the "World's Greatest Wonders" (1930), public domain.

Meteor Crater Arizona, USA Photos taken by Jim Hurley in the winter of 1978.

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