One of the best-preserved and the most famous terrestrial meteorite impact crater, 55 km east of Flagstaff, Arizona; also known as Barringer Crater. The crater is 1.2 km in diameter, 175 m deep, and its rim rises an average of 45 m above the surrounding plains. It was formed about 50 000 years ago when a nickel–iron meteorite, about 50 m across and weighing several hundred thousand tonnes, hit the desert at about 16 km/s. The energy of the impact, equivalent to about 20 megatonnes of TNT, excavated over 175 million tonnes of limestone and sandstone to produce the crater. The meteorite vaporized or melted almost completely on impact, any remaining material being scattered around the crater. Over 10 000 nickel–iron octahedrite meteorite fragments have been recovered, up to 7 km from the crater. The crater's impact origin was recognized in the 1930s, mainly through the efforts of the American mining engineer Daniel Moreau Barringer (1860–1929).
http://www.meteorcrater.com/ Meteor Crater Visitor Center and information website.
Subjects: Astronomy and Astrophysics.