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Meteor Crater, or Barringer Crater, is an impact crater about east of Flagstaff and west of Winslow in the desert of northern Arizona, United States. The site had several earlier names, and fragments of the meteorite are officially called the Canyon Diablo Meteorite, after the adjacent Canyon Diablo.La Pas, L. (1943). "Remarks on four notes recently published by C. C. Wylie", Popular Astronomy, vol. 51, p. 341
Meteor Crater lies at an elevation of above sea level.Images of America: Meteor Crater (p. 107), Neal F. Davis, Arcadia Publishing, 2016. . It is about in diameter, some deep, and is surrounded by a rim that rises above the surrounding plains. The center of the crater is filled with of rubble lying above crater bedrock. One of the features of the crater is its squared-off outline, believed to be caused by existing regional jointing (cracks) in the strata at the impact site.
Despite an attempt to make the crater a public landmark, the crater remains privately owned by the Barringer family to the present day through their Barringer Crater Company. The Lunar and Planetary Institute, the American Museum of Natural History, and other science institutes proclaim it to be the "best-preserved meteorite crater on Earth". It was designated a National Natural Landmark in November 1967.
The object that excavated the crater was a nickel-iron meteorite about across. The speed of the impact has been a subject of some debate. Modeling initially suggested that the meteorite struck at up to , but more recent research suggests the impact was substantially slower, at . About half of the impactor's bulk is believed to have been vaporized during its descent through the atmosphere. Impact energy has been estimated at 10 TNT equivalent. The meteorite was mostly vaporized upon impact, leaving few remains in the crater.Schaber, Gerald G. "The U.S. Geological Survey, Branch of Astrogeology – A Chronology of Activities from Conception through the End of Project Apollo (1960–1973)", 2005, U.S. Geological Survey Open-File Report 2005-1190. (PDF)
Since the crater's formation, the rim is thought to have lost of height at the rim crest as a result of natural erosion. Similarly, the basin of the crater is thought to have roughly of additional postimpact sedimentation from lake sediments and alluvium. Very few remaining craters are visible on Earth, since many have been erased by erosive geological processes. The relatively young age of Meteor Crater, paired with the dry Arizona climate, has allowed this crater to remain comparatively unchanged since its formation. The lack of erosion that preserved the crater's shape greatly accelerated its groundbreaking recognition as an impact crater from a natural celestial body.
Barringer had amassed a small fortune as an investor in the successful Commonwealth Mine in Pearce, Cochise County, Arizona. Barringer believed that the bulk of the Meteor Crater impactor could still be found under the crater floor. Impact physics was poorly understood at the time, and Barringer was unaware that most of the meteorite had vaporized on impact. Barringer incorporated a company, the Standard Iron Company, and staked a mining claim on the land, hoping to mine the asteroid that had produced the crater.Southgate, Nancy; Barringer, Felicity (2002). A Grand Obsession: Daniel Moreau and His Crater. Barringer Crater Co. He estimated from the size of the crater that the meteorite had a mass of 10 million tons.
The metal content of the iron meteorites found around the crater was valued at the time at US$125/ton, so Barringer was searching for a lode he believed to be worth more than a billion 1903 dollars. "By 1928, Barringer had sunk the majority of his fortune into the crater – $500,000, or roughly $ million in dollars."
Barringer spent 27 years trying to locate the nonexistent deposit of meteoric iron, and drilled to a depth of , but no significant deposit was ever found.
Barringer was politically well-connected. He received a land patent signed by Theodore Roosevelt for 640 acres (1 sq mi, 260 ha) around the center of the crater in 1903. (2025). 9781862391949, Geological Society. ISBN 9781862391949 In 1906, at his request, President Roosevelt also authorized the establishment of a post office unconventionally named "Meteor", located at Sunshine, a stop on the Atchison, Topeka and Santa Fe Railway, north of the crater. The Meteor post office closed on April 15, 1912, due to disuse.
In 1929, astronomer F. R. Moulton was employed by the Barringer Crater Company to investigate the physics of the impact event. Moulton concluded that the impactor likely weighed as little as 300,000 tonnes, and that the impact of such a body would have generated enough heat to vaporize the impactor instantly. Barringer died just ten days after the publication of Moulton's second report.
By this time, "the great weight of scientific opinion had swung around to the accuracy of the impact hypothesis ... Apparently an idea, too radical and new for acceptance in 1905, no matter how logical, had gradually grown respectable during the intervening 20 years."
Nininger believed that the crater should be a national monument and, in 1948, he successfully petitioned the American Astronomical Society to pass a motion in support of nationalizing the crater by making "the unauthorized—and false—claim that the Barringers would be receptive to a fair purchase for the crater." By this time, mining activity at the crater had ceased, and the Barringers were in the process of planning a tourist attraction on the rim of the crater. Nininger was operating the American Meteorite Museum nearby, on Route 66, at the time. Nininger hoped that a public museum could be built on the crater's rim, and that the project might lead to the founding of a federal institute of meteorite research. Offended by Nininger's attempt to nationalize the crater, the Barringer family promptly terminated his exploration rights and ability to conduct further fieldwork at the crater. A few years later, in 1953, the Standard Iron Company was renamed the "Barringer Crater Company," and a private museum was constructed on the crater rim.
Geologists used the nuclear detonation that created the Sedan crater, and other such craters from the era of atmospheric nuclear testing, to establish upper and lower limits on the kinetic energy of the meteor impactor.
Soils around the crater are brown, slightly to moderately alkaline, gravelly or stony loam of the Winona series; on the crater rim and in the crater itself, the Winona is mapped in a complex association with rock outcrop.
On August 8, 1964, two commercial pilots in a Cessna 150 flew low over the crater. After crossing the rim, they could not maintain level flight. The pilot attempted to circle in the crater to climb over the rim. During the attempted climb out, the aircraft stalled, crashed, and caught fire. The plane is commonly reported to have run out of fuel, but this is incorrect. Both occupants were severely injured, but survived. A small portion of the wreckage not removed from the crash site remains visible. Plane Crash At Meteor Crater Revisited, September 1, 2008 Meteorite-times.com
In 2006, a project called METCRAX (for METeor CRAter eXperiment) investigated "the diurnal buildup and breakdown of basin temperature inversions or and the associated physical and dynamical processes accounting for their evolving structure and morphology."
Eugene M. Shoemaker
Eugene Merle Shoemaker continued investigations at the crater. A key discovery was the presence in the crater of the minerals coesite and stishovite, rare forms of silica found only where quartz-bearing rocks have been severely shocked quartz by an instantaneous overpressure. Shocked quartz cannot be created by volcanic action; the only known mechanisms of creating it are naturally through lightning or an impact event, or artificially, through a nuclear explosion.Shoemaker, Eugene M. (1987). "Meteor Crater, Arizona", Geological Society of America Centennial Field Guide – Rocky Mountain Section. In 1960, Edward C. T. Chao and Shoemaker identified coesite at Meteor Crater, adding to the growing body of evidence that the crater was formed from an impact generating extremely high temperatures and pressures. He confirmed what F.R. Moulton and H.H. Nininger already proposed: the impact vaporized the vast majority of the impactor. The pieces of Canyon Diablo meteorite found scattered around the site broke away from the main body before and during the impact. Shoemaker published his conclusions in his 1974 book, the Guidebook to the geology of Meteor Crater, Arizona.
Geology
The impact created an inverted stratigraphy, so that the layers immediately exterior to the rim are stacked in the reverse order to which they normally occur; the impact overturned and inverted the layers to a distance of 1–2 km outward from the crater's edge. Specifically, climbing the rim of the crater from outside, one finds:
Climate
Recent history
During the 1960s and 1970s, NASA trained in the crater to prepare for the to the Moon, and ongoing field training for astronauts continues to this day.
Tourist attraction
Meteor Crater is a popular tourist destination with roughly 270,000 visitors per year. The crater is owned by a family company, the Barringer Crater Company. Meteor Crater is an important educational and research site.D. A. Kring, 2017, Guidebook to the Geology of Barringer Meteorite Crater, Arizona (aka Meteor Crater), Second edition, Lunar and Planetary Institute (Contribution No. 2040), Houston, 272p.
/ref>N. F. Davis, 2016, Images of America: Meteor Crater, Arcadia Publishing, Charleston, 127p. The Meteor Crater Visitor Center sits on the north rim of the crater. It features interactive exhibits and displays about meteorites and asteroids, space, the Solar System, and comets including the American Astronaut Wall of Fame and such artifacts on display as an Apollo boilerplate command module (BP-29), a meteorite found in the area, and meteorite specimens from Meteor Crater that can be touched. Formerly known as the Museum of Astrogeology, the Visitor Center includes a Discovery Center & Space Museum,"Meteor Crater". Meteor Crater. Retrieved 2022-6-24.
a movie theater, a gift shop, and observation areas with views inside the rim of the crater. Guided tours of the rim are offered daily, weather permitting.
See also
External links
Categories: Impact Craters Of The United States, National Natural Landmarks In Arizona, Pleistocene Impact Craters, Tourist Attractions Along U.s. Route 66, Museums In Coconino County, Arizona, Science Museums In Arizona, Geology Museums In Arizona, Landforms Of Coconino County, Arizona, Tourist Attractions In Coconino County, Arizona, Space-related Tourist Attractions
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