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It's just 30 minutes east of Flagstaff, off Exit 233 and at the end of a 6-mile, yet seemingly interminable road extending south into the center of nothing. It sits isolated in the middle of a deserted tableland, a pockmark nearly a mile wide interrupting an otherwise unmitigated horizontality, as if God himself took a melon baller to the Colorado Plateau. At the rim, which rises 150 feet from the surrounding flatland, one can look down from a suspended platform to witness what the absence of roughly 80 million cubic yards of dirt looks like. It's nearly a mile to the other side and well over 500 feet to the bottom. Though wind erosion has filled it in just a little in the last few millennia, it appears today very much like it did shortly after its formation 50,000 years ago, making it the most well-preserved impact crater on Earth. The forces in creating the giant pothole were so great, they can be difficult to wrap your brain around. Some 175 million tons of rock were displaced when the meteor responsible hit the planet, scattering debris for over a mile. Limestone boulders the size of houses were blown onto the rim. The compression forces at the moment of impact were so intense––more than 20 million pounds per square inch––that small amounts of graphite present in the meteor were instantly turned to microscopic diamonds. Most of the material melted or vaporized. |
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If you're still having trouble grasping those figures, don't worry. The world's leading scientists only recently worked it out, themselves. Until the 1960s, when famed scientist Eugene Shoemaker published his findings, not everyone was convinced the crater was even caused by a meteor. At first, it was dismissed as the result of a steam explosion. In 1891, the chief geologist for the U.S. Geological Survey, G.K. Gilbert, figured any supposed meteorite would be almost as big as the crater itself and would be buried beneath the surface. But since the theoretical mass of iron didn't affect his compass, it couldn't be there. So, the cause had to be volcanic. All the meteorites found nearby were just coincidence. A decade later, a mining engineer named Daniel Barringer disagreed. Learning that meteorites were mixed with the ejected material, he was positive it had to be an impact crater. Still, like Gilbert, he remained convinced the meteorite was underground. Calculating its composition at 10 million tons of iron, he knew he could make a fortune mining it. Over the next 27 years, he spent the equivalent of $10 million hunting the object, drilling more than two dozen shafts in his search. Finding nothing, Barringer was forced to call it quits in 1929. He died of a heart attack just weeks later. Yet, Barringer's efforts weren't wasted, at least not scientifically speaking. Even though he was wrong about the meteorite, the evidence he uncovered in all his years of research and exploration continued to support his impact hypothesis. Though he encountered relentless opposition from those who disagreed, the scientific community eventually accepted his theory and Meteor Crater became the first proven impact feature on Earth. |