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Lot Essay
Traveling at a speed of 66,000 kilometers per hour, a giant fireball entered Earth's atmosphere over Kazakhstan on 15 February 2013. At an altitude of 45 kilometers, atmospheric friction resulted in the largest portion—a 12,000-ton, 19-meter rock—to start breaking up. As fragmentation increased so did the amount of atmospheric drag, and when the object could not withstand the pressure, it exploded in a massive air burst 30 kilometers over the Russian city of Chelyabinsk. The total kinetic energy released was equivalent to 500 kilotons of TNT (approximately 25 times more energy than released by the atomic bomb that destroyed Hiroshima). Fortunately, most of this energy was dispersed and absorbed by the surrounding atmosphere. Ninety seconds later the shockwave reached the ground: people were knocked off their feet, 7,200 buildings in six cities were damaged and 100,000 homeowners had to replace broken windows. Worse still, more than 1100 people were injured, most from shattered glass and some for ultraviolet burns and temporary flash blindness. The Chelyabinsk shockwave left a trail of damage nearly 200 kilometers wide—and it could have been far worse: had the meteoroid exploded at a lower altitude, its explosive force would have been more focused and concentrated and the result would have been horrific. Chelyabinsk is the only meteorite documented to have resulted in a large number of injuries. It's also the only meteorite whose final moments were extensively documented on video: hundreds of security cameras and dash-cams recorded Chelyabinsk's descent, as well as video of exploding windows and collapsing walls. While most of the Chelyabinsk mass disintegrated in the atmosphere, thousands of small meteorites landed on Earth—and this is among the finest.
Fully oriented meteorites like this example are rare; unlike 99% of meteorites, this sample maintained the same orientation as it descended through the atmosphere. The parabola in evidence is the curvature at which heat most efficiently deflects from a falling body. As such, this curve was emulated in the heat shield design of the Mercury, Gemini and Apollo space capsules. A low-pressure zone forms on its far side of an oriented meteorite as it plunges through the atmosphere, resulting in the boiling of pooled molten material. One would then expect the character of the far side of a perfectly oriented meteorite to be wildly different than the oriented face—and that is abundantly evident in the specimen now offered.
Fully oriented meteorites like this example are rare; unlike 99% of meteorites, this sample maintained the same orientation as it descended through the atmosphere. The parabola in evidence is the curvature at which heat most efficiently deflects from a falling body. As such, this curve was emulated in the heat shield design of the Mercury, Gemini and Apollo space capsules. A low-pressure zone forms on its far side of an oriented meteorite as it plunges through the atmosphere, resulting in the boiling of pooled molten material. One would then expect the character of the far side of a perfectly oriented meteorite to be wildly different than the oriented face—and that is abundantly evident in the specimen now offered.