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The presence of Brenham meteorites in burial mounds as far away as Ohio—including jewelry fashioned out of Brenham meteorites—indicates that Native Americans, like modern collectors, were transfixed by these stunning extraterrestrial stones. While there is uncertainty regarding whether area Native Americans witnessed the fall itself, petroglyphs have been found nearby depicting what could have been the Brenham event. The appearance of this example is to be contrasted with lot 23, an oriented iron meteorite which exhibits the more typical presentation of regmaglypts. The ablative heat shield-like action pushed the hottest gasses created, referred to as the shock layer, hotter than the surface temperature of the sun, away from the meteorite. A significant fraction of the mass of this meteorite vaporized or ablated off its edges during its descent. The smoothness is the result of a repeating cycle in Earth’s upper atmosphere in which the more easily melted olivine crystals exposed tendrils of the nickel-iron matrix, which in turn melted and exposed more crystals, etc., until the meteorite slowed to terminal velocity. NASA engineers studied this angle in other oriented meteorites when designing the heat shields for the first manned space capsules.Īmong its other attributes, the Brenham main mass is also the largest oriented meteorite with a smoothed curvature. The parabolic "heat shield" curvature seen here was sculpted by some of the hottest temperatures found in nature, and is the most efficient angle at which heat deflects from a falling object. This is the largest pallasite found in North America and is also the largest intact pallasite in the world, yet it is the orientation of this specimen for which it is most renowned.Īs evidenced by its shape, this meteorite—unlike most—did not tumble or change its vertical axis as it plunged through Earth’s atmosphere. This is a pallasitic meteorite (see lots 46 and 48)—a group representing less than 1% of all meteorites.

The pedigree of this meteorite is highly distinguished it is the largest oriented meteorite with naturally-occurring gemstones—olivine and peridot—known to exist. Ebel, Curator of Meteorites at the American Museum of Natural History, stated that the value of this meteorite is in excess of one million dollars. Discovered outside of Greensburg, Kansas in 2005, scientists have referred to this offering as the most significant American meteorite discovery in decades. This is a matchless example of an oriented meteorite.