 By Ned Rozell September 09, 2006
Roland Gangloff never ran that classified ad, but he might have considered it. Gangloff, former earth science curator at the museum, once uncovered a mystery when researching the Aggie Creek meteorite, the largest heavenly body fragment ever found in Alaska. When miners discovered the iron-nickel meteorite clanging around in the rock tumbler of a gold dredge in 1942, it was reported to weigh about 95 pounds. Today it weighs 57 pounds. Its curious weight-loss program is what Gangloff calls "one of those great Alaska mysteries." The mystery of the Aggie Creek meteorite began long, long ago. No one knows exactly how it was formed, but here's a possible scenario: A planetary body large enough to have a solid core broke apart after a violent collision with something bigger. Fragments scattered, including iron-nickel chunks from the core. After a collision with other space-borne matter, a piece was sent hurling toward the Earth. Earth's gravitational pull drew the metal chunk closer. The meteor heated into a glowing mass as it whizzed through the atmosphere, and it was large enough that it didn't melt to nothing, as do most meteors that enter the atmosphere. It whistled like a World War I mortar as it sped toward the area where Aggie Creek now flows from Fish River, about 15 miles east of Council on the Seward Peninsula. With a heavy thud, the metal chunk became a meteorite when it struck the ground in the Aggie Creek watershed. Years later, in 1942, miners noticed a way-too-heavy rock banging through their gold dredge. Eskil Anderson, a mining geologist from Spokane, flew to Aggie Creek, brought the meteorite to Nome and then donated it to the University of Alaska Museum. The Aggie Creek meteorite is one of the rarer types of those two dozen or so meteors a year that survive the trip through the atmosphere to strike Earth. Most common, and most difficult to identify as otherworldly, are stone meteorites. A distant second goes to meteorites composed of stone mixed with iron. Solid metal meteorites, such as one found at Aggie Creek, are rare finds indeed. The Aggie Creek meteorite now sits within a vault in the belly of the museum. About the size of a football but as heavy as a truck battery, the meteorite looks like a rusted orange rock with thumb print indentations, caused by uneven melting during its downward plunge toward Earth. One end of the meteorite has been sliced off. Gangloff said three other institutions, in Washington, D.C., Chicago, and Arizona, have samples of the Aggie Creek meteorite. But he said those pieces, swapped for meteorites the University of Alaska Museum didn't have, would collectively weigh nowhere near the missing 40 pounds. "Somewhere along the line somebody sliced half of it off and gave the rest to the museum," Gangloff said after pondering the missing metal. Later, he speculated that perhaps several meteorites were collected and weighed together. Other possibilites are that the meteorite was weighed with a faulty scale or was inaccurately listed in the Catalogue of Meteorites. If it wasn't a typographical error, a chunk of the meteorite may now be languishing somewhere around Alaska, perhaps holding open a door in some long-abandoned mine office. There is incentive to find it. Gangloff said because the Aggie Creek meteorite is worth somewhere in the neighborhood of $40,000, a companion piece may be worth as much, or even more if the combination of pieces makes an even rarer piece of celestial metal. That's some doorstop.
This column is provided as a public service by the Geophysical Institute, University of Alaska Fairbanks, in cooperation with the UAF research community. Ned Rozell is a science writer at the institute. This article was previously published. Select articles will be reprinted while Ned Rozell is on paternity leave. Publish A Letter on SitNews Read Letters/Opinions
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