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No. 45: May-Jun 1986

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Disparity Between Asteroids And Meteorites

Since the meteorites we pick up on earth (Antarctica and elsewhere) are thought to have come from pulverized asteroids, it is something of a shock to find profound dissimilarities between asteroids and meteorites.

"The problem is that while reflectance spectra of some meteorites measured in the laboratory appear to correspond to spectra of various asteroids, the S class, which makes up about half of all asteroids in the inner belt, doesn't appear to match any common meteorite class, and conversely, common meteorite classes (e.g., Ordinary Chondrites) appear to match only a few asteroids."

(Harris, Alan W.; "Asteroid 29 Amphitrite Is a Topic of Interest," Geotimes, 30:25, June 1985.)

Comment. Note that the visual meteors or shooting stars that burn up high in the atmosphere are believed to be cometary debris (SF#44) and mostly ice and dust. The meteors large and substantial enough to make it through the atmosphere and arrive at the surface as meteorites must have a different source -- something more palpable, such as the asteroids, but the spectral disparities reported above may force a reevaluation of this theory.

From Science Frontiers #45, MAY-JUN 1986. 1986-2000 William R. Corliss