Comet showers as a cause of mass extinctions

Piet Hut; Walter Alvarez; William P. Elder; Thor Hansen; Erle G. Kauffman; Gerta Keller; Eugene Merle Shoemaker; Paul R. Weissman

doi:10.1038/329118a0

USGS · 70227580

Comet showers as a cause of mass extinctions

Piet Hut·Walter Alvarez·William P. Elder·Thor Hansen·Erle G. Kauffman·Gerta Keller·Eugene Merle Shoemaker·Paul R. Weissman

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Abstract

If at least some mass extinctions are caused by impacts, why do they extend over intervals of one to three million years and have a partly stepwise character? The solution may be provided by multiple cometary impacts. Astronomical, geological and palaeontological evidence is consistent with a causal connection between comet showers, clusters of impact events and stepwise mass extinctions, but it is too early to tell how pervasive this relationship may be.

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Piet Hut, Walter Alvarez, William P. Elder, Thor Hansen, Erle G. Kauffman, Gerta Keller, Eugene Merle Shoemaker, Paul R. Weissman. 1987. Comet showers as a cause of mass extinctions. https://doi.org/10.1038/329118a0

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