UCSB scientists have discovered evidence that suggests a large celestial rock – which could have been more than three miles across – may have exploded over North America 13,000 years ago. The discovery, made by paleoceanographer James Kennett and research scientist Luann Becker, could solve long-lingering questions about the continent. The blast could have killed off vegetation that was the food supply of many larger mammals, like the woolly mammoths.
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