Researchers identify CO chondrite meteorite as likely dinosaur-killing impactor

A rare CO chondrite meteorite likely caused the dinosaur extinction 66 million years ago, wiping out 75% of species. New nickel isotope analysis of impact samples identified this specific, less common meteorite class. This finding refines understanding of the extinction event's cause. The rare meteorite's composition suggests atmospheric debris, not sulfur, was the primary extinction factor. Its origin remains uncertain.