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Scientists Find Signs of Meteor Crash That Led to Extinctions in Era Before Dinosaurs
by Kenneth Chang
February 23, 2001
Scientists examining the layer of sediment corresponding to the die-offs discovered concentrations of the sturdy, soccer-ball-shaped carbon molecules, buckminsterfullerenes, or buckyballs. Within the buckyballs was a mix of helium and argon gases similar to that found in certain stars but unlike anything that could form naturally on Earth. A few inches below and above the extinction layer, they found very few buckyballs... Recent work indicates the extinctions happened quickly, within 100,000 years. That led to speculation that an asteroid or comet impact might be to blame... The buckyballs and gases were found in samples from Japan and China, while a sample from Hungary was almost devoid of buckyballs. Other scientists said that samples from other regions would be needed to confirm the findings and to rule out other potential sources, like cosmic dust... Dr. Robert J. Poreda, a professor of earth and environmental sciences at the University of Rochester and another author on the Science paper, said the energy released by the meteor, estimated at four to eight miles wide, would have been equivalent to a magnitude-12 earthquake... Dr. Becker, Dr. Poreda and their colleagues had previously found buckyballs at an impact crater in Sudbury, Canada, and in two meteorites. They have also found buckyballs containing similar types of gases in sediments dating from the dinosaur extinctions.