The dinosaurs’ fate may have been sealed by a piece of shrapnel from a cosmic collision that occurred long before the asteroid smashed into the Yucatán Peninsula 65 million years ago. Poring through a database of objects in the asteroid belt between Mars and Jupiter, scientists at the Southwest Research Institute in Boulder, Colorado, found debris from an ancient collision. In a chaotic cluster of asteroid shards, scientists glimpsed a void—evidence that part of the cluster had moved toward the inner planets, possibly sending the killer asteroid to Earth.
Asteroids are a lot like pinballs in the machine that is the solar system, says William Bottke of the SwRI team. “You shoot a ball and it goes all over the place, but if you shot a million balls and tracked where they went to the bottom, eventually you’d come up with trends.
Bottke and his colleagues were able to find patterns in the floating rocks and pinpoint the speed, distance, and direction the asteroids traveled after the initial collision. The researchers think the collision took place about 160 million years ago, with the major impactor reaching Earth some 95 million years later, about the time the dinosaurs went extinct.
