End of an Era
vast asteroid or comet, 7 miles (10 km) across, slams into the Earth at a speed measured in
kilometres per second. It was an event such as this which ended the reign of the dinosaurs and other
species some 65 million years ago, the so-called Cretaceous-Paleogene (K–Pg) extinction event. We
see the impact as it may have looked from above a layer of cumulus cloud.