About 66 million years ago, a 10-km- (6.2-mile) wide asteroid crashed into Earth near the site of the small town of Chicxulub in what is now Mexico. While this impact is firmly linked to the end-Cretaceous extinction of non-avian dinosaurs and 75% of life on the planet, the temporal relationship of the lesser-known Boltysh impact structure in Ukraine to these events is uncertain, although it is thought to have occurred 2,000 to 5,000 years before...
