Timeline of Cretaceous–Paleogene extinction event research Hildebrand and William Boynton reported the Chicxulub crater in the Yucatan peninsula of Mexico as a probable impact site. While the controversy continued, the accumulating evidence gradually began to sway the scientific community toward the Alvarez hypothesis. In 2010, an international panel of researchers concluded that impact best explained the extinction event and that Chicxulub was indeed the resulting crater. Because the estimated date of the object's impact and the Cretaceous–Paleogene boundary (K–Pg boundary) coincide, there is now a scientific consensus that this impact was the Cretaceous–Paleogene extinction event which caused the death of most of the planet's non-avian dinosaurs
Manson crater Manson crater The Manson crater is an impact crater near the site of Manson, Iowa where an asteroid or comet nucleus struck the Earth during the Cretaceous Period, 74 Ma (million years ago). It was one of the largest known impact events to have happened in North America. Previously it was thought to have led to the extinction of the dinosaurs until isotopic ages proved that it was too old. No surface evidence exists due to comparatively recent coverage by glacial till, and the site where the crater lies buried is now a flat landscape. But, hidden about below the