I thought we were hit by an iridium-rich meteor, and that that was settled science.
The British 'sciences' remain mired in gradualism and Darwinism, which will take some of the sting out of the eventual muzzie takeover there. Natural selection is, best case, a model for extinction -- but if most extinctions happen in large bunches, which is demonstrable, then there's no more need for a just-so story like natural selection. Their solution is Impact Denialism.
That was at the end of the Cretaceous period about 66 million years ago. This article is about an event 170 million years ago.
I think a series of asteroids hit along with the 6 mile one.
The earth rang from the hits which triggered the volcanoes which helped kill off what were left of the dinosaurs that did not get incinerated.