This account was first published 12 months ago, but I must have missed it. A very interesting read detailing events more clearly.

>>New simulations show that particles thrown into the atmosphere would have blocked sunlight for up to 18 months, disrupting the photosynthesis of plants and cascading into one of the worst mass extinction events the world has ever seen.

An impact by a massive asteroid, at least 10 km (6.2 miles) wide, is the leading theory on what caused the Cretaceous-Paleogene (K-Pg) extinction event, thanks to abnormal layers in the geologic record and the huge Chicxulub crater in the Gulf of Mexico, which dates back to the same time. While the dinosaurs are the most famous victims, scientists estimate that it also wiped out 93 percent of mammals alive at the time, and devastated most other species.<<

https://newatlas.com/dinosaur-asteroid-extinction-darkness/50995/