Catastrophism is the theory that cataclysms occurred in the times of the ancients, which were the basis for ancient myths. Welcome to our workspace on catastrophism.
The most famous catastrophist was Immanuel Velikovsky. Here's the folder devoted to the study of his works, in the "QDL / Topics / Science / Astronomy / Documents" folder.
Other theorists have gone beyond Velikovsky. Here is a folder devoted to the study of their stuff.
Here are other topics being explored. (Note that while there have been other collisions, such as the one addressed by the Shock Dynamics
model, the Catastrophism Team is focused just on collisions that happened within human memory.)