TIME: 65 million years ago.
PLACE: What is now the Yucatan Peninsula in eastern Mexico.
EVENT: The crash of an asteroid 20 kilometers across.
EFFECT: The end of the dinosaurs and most other life forms on Earth at the time.

Suppose you were a lumbering triceratops. What would your walnut-sized brain have registered when this fiery crash occurred? Answer: Basically, almost nothing beyond an unbelievably intense light in the sky before you were instantaneously reduced to a heap of ashes, or even obliterated entirely if you happened to be in the impact zone. Here’s the scenario.