The sky is falling

6 theories that explain why dinosaurs really went extinct

MARK GARLICK/SCIENCE PHOTO LIBRARY/Science Photo Library/Getty Images

Even if you weren’t paying attention in science class, you probably know that an asteroid (known to scientists at the Chicxulub impactor) killed the dinosaurs.

It’s a fact that even kids’ cartoons and bizarre ‘90s sitcoms assume everyone knows — so why is this 66-million-year-old case still open?