How did Barosaurus dinosaurs die?

Ankylosaurus died out 65.5 million years ago, at the same time as all non-avian dinosaurs, pterosaurs, plesiOSaurs, and mosasaurs went extinct. They died out during the K-T Extinction Event, which is believed to have been caused by a 6 mile wide asteroid that crashed into the Yucatan Peninsula, leaving a 100 mile wide crater. The dust and ash thrown into the atmosphere blocked sunlight for months or years, which killed plants, as well as the animals that ate them, including Ankylosaurus.