What Happened to the Dinosaurs? | CBC Kids

66 million years ago, dinosaurs ruled the Earth. And then, they suddenly became extinct. So what happened? Well, no one knows for sure. We're going to look at the most popular theory as we try to answer the question, what happened to the dinosaurs? Now, a long time ago, our planet was a different place. It was hotter. Plants and animals were bigger. And, well, there were dinosaurs everywhere. But to really understand what happened on Earth, we first need to look to outer space. Scientists believe a single massive asteroid struck our planet 66 million years ago. Think of an asteroid as a giant rock floating through space. But this particular asteroid was about 10 kilometers wide. It was colossal. And it was on a collision course with Earth. As it gathered incredible speed, it entered Earth's atmosphere like a fireball, tearing across the sky, and finally crashing into the Gulf of Mexico. The impact was so powerful that it kicked up rocks the size of buildings and sent huge clouds of dust into the sky. Then came a chain reaction of disasters, including forest fires, earthquakes, and 90-meter waves. It's believed that most of the life on Earth died off shortly after the asteroid struck. In the days and months after, the sun's warmth was blocked by dust and thick fog, and the Earth became very cold. This caused plants to die. And without plants, plant-eaters began to die. And without plant-eating animals to eat, the meat-eaters died off, too. After ruling Earth for 165 million years, the age of the dinosaur came to a sudden end. Of course, the story of life on our planet doesn't end there. As years passed, the Earth healed. The air cleared. Trees and plants returned, paving the way for new species like mammals to one day become the dominant beings on Earth.