The impact theory is one of the newest ideas in the catastrophic camp of dinosaur extinction. This theory states that a large object (or objects), such as an asteroid or comet, collided with Earth, resulting in a large impact crater, giant waves in the oceans that smashed onto land at heights of two to three miles (3.2 to 4.8 kilometers), and radical, rapid changes in Earth’s weather, temperature, amount of sunshine, and climate.