Meteoroids weighing 10,000 tons or more are barely slowed down by Earth's atmosphere. They hit the ground at a large fraction of their initial speed. These objects create impact craters. The rocks they collide with undergo enormous pressure. Once the shock wave has passed, the pressure in the compressed ground is released and the material is thrown out of the impact site. Very large meteoroids can be completely destroyed when the shock wave passes through them. Due to the heat, part of the Earth's rock is vaporized and falls back to the ground in the form of vitreous rocks called impactites and tektites.

On average, an impact crater is twenty times larger than the meteoroid that produced it. There are two types of craters. Simple craters are shaped like a bowl. Complex craters are much larger, at least 4 kilometres in diameter, with a raised centre. There are more than 172 impact structures throughout the world, 29 of which are in Canada. The surfaces of celestial bodies that do not have an atmosphere, such as Mercury, the Moon, and other planets' satellites, have many more craters. The absence of erosion and volcanic activity on these celestial bodies makes the impact structures eternal. On Earth, meteor impacts may have influenced the evolution of life by causing several mass extinctions.