An asteroid becomes a meteorite when it travels to Earth from a nearby orbit or the outer solar system and collides with Earth, according to the United States Geological Survey. Small asteroids typically burn up in the upper atmosphere before ever reaching Earth’s surface to become meteorites.

News broke last week that an asteroid could potentially collide with Earth in the next eight years. But what do you need to know about the space rock that astronomers say is capable of leveling a mid-sized city?