Top 12 Biggest Impact Craters on Earth

An impact crater is the result of a collision between an astronomical object and Earth. Our planet has been impacted a surpringly large number of times, luckily most often in the extremely distant past. Some craters are not visible at the surface due to erosion or environmental changes and some are deep in the sea. In total, we know of 190 sites around the world that have been hit by asteroids, comets or meteorites. Some of these impacts were so enormous that they created conditions that led to extinction events. This graphic maps the top 12 largest impact craters by diameter, along with a timeline of when they occurred.