An impact crater is a depression in the surface of a solid astronomical body formed by the hypervelocity impact of a smaller object. In contrast to volcanic craters, which result from explosion or internal collapse, impact craters typically have raised rims and floors that are lower in elevation than the surrounding terrain. Impact craters are typically circular, though they can be elliptical in shape or even irregular due to events such as landslides. Impact craters range in size from microscopic craters seen on lunar rocks returned by the Apollo Program to simple bowl-shaped depressions and vast, complex, multi-ringed impact basins. Meteor Crater is a well-known example of a small impact crater on Earth.
500-kilometre-wide (310 mi) crater Engelier on Saturn's moon Iapetus
Recently formed (between July 2010 and May 2012) impact crater on Mars showing a pristine ray system of ejecta
50,000-year-old Meteor Crater east of Flagstaff, Arizona, U.S. on Earth
Eugene Shoemaker, pioneer impact crater researcher, here at a crystallographic microscope used to examine meteorites
In geology, a depression is a landform sunken or depressed below the surrounding area. Depressions form by various mechanisms.
A watering hole is a natural depression where water collects and animals come to drink.
Karst closed depression with permanent lake Stymfalia, Peloponnese, Greece. Seasonal abundant precipitation drained by 3 sinkholes
