A crater is a bowl-shaped geological feature. In astronomy, the term ‘crater’ usually refers to an impact crater or a volcanic crater.

Impact craters are depressions found on astronomical bodies that result from high-velocity impacts with smaller bodies. An example would be the Barringer crater in Arizona which was caused by a meteorite impact about 50,000 years ago.

Volcanic craters usually crown conical volcanoes and form the opening of the volcanic vent, where lava pools when magma is rising to the surface. The craters of extinct and dormant volcanoes contain solidified lava (igneous rock) and sometimes fill with rain water, such as Crater Lake in Oregon, USA.

The Barringer meteor crater in Arizona, USA.
Credit: D. Roddy (LPI)