What is in a volcano?

A volcano is an opening on the surface of a planet or moon that allows material warmer than its surroundings to escape from its interior. When this material escapes, it causes an eruption. An eruption can be explosive, sending material high into the sky. read more

Volcano definition is - a vent in the crust of the earth or another planet or a moon from which usually molten or hot rock and steam issue; also : a hill or mountain composed wholly or in part of the ejected material. read more

A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface. Earth's volcanoes occur because its crust is broken into 17 major, rigid tectonic plates that float on a hotter, softer layer in its mantle. read more