To learn why, where, and how earthquakes happen, you need to familiarize your students with the interior of the Earth and a model called plate tectonics. The engine behind the earthquake machine ...

The Earth's interior is composed of four layers, three solid and one liquid—not magma but molten metal, nearly as hot as the surface of the sun. The deepest layer is a solid iron ball ...

Perhaps more inaccessible than the nearest star, it is revealed by earthquakes. These indicate that matter in the earth's inner core is so highly compressed that it is twice as rigid as steel ...

Many geologists attribute the great variation in the temperature gradient to complex irregularities in the structure of the earth's crust. Some even maintain that the interior of the earth is cold ...

The InSight probe aims to study the world's deep interior, and make it the only planet - apart from Earth - that has been examined in this way. Confirmation of touchdown came through on cue at 19: ...