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 ...

The Earth is made up of different layers: Therefore, instead of tectonic plates moving because of the convection currents, evidence suggests it is the plates that drive the convection. Slab pull ...

Researchers had long suspected the Earth had another layer at its core, but because its composition is so similar to the layer surrounding it, the innermost inner core was hard to spot.