Earth's interior is made up of a series of layers that sit below the surface crust. In order of depth, these layers include the solid, but flowing mantle, the liquid outer core and the solid iron outer core, which helps create Earth's protective magnetic field. The layers can also be categorized into the rigid outer lithosphere (which includes the crust and top portion of the mantle and makes up Earth's tectonic plates) and the athenosphere, the portion of the mantle that is solid, but made up of hot, weak, flowing rock. Read about the latest research on Earth's layers below.
Earth may have had a protective magnetic field earlier than previously thought, generated not by its liquid outer core as happens today, but by a magma ocean sitting above the core, a new study suggests.