How's your knowledge of Earth's geology? Flat, round or global?

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 ...

Over time, they noticed that the atmosphere had distinct layers. By the early 1900s ... Here are scientists’ plans Earth’s atmosphere remains stable enough for life to flourish, but it ...

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 ...