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 ...

Project: Earth takes a deep dive into the environmental science issues that impact our daily lives. Host Hales Parcells gives viewers an in-depth look at the issues that affect our world ...

There's a lot more to Earth than meets the eye. Far from being just a roundish rock barreling through space, our planet is composed of several layers held together by intense forces of gravity.