The structure of the Earth is divided into layers. These layers are both physically and chemically different. The Earth has an outer solid layer called the crust, a highly viscous layer called the mantle, a liquid layer that is the outer part of the core, called the outer core, and a solid center called the inner core. https://simple.wikipedia.org/wiki/Structure_of_the_Earth
The Merge Object Viewer app is required to view this object