3. Explain that the Earth is made of three main layers: crust, mantle, and core. Draw them on the board using colored chalk. Explain that the core is divided into two layers: solid inner core and ...

It's the thinnest of Earth's three main layers, yet humans have never drilled all the way through it. As you descend, you'd soon reach the depth of the Paris Catacombs, the deepest metro station ...

These days, I’m a geophysicist and know a lot more about Earth’s structure. It has three main layers: The outer skin, called ...

Over time, they noticed that the atmosphere had distinct layers. By the early 1900s, scientists had identified major layers of the ... and keep temperatures on Earth habitable for all living ...