What is inside the middle of the Earth?

The question “What is inside the middle of the Earth?” comes from Ms. Thelen’s class.

If you spend time playing in the dirt, you have probably noticed that there are different types. When you drive by cliffs on the highway, you can see layers which continue throughout the inside of the Earth, all the way to the core. What is it made of?

The center of the Earth is about 4,000 miles below the surface. We’ve never studied the core directly, but scientists can learn about it by studying other rocky planets. Based on these observations, scientists hypothesize that Earth’s core is about 80 percent iron, with small amounts of nickel. The innermost part of the core is solid, but the outer core is a molten liquid consisting of iron, nickel, and other light elements.

The next layer is the mantle, which has more magnesium than the core. High temperatures cause it to act like a viscous liquid. Movement in the mantle causes tectonic plates to move, which results in earthquakes. The crust is the last layer of the Earth and is what we interact with every day. The crust is made mostly of basalt and granite and is cooler and more rigid than the lower layers.

Fun fact: Lava in volcanic eruptions often comes from the molten rock, called magma, in the Earth’s mantle.

Ronnie LaCombe is a biology graduate student at the University of Missouri.