1. BY: RANDI ANGELL MARY BLOOR HEIDI DARDINGER The Structure of the Earth

2. Terrestrial Planets: Mercury, Venus, Earth, Mars Characteristics:  3 compositional layers: crust, mantle, and core  Core composed of rock and nickel mixture  Composition similar to a meteorite

4. Layers:

5. The Crust: Outer most layer of the Earth In the oceans, it is about 4 miles thick On the thickest continents, it can be up to 40 miles thick The Mantle: 1,800 miles thick Weaker and hotter rock than the crust Oxygen, Silicon, and Magnesium

6. Apple Analogy: Think of the earth as an apple. The outer skin of the apple is the crust. The inside part, the fruit that you eat, is the mantle. And the core of the apple is the earth’s core.

7. The Inner Core: 1,300 miles thick Liquid Iron The Outer Core: Sphere at the center of the earth 1,500 miles across Solid iron

8. Volcanic Activity: Evidence that the internal heat of the earth is being maintained. Heat is being transferred from the core to the surface. Heat is moved in the mantle through:  Conduction  Convection

9. Why is There Life on Earth?: Liquid Water Gravity Protective Atmosphere Life-Sustaining Gases

10. The structure of our planet gives it many of it’s unique characteristics which are responsible for the presence of human life on Earth!