1. Earth

2. Models Model is a representation of an object or event.

3. Shape of Earth Earth is “fat” at the center! It is not a circle or sphere! Oblate Spheroid

4. How do we know the Earth is round“ish” ? When I look at the sky the sun rises and sets! Stars appear to rise and set! When I look in the distance it is flat! Prove it how do we know it’s shape.

5. Proof Sinking Ship Theory – Back in the day (a Tuesday-btw) when ships would leave port the families would watch the ship sink in the distance, only to find out that they were fine!

6. Proof Gravity – Because Earth is not perfectly round the amount of pull the Earth has (gravity) varies. At the poles you weight more At the Equator you weight less

7. Proof Pictures – Our best evidence is pictures from space!

8. Proof Shadows on the moon (eclipse) – As the Earth blocks the sun a shadow appears on the moon.

9. Structure of Earth Lithosphere – Crust and rigid mantle ends at the MOHO. Hydrosphere – All liquid layer on the surface of the earth. Atmosphere – Shell of gas around the surface.

10. Layers of Earth Lithosphere: Crust and rigid mantle ends at the MOHO. 2.7-3.0g/mL 5-60km deep. Mantle: Asthenosphere or plastic mantle 60- 2900km deep. Outer Core: 2900-5100km deep made of liquid iron and nickel. Inner Core: 5100-6300+km made of solid iron and nickel.

11. Layers of the Earth

12. ESRT Chart Earth’s LayerTemperature Range (oC) Pressure Range (million ATM) Density Range (g/mL) Depth Range (km) Crust (lithosphere) (Solid) Mantle (Solid”ish”) Outer Core (liquid) Inner Core (Solid)