1. Earth’s Formation

2. Layers of the Earth What is in the center of our Earth? What do we stand on? What fills up the holes in our Earth? What is above us?

4. How do scientists know what is inside Earth? Earthquakes –E–Earthquakes transmit energy and we can measure that energy to “see” Earth’s interior –T–These waves change speeds when they go through materials of different densities How do earthquakes transmit energy? –V–Via seismic waves

5. Other Evidence Average density of the Earth Composition of meteorites Earth’s magnetic field

6. What we found We found out our Earth has layers! Just like your baby food jar model. And why does the Earth have layers??? –B–Because of differences in density

7. Earth’s Formation http://www.bbc.co.uk/science/earth/earth_ti meline/earth_formed#p00fzslq http://www.bbc.co.uk/science/earth/earth_ti meline/earth_formed#p00fzslq

8. Mesosphere

9. Crust Thin, but rigid top layer Made up primarily of basalt rock (ocean) and granite rock (continents) – The oceanic crust is denser then the continental rock!

11. Mantle Partially molten rock that can flow Makes up 68% of the mass of the Earth

14. Core Made up of nickel and iron, which makes this layer magnetic and very dense Divided into layers – Outer Core: liquid – Inner Core: solid

16. But wait, there’s more... The Earth has layers due to density differences, above the crust, though, what do we encounter? Gas has mass and can be confined to a volume, so is there layers to our air? – Yes, yes there is

17. Our Atmosphere

18. Layers of the Atmosphere pg. 55 Troposphere: only layer that has weather, contains 90% of the mass Stratosphere: where airplanes fly Mesosphere: coldest layer (0 C to -90 C)

19. Layers of the Atmosphere (cont) Thermosphere: technically hot, but it would feel cold to us Exosphere: blends into space REMEMBER: The atmosphere has layers because of density differences, just like our Earth!