| A | B |
|---|
| oblate spheroid | slightly flattened sphere |
| 40,007 km | Earth's pole to pole circumference |
| 40,074 km | Earth's equatorial circumference |
| 12,756 km | Earths diameter |
| seismic waves | vibrations that travel through the Earth |
| crust | thin, solid, outermost zone of the Earth |
| oceanic crust | crust that is located under the oceans |
| global ocean | thin layer of water that covers the Earth |
| continental crust | crust that makes up the continents |
| moho | the lower boundary of crust |
| mantle | the denser layer that underlies the crust |
| core | sphere made of nickel and iron that is at the center of the Earth |
| lithosphere | cool, brittle part of the upper mantle |
| asthenosphere | solid yet plastic layer of mantle which has the ability to flow as a solid |
| mesosphere | solid mantle rock found below the asthenosphere |
| outer core | liquid core |
| inner core | solid core |
| magnetosphere | the region of space that is affected by the Earth's Magnetic field. |
| gravity | the force of attraction that exists between all matter in the universe |
| law of gravitation | states that the force of gravity depends on the mass of the objects and the distance between them |
