Proof the earth is ROUND
Fresh water:
1%
Ice:
2%
Oceans:
97%
Gravity:
A force of attraction
Photos of the earth from space
Best way of knowing the shape of the earth
Inner earth
Determined by studying earthquakes
Mantle
Hard rock
Sextant:
Instrument that measures the altitude of polaris
Gravity depends on....
Mass and distance
Outer core
Melted iron (liquid)
Asthenosphere
Melted rock
The height polaris changes as you go....
North or south
Polaris
North star
Ships appear to disappear as they sail away because...
Sailing around the curved surface of the earth
Inner core
Solid iron
Crust: lithosphere
The crust and the upper mantle that form an outer shell around the earth
Atmosphere
The layer of gas that surrounds the earth
Hydrosphere
The layer of liquid water that rests on the crust
The altitude of polaris is....
Your altitude