Transcript Earth and Moon

Earth and Moon
Our home and
our nearest neighbor
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Earth-Moon System
• Distance from the earth to
the moon:
– 384,000 km
– Less than the radius of the
Sun (696,000 km)
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Tides
Synchronous
rotation
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The Earth’s Interior
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How do we know what the
Earth looks like inside?
• Seismology
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Differentiation and Heat
• A differentiated planet
is not the same all the
way through. A
homogeneous planet is
the same.
• Heating a planet
allows movement.
• Heavier materials sink
to the inside and
lighter materials rise.
Sources of
Heat
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The Earth’s Surface
• 70% water, 30% rock
• Continental crust is less dense than oceanic crust
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Rocks
• Rocks are
made of
minerals
• Types of rocks:
– Igneous rocks are those that have formed from a
molten state (volcano made)
– Sedimentary rocks are composed of fragments
of other rocks that are cemented together (water made)
– Metamorphic rocks are produced from either igneous
or sedimentary rocks that have been buried and
modified by high temperatures and pressures
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Why does the earth look like this?
Processes that alter the
surface of the earth:
• Endogenic
– Forces that act from
inside the earth:
• Volcanic
• Erosional
• Tectonic
– These forces can make
rocks
• Exogenic
– Forces that act from
outside the earth:
• Cratering
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Tectonics
Any movement of
the earth
–
–
–
–
Folding
Fracturing
Earthquakes
Plate tectonics
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Plate Tectonics
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Volcanoes
Spreading
centers
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Volcanoes
Converging plate
margins
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Volcanoes - Hotspots
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Volcanoes
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Erosion
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Atmosphere
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Atmosphere
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Terrestrial
greenhouse
effect
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Magnetosphere
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Moon - Interior
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Moon - Surface
Lunar rocks are mostly igneous
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Lunar
surface
features
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Origin of the moon
• Current theory –
planetesimal hits
protoplanetary earth
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Lunar exploration
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