The Moon

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The Moon
Satellite Any body orbiting a central mass
No Atmosphere No temperature regulation Daytime
temperature 400 K (266 F) Nighttime
temperature 100 K (-280 F)
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Moon Facts

• Moons Period- 29.5 days
• Moons Day- 29.5 days
• Distance- 250,000 miles
• Gravity- 1/6th that of the earths. 120 pound
  weight on the earth would weigh about 20 pounds
  on the Moon.

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Atmosphere of the Moon

• The moon has no atmosphere
• Not really. About half of the present atmosphere
  of the Moon is from the exhaust of the Apollo
  Moon Missions!
• Therefore, there is no weather on the moon.
• No atmosphere means that wings (airplanes,
  helicopters, etc.) and parachutes wont work.
• It also means that there is essentially no
  protection from x-rays and micrometeorites on the
  Moons surface as there is on the earth.

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Surface Features
Craters Mare - Dark, smooth lava filled
regions Highlands - lighter colored, rough
terrain Mountains - actually crater rims or
sections of crater walls Volcanic features
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Mare tend to have circular edges large impact
basins that filled with lava
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Areas without mare Heavily cratered highlands
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Impact made basin (bowl shape) Lava filled basin
creating mare Later impacts occurred Mare are
younger (newer) than highlands
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Faults
Rille
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Structure of the Moon
Composition of the Moon similar to the Earths
Mantle Very little metal (iron, nickel), mainly
rock
Crust
Mantle
Iron-rich core
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Lunar Crust
Near side
Far side
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Thinner crust on Near Side allows formation of
Mare
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Gravity of the Moon

• The earths gravity pulls the moon and keeps it
  in orbit. (Without its motion, the moon would
  fall down to the earth. Without the earths
  gravity, the Moons motion would cause it to
  leave the earth.)
• Does the Moons gravity pull on the earth? Are
  there any effects that we can see if the Moon
  does in fact pull on the earth?

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Gravity of the Moon Tides

• What are tides, and what causes tides?
• Are some tides bigger than others?
• Is it in any way related to either the sun or the
  Moon?
• We will try to answer the first question AFTER we
  answer the other three.

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Tides

• Caused by the gravitational interaction between
  the Earth and the Moon. The gravitational
  attraction of the moon causes the oceans to bulge
  out in the direction and opposite direction of
  the moon.

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Spring Tides

• Spring tides- Strong Tides occur when the Earth
  moon and sun align (has nothing to do with the
  season Spring)

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Neap Tides

• Neap tides- Weak tides that occur when the
  gravitational forces of the Moon and the Sun are
  perpendicular to one another

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Tidal Effects
The Earths pull slowed the rotation of the Moon
(Tidally locked) The Moons pull is slowing the
rotation of the Earth
(by about 0.7 seconds/year) The Earths pull in
also slowing down the Moons orbital velocity -
the Moon is getting further from the Earth by 3.8
cm/year Far in the future, the Moon will be very
far from us, one side of the Moon will face one
side of the Earth
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Apollo Mission 6 lunar landings 12 people walked
on the Moon (and played golf) 850 pounds of rocks
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All near side landings Lunar Rover
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Lunar Rocks
Basalts - found in the mare, volcanic
Anorthosites - highlands, aluminum, calcium,
silicates
Breccia - cemented rocks
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Origin of the Moon
History of the Moon - Impact Theory- 4.5
billion years ago A very large asteroid hit earth
with enough force to break a chunk of earth off
which was caught in the earths orbit and became
the moon. - Moon has a similar mantle composition
as earth