Post on 30-Jun-2015
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Ch. 1Ch. 1Sec. 4 Earth’s MoonSec. 4 Earth’s Moon
Activity-Why do craters look Activity-Why do craters look different from each other?different from each other?
Object Object Diameter of Diameter of circle- 20 cmcircle- 20 cm
Diameter of Diameter of circle- 50 cm circle- 50 cm
Diameter of Diameter of circle- 100 cmcircle- 100 cm
(1 m)(1 m)
Small Small marblemarble
Large Large marblemarble
Rubber Rubber ballball
Which object left the largest crater? Which object left the deepest crater?
Features on the moon’s surface include craters, highlands, and maria.
Astronomers have given names to many of the moon’s craters and maria.
features onMoon’s surfaceseen by Galileowith telescope
craterscraters highlandshighlands mariamaria
round pits formed by
meteoroid impactsnot volcanoes
mountains• dark, flat areas-ancient lava flows• once thought to be ancient seas
Ocean of
Storms
Sea of Tranquility
Mooncharacteristics
size & size & densitydensity
temp. & temp. & atmos.atmos. waterwater
• ¼ Earth’s diameter
•1/80 Earth’s mass
130oC -180oC
dry & airless
• no liquid water• may have ice
No atmosphere
collision-ring theorycollision-ring theory
best theory of moon’s originbest theory of moon’s origin
1.1. 4.5 billion yrs. ago- planet 4.5 billion yrs. ago- planet sized object hit Earth sized object hit Earth
2. material from Earth’s outer 2. material from Earth’s outer layer broke off layer broke off 3. material thrown into orbit3. material thrown into orbit4. formed moon4. formed moon
Time to Time to ReviewReview
Name 3 major features of Name 3 major features of the moon’s surface.the moon’s surface.
1.1. craterscraters
2.2. mariamaria
3.3. highlandshighlands
How did the moon’s How did the moon’s craters form?craters form?
meteoroid meteoroid
impactsimpacts
Why is the moon’s surface Why is the moon’s surface much more heavily cratered much more heavily cratered
than Earth’s surface?than Earth’s surface?
Water, wind, and other Water, wind, and other forces wore away craters on forces wore away craters on Earth. There is no wind or Earth. There is no wind or liquid water on the moon.liquid water on the moon.
Describe the range of Describe the range of temperatures on the moon.temperatures on the moon.
130oC to -180oC
(266oF to -292oF)
What is the relationship What is the relationship between the moon’s surface between the moon’s surface
gravity, lack of an atmosphere, gravity, lack of an atmosphere, and temperature range?and temperature range?
The moon’s weak surface gravity The moon’s weak surface gravity allows gases to escape into allows gases to escape into space, so the moon has no space, so the moon has no
atmosphere, resulting in widely atmosphere, resulting in widely varying surface temperatures.varying surface temperatures.
What was the solar What was the solar system like when the system like when the
moon formed?moon formed?
The solar system was The solar system was full of rocky debris.full of rocky debris.
Explain the various stages in Explain the various stages in the formation of the moon.the formation of the moon.
1.1. A planet-sized object collided A planet-sized object collided with Earth. with Earth.
2.2. Material was ejected into orbit Material was ejected into orbit around Earth and formed a ring. around Earth and formed a ring.
3.3. Gravity caused this material to Gravity caused this material to combine into the moon.combine into the moon.