Earth’s Moon
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Printed: August 29, 2014
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C HAPTER
Chapter 1. Earth’s Moon
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Earth’s Moon
Lesson 24.2: True or False
Name___________________ Class______________ Date________
Write true if the statement is true or false if the statement is false.
_____ 1. Astronauts first walked on the moon in 1969.
_____ 2. The moon is about one-third the size of Earth.
_____ 3. The same side of the moon always faces Earth.
_____ 4. The far side of the moon has a thinner crust and more maria.
_____ 5. The moon gives off no light of its own.
_____ 6. The far side of the moon has been seen only by spacecraft.
_____ 7. The moon’s surface temperature is always very low.
_____ 8. Volcanic activity ceased on the moon more than a billion years ago.
_____ 9. The moon has several high mountain ranges.
_____ 10. There is evidence of ancient life on the moon.
Lesson 24.2: Critical Reading
Name___________________ Class______________ Date________
Read this passage based on the text and answer the questions that follow.
The Lunar Surface
The moon has no atmosphere. Because an atmosphere moderates temperature, the moon’s average surface temperature has a lot of variation. During the day, the surface temperature averages about 225 degrees F, but it drops to
-243 degrees F at night. The coldest temperatures on the moon, at around -397 degrees F, occur in craters in the
permanently shaded south polar basin. These are among the coldest temperatures recorded in the entire solar system.
The landscape of the moon is unchanging. With no plate tectonics, new surface features are not built. With no
atmosphere, existing surface features are not weathered away. A major type of surface feature on the moon is
craters, which are caused by meteorite impacts. Most of these occurred at least a billion years ago, but because there
is no weathering, the craters still look as they did when they first formed.
Even without a telescope, you can see from Earth that the moon has dark-colored areas and light-colored areas. The
dark-colored areas are called maria, and they cover about 16 percent of the moon’s surface, mostly on the near side
of the moon. The term maria means “seas,” because people long ago thought the dark areas were seas of water,
like those on Earth. However, the maria are not areas of water but areas of flat basaltic rock. From about 3.0 to 3.5
billion years ago the moon was continually bombarded by meteorites. Some of these meteorites were so large that
they broke through the moon’s newly formed surface. Then magma flowed out and filled the craters, forming the
basaltic maria. Scientists estimate that this activity ceased about 1.2 billion years ago.
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The light-colored parts of the moon are called terrae, or highlands. Terrae have higher elevations than maria and
include several high mountain ranges. Terrae consist of light silicate minerals that precipitated out of the ancient
magma ocean and formed the early lunar crust.
There are no lakes, rivers, or even small puddles of liquid water anywhere on the moon’s surface. However, this
doesn’t mean that the moon lacks water. Frozen water has been found in the extremely cold craters of the moon and
also bound up in the lunar soil.
Questions
1.
2.
3.
4.
Explain why surface temperatures on the moon vary from extremely hot to extremely cold.
Why is the landscape of the moon unchanging?
Compare and contrast maria and terrae on the moon’s surface, including how each type of feature formed.
Where and in what state is water found on the moon?
Lesson 24.2: Multiple Choice
Name___________________ Class______________ Date________
Circle the letter of the correct choice.
1. Areas on the moon called maria
a.
b.
c.
d.
are seas of water.
consist of basaltic lava.
formed a million years ago.
two of the above
2. The surface of the moon includes
a.
b.
c.
d.
craters.
mountains.
polar ice caps.
two of the above
3. The moon’s core
a.
b.
c.
d.
is relatively small.
contains very little iron.
consists mostly of nickel.
is composed of igneous rock.
4. The mantle of the moon
a.
b.
c.
d.
is composed of two layers.
may have high levels of iron.
contains the mineral olivine.
all of the above
5. The moon’s crust is rich in the elements
a.
b.
c.
d.
silicon.
oxygen.
magnesium.
all of the above
6. For the moon to make one complete rotation, it takes about 4
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a.
b.
c.
d.
Chapter 1. Earth’s Moon
hours.
days.
weeks.
none of the above
7. The moon has no
a.
b.
c.
d.
water.
atmosphere.
plate tectonics.
two of the above
Lesson 24.2: Matching
Name___________________ Class______________ Date________
Match each definition with the correct term.
Definitions
_____ 1. dark-colored, flat areas on the surface of the moon
_____ 2. relating to the moon
_____ 3. the moon’s innermost layer
_____ 4. amount of time it takes the moon to make one complete revolution
_____ 5. bowl-shaped depression caused by a meteorite impact
_____ 6. light-colored, highland areas on the surface of the moon
_____ 7. the moon’s outermost layer
Terms
a. orbital period
b. crust
c. crater
d. lunar
e. maria
f. core
g. terrae
Lesson 24.2: Fill in the Blank
Name___________________ Class______________ Date________
Fill in the blank with the appropriate term.
1. Earth’s only natural satellite is the __________.
2. The moon orbits Earth because of the force of __________.
3. The moon is __________ dense than Earth.
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4.
5.
6.
7.
Earth’s gravity is __________ times greater than the moon’s gravity.
The moon’s orbital period is __________ days.
We can see the moon from Earth only because it __________ light from the sun.
Features on the moon’s surface do not wear down because the moon has no __________.
Lesson 24.2: Critical Writing
Name___________________ Class______________ Date________
Thoroughly answer the question below. Use appropriate academic vocabulary and clear and complete sentences.
The footprints of astronauts in dust on the moon will remain undisturbed for as long as the moon exists unless they
are struck by a meteorite. Explain why.
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