The Moon
The Moon is earth’s only natural satellite. It is one the brightest objects in our sky. The moon appears in
many different shapes over the course of a month. These observed shapes are all a result from the interaction
of the Moon’s orbit around Earth and the sunlight that is reflected off of its surface.
View from the Earth
A
B
Position
A
B
C
D
E
F
G
H
C
D
E
Phase Name
F
G
H
ü Exercise #8 – The Moon
Directions:
1. Answer the following questions in complete sentences based on the flash animation and your
drawings of the Moon on the previous page.
1. In which direction is the Earth rotating on its axis? Which direction is the Moon revolving around the Earth?
2. The Moon does not produce its own light. Explain why it is possible for us to see the Moon from Earth.
3. What is the name of the phase we have when the Moon is between the Earth and Sun?
4. What is the name of the phase we have when the Earth is between the Moon and Sun?
5. Approximately how long is the lunar cycle?
6. What term is used to describe when the illuminated portion of the moon is increasing? Decreasing?
7. Based on the video depiction, explain why we only see one side of the Moon.
ü Exercise #9 – Moon Reinforcement Questions
Base your answers to questions 1 and 2 on the diagram below, which shows Earth in orbit around the Sun, and
the Moon in orbit around Earth. M1, M2, M3, and M4 indicate positions of the Moon in its orbit.
Letter A indicates a location on Earth’s surface.
1. An observer at location A on Earth views the Moon when it is at position M3. Which phase of the Moon will
the observer see?
2. An observer at location A noticed that the apparent size of the Moon varied slightly from month to month
when the Moon was at position M4 in its orbit. Which statement best explains this variation in the apparent size
of the Moon?
(1) The Moon expands in summer and contracts in winter.
(2) The Moon shows complete cycles of phases throughout the year.
(3) The Moon’s period of rotation is equal to its period of revolution.
(4) The Moon’s distance from Earth varies in a cyclic manner.
3. Diagram 1 shows the Moon in its orbit at four positions labeled A, B, C, and D. Diagram 2 shows a phase of
the Moon as viewed from New York State.
At which labeled Moon position would the phase of the Moon shown in diagram 2 be observed from New York
State?
(1) A
(2) B
(3) C
(4) D
Base your answers to questions 4 through 7 on the diagram below, which shows Earth as viewed from above the
North Pole. The nighttime side of Earth has been shaded. The Moon is shown at eight positions in its orbit
around Earth. The name of each Moon phase is indicated at each Moon position. The dark portion of each
Moon position has not been shaded.
4. On the diagram below, shade the portion of the Moon that is in darkness to show the last quarter phase as
viewed from New York State.
5. Explain what causes the Moon’s phases when viewed from Earth.
6. Which Moon phase occurs approximately one week after the New Moon phase?
7. Explain why the same side of the Moon always faces Earth.
ü Exercise #11 – Tides
A. High and Low Tides
Because the moon is close to the earth, there are interactions between the earth and the moon.
One visible interaction is the effect of the ________________________________ of the moon on the earth.
This pull results in the _________________________________ as the moon moves in its orbit around the earth.
The rise and fall of the oceans are called ____________________.
1. In figure 1, which side of the earth is facing the moon? ___________________________
2. Which sides of the earth are having high tide? ____________ low tide? _____________
3. In figure 2, which sides of the earth are having high tide? _____________ low tide? ____________
4. How much time has passed between Figures 1 and 2? ________________________________
5. In figure 3, which sides of the earth are having high tide? _____________ Low tide? ____________
6. How much time has passed between Figures 2 and 3? _________________________________
B. Spring Tides
When the moon is at its full and new phases, the earth has higher high tides and lower low tides than at other
times. These tides are called spring tides and they happen twice a month. They occur when the sun and the
moon line up with the earth. The increased effect of the sun’s gravity on the earth causes the ocean bulges to
become larger.
1. During which p hases of the Moon do spring tides occur? ____________________________________________
____________________________________________ 2. What happens to the pull of gravity on Earth when the Sun, Earth, and Moon are in a line? ____________________________________________
____________________________________________ 3. What are the unusually high and low tides called?__________________________________ 4. Approximately how often do the unusually high and low tides happen?____________________________________
___________________________________________ C. Neap Tides
During the first and last quarter phases, the moon’s gravitational pull on the oceans is partially canceled out
by the sun’s gravitational pull. This results in tides that are not very high and not very low. These tides arc
called neap tides and they happen twice a month.
1. During which phases of the moon do neap tides occur? ____________________________________________
____________________________________________ 2. What happens to the pull of gravity when the Sun, Earth, and Moon are at right angles? ____________________________________________
____________________________________________ 3. What are tides that are not very high and not very low called? ____________________________________________ 4. Approximately how often do “not very high tides and n ot very low tides” occur? ____________________________________________
____________________________________________ ü Exercise #10 – Eclipses
Directions:
1. Answer the following questions in complete sentences.
Every so often the Sun, Earth, and Moon align on a perfectly flat plane. When this occurs the Moon may
block out the Sun's light from reaching the Earth or the Earth may block out the Sun’s light from hitting the
Moon. These rare events are referred to as solar and lunar eclipses.
SOLAR ECLIPSES
1. Explain what needs to happen in order for a solar eclipse to occur. Draw a sketch to accompany your answer. (Be sure to label
the Sun, Earth, and Moon.)
2. Imagine If the tilt of the Moon’s orbit was lowered 15 degrees explain what you would observe. What do you think would happen
to the amount of solar eclipses we can observe from earth?
3. Imagine if we increased the distance between the Earth and the moon. What do you see? How would this movement effect solar
eclipse?
LUNAR ECLIPSES
4. Explain what needs to happen in order for a lunar eclipse to occur. Draw a sketch to
accompany your answer. (Be sure to label the Sun, Earth, and Moon.)
5. Imagine if we increased the distance between the Earth, Moon and the Sun. What do you
see? How would this movement effect solar eclipse? Draw a sketch to help you answer the
question.
7. Why don’t eclipses occur during every new moon and full moon?