Moon Study Guide
Important Vocabulary:
Axis of Rotation - An imaginary line going from the north pole to the south pole. The earth
spins on this line.
Earth’s Tilt ­ The earth’s axis is not straight up and down, instead it leans at a 23.5-degree
angle.
Orbit - The path that a planet travels as it goes around the sun.
Phases of the Moon - The changes in the appearance of the moon’s shape during a month.
Reflection - The bouncing of light off of an object. The moon appears to shine because it
reflects the sun’s light. Revolution - The circling of one object around another object in space. A planet revolves
around the sun. A moon revolves around a planet.
Rotation - When a planet or moon turns all the way around or spins on its axis one time.
Important Concepts:
1. The length of a moon cycle is 28 days and each phase is approximately 3.5 days.
2. There are eight phases of the moon: New moon, Waxing Crescent, First Quarter Waxing
Gibbous, Full Moon, Waning Gibbous, Third quarter, Waning crescent.
3. The Earth rotates on it’s axis and revolves around the sun and the moon revolves around the
Earth.
4. Based on where the position of the earth is relative to the sun is what determines each moon
phase
5. Earth takes one day and one night to complete a rotation on its axis.
Sample Questions:
1. What is the movement of Earth
around the sun called?
a. precipitation
b. random movement
c. revolution
d. rotation
Answer: Revolution
2. What causes the apparent movement of the sun across the sky during the day on
Earth?
a. revolution of Earth in its orbit
b. rotation of Earth on its axis
c. location of Earth in space
d. objects are moving around Earth
Answer: Rotation of earth on its axis
3. Which of the following correctly describes the movement of Earth, Moon and sun?
a. Sun revolves around Moon, Moon revolves around Earth
b. Sun and Moon revolve around Earth
c. Moon revolves around sun, Earth revolves around Moon
d. Moon revolves around Earth, Earth revolves around sun
Answer: moon revolves around Earth, Earth revolves around sun
4. What is the movement of Earth on its axis called?
a. rotation
b. phases
c. floatation
d. revolution
Answer: Rotation
5. If a complete Moon cycle takes approximately 28 days, about how many days during
a month could you expect to see a crescent Moon?
a. 1
b. 2
c. 7
d. 13
Answer: 13 ( this one is tricky, it is also counts the waxing and waning gibbous as
crescents)
6. If you saw a full Moon last night what Moon would you see in a week?
a. First quarter Moon
b. Third quarter Moon
c. Waxing crescent Moon
d. New Moon
Answer: Waxing Crescent
7. Why doesn't the Moon shine as bright as the sun?
a. The Moon is much smaller than the sun.
b. The Moon shines at night and the sun shines during the day.
c. The light from the Moon is reflected light from the sun.
d. The sun is farther from the Earth.
Answer: The moon reflects light from the sun
8. What is the name of the phase of this Moon?
a. Waning Crescent
b. Waxing Crescent
c. Waning Gibbous
d. Waxing Gibbous
9. Why doesn't the Moon shine as bright as the sun?
a. The Moon is much smaller than the sun.
b. The Moon shines at night and the sun shines during the day.
c. The light from the Moon is reflected light from the sun.
d. The sun is farther from the Earth.
10. What is the name of the phase of this Moon?
a. Waning Crescent
b. Waxing Crescent
c. Waning Gibbous
d. Waxing Gibbous
Answer: waxing crescent
11. The same side of the Moon always faces the Earth. How is this possible?
a. The Moon has a heavier side to it causing it to always face the Earth.
b. The Moon doesn’t rotate causing it to always face the Earth.
c. The Moon doesn’t have gravity causing it to always face the Earth.
d. It is not possible for the Moon to always face the Earth.
Answer: The moon does not rotate causing it to always face the Earth.
12. What phase is this Moon in? Use the diagram below
a. New Moon
b. Waning Crescent Moon
c. Waxing Crescent Moon
d. Full Moon
Moon
Earth
Sun