Name______

MOON PHASES

Introduction:The Moon, Earth’s natural satellite, appears to rise in the east and set in the west. As you know, this is a result of the Earth’s rotation from west to east. The Moon also appears to change shape during the month in a predictable pattern. The apparent shape change is due to the Moon’s ~28 day revolution around the Earth. In this lab you will see the Moon in several of its positions around the Earth and understand the reason for the apparent change in shape of the Moon. In addition, you will compare the Moon’s period of revolution around the Earth to the Earth’s period of revolution around the Sun. You will understand how the phases of the Moon relate to the position of the Moon relative to the Sun and Earth. You will also understand why we always see the same side of the Moon, and what rotation and revolution have to do with it.

Procedure A:Refer to Diagram 1 on the next page.

1. Lightly shade the half of the Moon that would be in darkness. (this is the side facing AWAY from the Sun).

2. Lightly shade the half of the Moon that you CANNOT see from the EARTH (this is the side outside the Moon’s orbit).

3. The Moon revolves around the Earth in the same direction that the Earth rotates. Use arrows to show the direction of revolution along the Moon’s orbit.

4. Refer to the pictures below to correctly label that name of the phase for each position on diagram 1.

5. Answer the questions.

Diagram 1

Sunlight

Sunlight

Sunlight

Questions:Refer to Diagram 1 to answer the following questions. Answer using the numbered position that the Moon is in.

  1. ______During this phase the Moon is NOT visible from Earth.
  2. ______During this phase the Moon appears to be COMPLETELY lighted from Earth.
  3. ______During this phase the Moon appears to be half-lighted from Earth.
  4. ______What is the motion of the Moon that causes it to have phases?
  5. ______At what time of day would an observer have the new Moon cross their celestial

meridian? (position A)

  1. ______At what time of day would the full Moon cross the observer’s celestial meridian?
  2. ______At what time of day will the first quarter Moon be at the observer’s celestial

meridian?

  1. ______At what time of day will the last quarter Moon be at the observer’s celestial

meridian?

  1. ______In which direction will the Full Moon appear to rise?
  2. ______In which direction will the First quarter Moon appear to set?
  3. ______At which positions would an observer on Earth experience Spring tides?
  4. ______&______At which positions would an observer on Earth experience Neap tides?
  5. ______During this phase of the Moon an observer on Earth is able to view a Solar

Eclipse?

  1. ______During this phase of the Moon an observer on Earth is able to view a Lunar

Eclipse?

15. In the space below, sketch the position of the Earth, Moon and Sun TODAY. You may have to look

this up on the internet or in the newspaper.

Procedure B:Refer to Diagrams 2 and 3 on the next page.

1. Each lab group will receive 8 Oreo cookies and a sheet of paper.

2. Carefully separate your cookies so only ONE side/half has all the frosting and the other has NO frosting.

3. Use a plastic spoon/knife to scrap off the frosting from the first cookie to make a shape that resembles the cookie shown below. This represents the moon in a Waxing Gibbous Phase.

4. Repeat step 3 with the other cookies; scraping the frosting into the shape of the remaining phases as seen from Earth. You will have to create waxing and waning phases.

5. Place your cookie Moon phases on Diagram 3 in the correct positions. You must refer to Diagram 2 which shows the Moon’s position in its orbit. Match up the positions on Diagram 3 to those on Diagram 2 and place your cookies in the correct position. Remember to start at Position 1 and work in a counterclockwise motion according to Diagram 3.

6.On Diagram 3 label each of the phases in order from Position 1 to Position 8

Diagram 2

Diagram 3 – The Earthlings View of the Moon (place your cookie moons here)

______

Position 1 Position 2 Position 3Position 4

______

Position 5 Position 6 Position 7Position 8

Questions:

1.How long is one cycle of Moon phases? ______

2. What is the average time (in days) between phases? ______

3. Describe the processes that cause the Moon to appear in different phases to Earthlings.

4. What is the greatest number of Full-Moon phases that can occur over a one year period? ______

5. The small, white circle on each of the Moon’s in Diagram 2 represents the Impact Crater “Tycho”. Tycho formed about 108 million years ago and is one of the youngest craters on the Moon. It was named after the famous astronomer Tycho Brahe. Explain why this crater ALWAYS faces the Earth.

6. Referring to Diagram 2, when would an observer on Earth see an Eclipse?

Solar Eclipse ______; Position _____ Lunar Eclipse _______; Position _____

This diagram below shows the positions of the Moon and Sun at sunset during an evening in New York State. Points A, B, C and D represent positions along the Western Horizon

.

7. At which position will the Moon be located the Following evening at Sunset? ( A B C D ) ?