GET FOCUSED

During Investigation Three, students will use a model of the Earth, Moon, and the Sun to observe the different phases of the Moon during its revolution around Earth.

INVESTIGATE

1. Guide students in setting up the model they will use for Trials 1 – 4.

a. Instruct students to place one stool in the center of their work area.

b. Tell students that they will place four pieces of tape around the stool, one in front, one behind, and one on either side. Students should use the meter stick to make sure that each piece of tape is 1 m from the stool.

c. Instruct each group to label the piece of tape toward the back of the classroom with a 1. Students should continue numbering the pieces of tape in a counter-clockwise fashion.

d. Ask one student in each group to sit on the stool. This student represents Earth in the model. Have the student hold a small globe.

e. Ask another student to stand on the piece of tape labeled 1. This student should hold the moon ball above his or her head. The Moon ball represents the Moon.

f. Instruct students to place one small piece of tape on the side of the Moon that faces the Earth. This tape is to remind students which side of the Moon is the side near the Earth.

Trial 1

During this Trial, students will begin to use the model of the Earth and the Moon. The student representing the Earth will slowly turn around on the stool seven times while staying seated. While the student is turning, the student representing the Moon will slowly begin revolving around the Earth. Onlookers may help the student on the stool count to seven. At the end of seven of the Earth’s rotations, the Moon will be standing on the second piece of tape. This will help students answer the question:

How is the rotation of the Earth related to the revolution of the Moon?

Trial 2

During this trial, students will model the Sun’s illumination of the Moon. To do this, students will add a model Sun by way of a student holding a flashlight. Students will model the illumination of the Moon during New Moon. Students should record their observations of the Moon as though they are observing from Earth. If necessary, encourage students to take turns standing behind the Earth so that they can all observe the Moon from this perspective before recording their observations.

Although students will observe the position of the Moon at New Moon, they will simply refer to this position as Position 1. During the analysis conducted during Post-Lab, students will describe and label the phases they observed in Trials 2 – 5. This Trial guides students toward answering the question:

How does the Moon appear at Position 1?

NOTE: In order to keep the person representing the Earth from becoming dizzy, the student representing the Earth does not need to model the seven rotations between phases of the Moon during Trials 2 – 5. Explain to students that even though they are no longer modeling the rotation of the Earth, it continually occurs in the Solar System.

Trial 3

During this trial, students will again model the Sun’s illumination of the Moon. This time, students will observe the appearance of the Moon from the Earth during the 1st Quarter, or at Position 2. Students will answer the question:

How does the Moon appear at Position 2?

Trial 4

During this trial, students will model the Sun’s illumination of the Moon during Full Moon, or at Position 3. Students will answer the question:

How does the Moon appear at Position 3?

Trial 5

During this trial, students will model the Sun’s illumination of the Moon during the 3rd Quarter, or at Position 4. Students will answer the question:

How does the Moon appear at Position 4?

7. Make sure that students have shaded the circles in each trial to represent the Moon’s appearance.

8. Permit students to finish cleaning the lab and returning materials and equipment to their assigned locations.

KEYS

CLEAN UP

Let students know your expectations for clean-up. Ask them to clean up.