Moon Lab- Astronomy

Objectives: The purpose of this lab is to get you to understand the phases of the moon and the relationships between the Sun, Earth, and Moon.

I. Night and Day

For the first section of this lab you will be pretending that your head is the Earth (the North Pole will be the top of your head, and the South Pole will be under your chin), and a light bulb will be the Sun.

SETUP: (Yes you really need to do this — but don’t worry, it’s fun, and easy!) You will need a fairly dark room (the darker the better!) with one bright lamp at about head level while you are standing or sitting. A single bright, uncovered light bulb works best.

1.

Stand (or sit) facing the light bulb (Sun). The diagram below illustrates this setup as seen from above your head, so from above the North Pole of the Earth. Which of the lettered locations indicates the position of a person who lives on the end of your nose?

abcdef

2.

Which of the lettered locations indicates the position of a person who lives on your left ear?

A

B

C

D

E

F

Not visible from this vantage point

3.

Let’s say you wanted to shade in the night side of Earth in the above diagram. Which of the numbered diagrams below shows the night side of Earth properly shaded in?

1

2

3

4

5

4.

As seen from above the North Pole, the Earth rotates counter-clockwise. Refer to the lettered locations in the first diagram at the top. Indicate the places on your head where it is the following times of day:

A. a

B. b

C. c

D. d

E. e

noon

sunset

midnight

sunrise

no time — this is the lightbulb, not a location on your head

5.

What time of day would it be for a person that lives on the end of your nose when you are directly facing the light bulb?

12am midnight

3am

6am (sunrise)

9am

12pm noon

3pm

6pm (sunset)

9pm

6.

Turn your body in place a quarter circle to the left (counterclockwise as viewed from the top down), but do not move the lightbulb. Now the light bulb should be off your right ear. Now what time is it for someone who lives on the end of your nose?

12am midnight

3am

6am (sunrise)

9am

12pm

noon

3pm

6pm (sunset)

9pm

7.

Turn your body another quarter turn to the left. Now the light bulb will be directly behind you. Now what time is it for someone who lives on the end of your nose?

12am midnight

3am

6am (sunrise)

9am

12pm

noon

3pm

6pm (sunset)

9pm

8.

Turn your body another quarter turn to the left. Now the light bulb will be off your left ear. Now what time is it for someone who lives on the end of your nose?

12am midnight

3am

6am (sunrise)

9am

12pm

noon

3pm

6pm (sunset)

9pm

II. Moon Phases

Now we are going to examine the phases of the moon. Hold up a small ball to represent the moon at about head level, taking care not to block your view of the side of the ball facing you with your fingers. (Ideally, if you have access to a small styrofoam ball with a small hole in it, place this ball on the tip of an upright pen or pencil, so none of the ball’s surface is blocked.) You will be holding the Moon out at arm’s length and describing its appearance at different points in its orbit. You will turn around in place, keeping the moon at arm’s length, to simulate the orbit of the Moon (the ball) around Earth (you). The light from the lightbulb will simulate sunlight. Stand as far away from the lightbulb as possible, still staying within your otherwise dark room, and make sure you can turn in place all the way around without hitting anything with your outstretched arm.

Below is a diagram, as seen from above your head (above the Earth’s North Pole), of the Moon’s orbit around the Earth. (Note: it is NOT drawn to scale.) In this diagram the Earth rotates (spins) counter-clockwise in place, and the Moon orbits the Earth in a counter-clockwise direction. Each of these motions are shown with arrows. To represent that the sun is very far away, the sunlight is represented as arrows coming in from off the side of the diagram. You will notice eight different numbered positions in the moon’s orbit that we will be examining in this exercise: Each location corresponds with a different “phase” of the moon, as listed immediately below the diagram.