Select Page
```2. In each figure below (A–D) the Moon is shown in a particular phase along with the position in the sky that the Moon would have at one time during a day (or night) throughout a month. The dark areas on each moon figure show the unlit portions of the Moon visible from Earth at that time. So the respective phases are: A (3rd Q), B (Full), C (3rd Q), D (1st Q)

Use the approximate time each Moon phase (A–D) would appear as shown to rank the figures from earliest to latest, starting at sunrise. Place the appropriate letter in the blank space.

Ranking Order: Earliest (sunrise) 1 ___ 2 ____ 3 ____ 4 ____ Latest (sunrise the next day)
Carefully explain your reasoning for ranking each figure this way.

Section C. Why doesn’t the Moon rise at the same time every day?
3. Using several sentences and your own drawing, explain why the Moon rises at a later time from night to night.

Extra-credit (10 points): Use arithmetic to show why the Moon rises ~50 minutes later each day.

Section D. Does the Moon rotate?
From Earth, it appears that the same side of the Moon always faces the Earth, no matter where the Moon is in its orbit around Earth. This effect is called "synchronous rotation.”

4. Although a person on Earth always sees the same side of the Moon, what would someone located elsewhere in the Solar System see? Does the Moon rotate from his/her perspective? Explain your reasoning and use your own drawing	to illustrate your words.

5. Can a person on the Moon ever see an "Earth-rise"? Why or why not?

6. All locations on the Moon experience day and night. Based on our model, how long is a day on the Moon?

7. Suppose you could watch the Earth from a First Quarter Moon during a single 24 hour day. Circle any of the following statements that are correct:
a). Earth would seem to go through phases;
b). Earth would always appear to have a Full phase;
c). Earth would always appear to have a Third Quarter phase;
d). Earth would seem to rise and set.

Section E. Do other planets show phases?
Assume that the Sun is located in the center of the Solar System (i.e., a “heliocentric” model) with the planets revolving in orbits around it at different speeds.

8. In several sentences, explain why (a) Venus could never see a "New Earth” and (b) how the Earth could see a “nearly Full Venus.” Use your own diagram to illustrate your thinking.

9. Explain why the “outer” planets like Mars, Jupiter, and Saturn can never be seen in a New phase by people on Earth. Use your own diagram to illustrate your thinking.

```