1. Chapter 1: Earth, Moon, & Sun
Phases, & Eclipses
Chapter 1: Earth, Moon, & Sun 4

2. Motions of the Moon

3. Why is the “day” on the moon the same length as a “year” on the moon?
Rotation : Day :: Revolution : year
Since it takes 27.3 Earth days for the moon to rotate (day) and 27.3 Earth days for the moon to revolve (year), the day and a year are the same length

4. Checkpoint: How many days does it take the moon to revolve once around Earth?
It takes the moon 27.3 Earth days to revolve around Earth.
It also takes the moon 27.3 Earth days to rotate

5. Phases of the Moon

6. The different shapes of the moon you see from Earth are called _____.
phases

7. The moon goes through its whole set of phases each time it _____ around Earth, or about once a _____.
revolves
month

8. What causes the phases of the moon?
The phases of the moon are caused by the change of the relative positions of Earth, the moon, and sun.
Since the moon revolves around Earth we see it from different angles
The ½ of the moon that faces Earth is not always the ½ lit up by the sun causing the moon’s shape to appear to change
The phase of the moon you see depends on how much of the sunlit side of the moon faces Earth

10. What is the length of time from a new moon to the next new moon?
29.5 Earth days
Since Earth is revolving it takes an extra 2.2 Earth days for the sun, moon and Earth to line up, causing the next new moon

11. Checkpoint: Since the moon does not produce light, how can you see it?
Light from the sun reflects off the moon, enabling it to be seen from Earth.

12. Eclipses

13. Figure 6: Interpreting Diagrams How large is the angle between Earth’s orbit and the moon’ s orbit?
The angle between Earth’s orbit and the of the moon is 5º

14. When does an eclipse occur?
In a rare occasion when the moon or Earth becomes directly between the sun and the other and cast a shadow on that object

15. The two types of eclipses are ______ & ______.
lunar
solar

16. Solar Eclipses

17. Solar Eclipse
A solar eclipse occurs when the moon comes directly between the sun and Earth
The moon blocks Earth from sunlight and cast a shadow
Earth’s sky becomes darker and you can only see the corona of the sun

19. At what phase of the moon could a solar eclipse occur?
A new moon when the moon becomes directly between the sun and Earth

20. The darkest part of the moon’s shadow is called the _________.
Umbra

21. Why are the people in the umbra the only ones that experience a total solar eclipse?
The umbra is the darkest part of the of the moon’s shadow
People who are in the umbra are in the darkest part of the shadow where the moon is almost completely blocking sunlight from reaching Earth, except for the sun’s corona.

22. Penumbra
The larger less dark shadow cast by the moon during a solar eclipse and by Earth during a lunar eclipse

23. Lunar Eclipses

24. What is a lunar eclipse?
A lunar eclipse occurs when Earth comes directly between the sun and moon
Earth blocks the moon from sunlight and cast a shadow
The moon turns a red/orange color

26. Figure 8: Interpreting Diagrams: What is the difference between Earth’s umbra and penumbra?
The umbra is in the area of total darkness, the penumbra is the area of partial darkness

27. Checkpoint: Why do lunar eclipses occur only at full moon?
Earth must come between the sun and the moon during a lunar eclipse; this only happens during the full moon phase.

28. What causes solar and lunar eclipses?
When the moon’s shadow hits Earth or Earth’s shadow hits the moon, an eclipse occurs.
Eclipses occur when the moon’s orbit which is usually tilted becomes not tilted and the sun, moon and Earth line up perfectly