Unit 4 (Earth-Sun-Moon)

3. a division of the year that is determined by Earth's tilt relative to the sun and Earth's position in its orbit around the sun
6. the difference in water level between a high tide and a low tide
7. term used to describe Earth's 24-hour rotationary period
9. term used to describe a moon phase that is getting larger (i.e., more lit)
11. the longest or shortest night of the year; occurs on approximately June 21 and December 21
12. day with an equal twelve hours each of light and darkness; occurs on approximately March 21 and September 21
16. shape of the moon where we see the majority of it lit
17. the very darkest part of the moon's shadow
19. a force of attraction between objects that is due to their masses; what keeps the Sun, Earth, and Moon connected to each other
20. the path of an object as it revolves around another object in space
22. The movement of an object around another object
23. the state of the tide when at its highest level.
24. term used to describe a moon phase that is getting smaller (i.e., less lit)
28. less-variable tide that occurs when the Sun and Moon pull at right angles
29. occurs when the Earth casts a shadow on the Moon

1. moon phase that occurs when the Moon cannot be seen because its lighted half is facing the Sun and its dark side faces Earth.
2. the state of the tide when at its lowest level.
4. occurs when the Moon casts a shadow on the Earth
5. moon phase in which the moon is getting bigger and the right half of the Moon can be seen
8. an imaginary line that passes through Earth's center and the North and South poles, about which Earth rotates
10. cyclical rise and fall of water caused by the pull of the Sun and Moon
13. the spinning motion of an object on its axis
14. highly-variable tide that occurs when the Sun and Moon pull in the same direction
15. moon phase in which the moon is getting smaller and the left half of the Moon can be seen
18. cyclical variation in the appearance of the Moon based on its location in reference to the Earth and Sun
21. shape of the moon where we see just a little of it lit
25. moon phase when the entire side facing Earth is illuminated, and the dark side faces away from Earth
26. the lighter part of a shadow where light is partially blocked
27. term used to describe Earth's 365-day revolutionary period