Earth-Sun-Moon System

4. Day with an equal twelve hours each of light and darkness; occurs on approximately March 21 and September 21
6. Cyclical rise and fall of water caused by the pull of the Sun and Moon
7. a force of attraction between objects that is due to their masses; what keeps the Sun, Earth, and Moon connected to each other
11. the very darkest part of the moon's shadow
13. moon phase in which the moon is getting bigger and the right half of the Moon can be seen
16. the path of an object as it revolves around another object in space
18. moon phase that occurs when the Moon cannot be seen because its lighted half is facing the Sun and its dark side faces Earth.
19. the lighter part of a shadow where light is partially blocked
20. moon moon phase when the entire side facing Earth is illuminated, and the dark side faces away from Earth
21. The longest or shortest night of the year; occurs on approximately June 21 and December 21
23. 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
25. the state of the tide when at its highest level.
27. the difference in water level between a high tide and a low tide
28. an imaginary line that passes through Earth's center and the North and South poles, about which Earth rotates
29. Shape of the moon where we see just a little of it lit

1. term used to describe a moon phase that is getting smaller (i.e., less lit)
2. term used to describe a moon phase that is getting larger (i.e., more lit)
3. the state of the tide when at its lowest level.
5. Less-variable tide that occurs when the Sun and Moon pull at right angles
8. moon phase in which the moon is getting smaller and the left half of the Moon can be seen
9. term used to describe Earth's 365-day revolutionary period
10. Shape of the moon where we see the majority of it lit
12. Cyclical variation in the appearance of the Moon based on its location in reference to the Earth and Sun
14. The movement of an object around another object
15. Occurs when the Earth casts a shadow on the Moon
17. Occurs when the Moon casts a shadow on the Earth
22. the spinning motion of an object on its axis
24. Highly-variable tide that occurs when the Sun and Moon pull in the same direction
26. term used to describe Earth's 24-hour rotationary period