Earth, Moon, Sun System

1. the imaginary line that divides Earth into the Northern and Southern Hemispheres
3. the lighter part of a shadow where light is partially blocked.
5. tide, the largest tidal range that occurs when the Sun, Earth, and the Moon form a straight line.
6. the large, dark, flat areas on the Moon.
8. the lit part of the Moon or a planet that can be seen from Earth.
10. range, the difference in water height between a high tide and a low tide.
11. when Earth's rotation axis is tilted directly toward or away from the Sun.
12. tide, the periodic rise and fall of the ocean’s surface caused by the gravitational force between Earth and the Moon, and Earth and the Sun.
13. eclipse, an occurrence during which the Moon moves into Earth's shadow.
15. phases, phases of the Moon during which more of the Moon’s near side is lit each night.
19. tide, when the ocean's surface reaches its lowest point.
20. tide, the predictable rise and fall of the ocean's surface each day.
21. the orbit of one object around another object.
23. the amount of energy that passes through a square meter of space in one second.

2. the central, darker part of a shadow where light is totally blocked.
4. when Earth's rotation axis is tilted neither toward nor away from the Sun.
7. the spin of an object around its axis.
9. the line around which an object rotates.
12. the path an object follows as it moves around another object.
14. tide, the lowest tidal range that occurs when the Sun, Earth, and the Moon form a right angle.
16. an attractive force that exists between all objects that have mass.
17. eclipse, an occurrence during which the Moon's shadow appears on Earth's surface.
18. phases, phases of the Moon during which less of the Moon’s near side is lit each night.
22. tide, when the ocean's surface reaches its highest point.