| A | B |
|---|
| Astronomy | The study of the moon, stars, and other objects in space. |
| Rotation | The spinning motion of a planet on its axis. |
| Revolution | The movement of an object around another object. |
| Orbit | The path of an object as it revolves around another object in space. |
| Lunar Eclipse | The blocking of sunlight to the moon that occurs when Earth is directly between the sun and the moon. |
| Umbra | The darkest part of a shadow. |
| Penumbra | The part of a shadow surrounding the darkest part. |
| Tide | The periodic rise and fall of the level of water in the ocean. |
| Phases | The different shapes of the moon you see from Earth. |
| Solar Eclipse | The blocking of sunlight to Earth that occurs when the moon is directly between the sun and Earth. |
| Weight | The force of gravity on an object. |
| Inertia | The tendency of an object to resist a change in motion. |
| Force | A push or a pull exerted on an object. |
| Mass | The amount of matter in an object. |
| Solstice | The two days of the year on which the sun reaches its greatest distance north or south of the equator. |
| Equinox | The two days of the year on which neither hemisphere is tilted toward or away from the sun. |
| Telescope | A device built to observe distant objects by making them appear closer. |
| Crater | A large round pit caused by the impact of a meteoroid. |
| Meteoroids | Chunks of rock or dust in space. |
| Maria | Dark, flat areas on the moon’s surface formed from huge ancient lava flows. |
