| A | B |
|---|
| Geocentric Model | A model that places the Earth at the center of the universe |
| Heliocentric Model | A model that places our Sun at the center of our solar system |
| Rotation | A spinning motion of a celestial body |
| Revolution | The motion of one celestial body around another |
| Orbit | The path a celestial body follows when revolving around another celestial body |
| Period of Rotation | The amount of time it takes to compete one rotation |
| Period of Revolution | The amount of time it takes to complete one revolution |
| Axis | An imaginary line around which a celestial body rotates |
| Coriolis Effect | Causes objects moving large distances on Earth to curve from a straight path |
| Constellation | A group of stars which appear together in the sky |
| Summer Solstice | The day with the most hours of daylight. Around June 21 |
| Winter Solstice | The day with the fewest hours of daylight. Around December 21 |
| Equinoxes | Days with exactly 12 hours of daylight. Around March 21 and September 21. |
| Tides | Changing sea level caused by the Moon's gravitaional attraction |
| Moon Phases | Changing appearance of the reflected light from the Moon |
| Solar Eclipse | The Moon prevents sunlight from reaching parts of the Earth |
| Lunar Eclipse | The Earth prevents sunlight from reaching parts of the Moon |
