| A | B |
|---|
| Axis | imaginary line about which an object rotates |
| Gravitational attraction | force of attraction between all masses in the universe, especially the attraction of the Earth's mass for bodies near its surface |
| Neap tide | occurs at the first and third (last) quarter Moon phases; the Sun is at a right angle to the Moon |
| Rotational axis | an imaginary line in which a three-dimensional object rotates around; the Earth spins on its axis |
| Spring tide | occurs at the full and new Moon phases; Earth, Moon, and Sun are in alignment pulling the water in the same direction |
| Tide | the rising and falling of the oceans due to the gravitational attraction of the Moon and Sun; usually occurs twice each day |
| Length of Moon's Orbit around Earth | 28 days |
| Length of Earth's Orbit around Sun | 365 days |
