An imaginary line that passes through Earth's center and the North and South poles, about which Earth rotates

The spinning motion of a planet on its axis

The movement of an object around another object

The path of an object as it revolves around another object in space

Either of the two times of the year when the sun is at its greatest distance from the celestial equator

Either of the two days of the year on which neither hemisphere is tilted toward or away from the sun.

The attractive force between objects; the force that moves objects downhill.

the scientific law that states that every object in the universe attracts every other object

The tendency of an object to resist a change in motion