Topic 3 Lesson 2: Earth’s Movement Vocabulary

 law of universal gravitation

States that every object in the universe attracts every other object

gravity

The attractive force between objects that pulls objects down

inertia

An object to resist a change in motion

axis

An imaginary line that passes through the earths center on which it spins

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

solstice

Two days of the year when the sun reaches its greatest distance north and south

equinox

Two day of the year when neither hemisphere is  tilted towards or away from the sun