EARTH IN THE UNIVERSE

Orbit To orbit is to move around something

in a circle.

Axis  real or imaginary line on which

something rotates.

Rotation The act or process of turning around

a center or an axis. A complete cycle of circular motion.

Moon Earth’s natural satellite that orbits

the Earth approximately every 28 days, and is visible because it reflects sunlight.

Cycle Repeating sequence.

Revolve To turn around a center point.

Appearance

Act of coming in to view.

Phase Angle that a viewer from earth can

see the moon.

New Moon The moon is between the sun and

earth, so the side facing earth is not illuminated. (The moon is not seen)

First Quarter The right half of the moon is

illuminated.

Full Moon The entire side of the moon facing

the Earth is illuminated.

Last/Third Quarter The left half of the moon is

illuminated.