Moon Phase

Real World Example

Imagine trying to read a book while someone keeps turning the dimmer switch on the lights, changing how much of the room and book you can see. This is similar to how the moon's phases change, as the amount of the moon we see illuminated from Earth shifts depending on its position relative to the Earth and the Sun. Just like the dimmer switch controls the light in the room, the moon's position in its orbit controls how much of the sunlit side of the moon is visible from Earth, creating the waxing and waning phases we observe.