I used a loop for the stars and comet, and conditionals to change the phases of the moon. I tracked the position of the ellipse to coordinate the phases of the moon, by giving it it's own integer (xPos).
I made ellipses within the loop to make a trail.

The cat represents the peoples need to be greedy and consume everything materialistic. The points counter represents society's respect and encouragement of materialistic values. The point of this demonstration is that you must catch the balls to get points. Multicolored balls represent the trends and fads, they change colors to look pretty but really are the same things thrown at society being recycled. There is no endpoint, showing this cycle never ends.

Documentation of process:
I drew an image of a cat, and wanted to control its position with a sensor. I experimented with light and tilt sensors, but found them to be too sensitive for my purpose. So, to make a more steady, controllable movement, I used the potentiometer.