For the Phases and Eclipses of the Moon lab, each work table has a four-foot-long optical
bench set up. Each optical bench has a bright extended light source (a lamp holder with a 50-
watt indoor flood lamp) at one end. In the middle of the bench is an Earth/Moon model
consisting of a rotating center shaft with an angled end attached to which is a 2 inch rotatable
Styrofoam 7 ball. Attached to this Earth representation is a wire arm with a smaller Styrofoam 7
ball at its end, representing the moon. The wire arm assembly can revolve around the Earth
model (See Figure 3). In addition, there is provided a metal slide that has a small hole in its
center. This slide can be placed in front of the lamp to simulate a point source of light. There is
also a screen on a shaft which can be used to observe shadows created by the model when
configured according to tutorial instructions.