We’re doing our units in eighths of an inch, and since the largest circle has a diameter of 2 3/8″, or 19/8″, the radius will be 9.5 units. Also add another circle with a radius of 4.

Since the Milky Way is a flat disk, it should appear as a straight line across the sky. However, in photos such as on pages 50–51 of the April issue, it is a curved arc.