Planets do not travel in circles; they follow an ellipse. An ellipse has two foci. When the foci are separated, the ellipse is elongated. If the two foci are superimposed, then the ellipse is a circle. When the foci are separated, the distance between the two foci is measured by the concept of eccentricity. This composition reflects the varying ellipses, i.e. the varying eccentricities.

Performed at Tufts University 10/22/24