Analemma
A Model based on the ideas of Eudoxos of Knidos to simulate the Analemma, the apparent Motion of the sun when taking the position on the celestial sphere once a day at the same daytime for 365 days.
The Figure of Eight is the Analemma for an Earth orbiting the sun on a perfect circle. The shape of the Analemma is modified due to the elliptcal nature of the orbit