 The difference in size of the lobes of the figure-eight form arises mainly from the fact that the perihelion and aphelion occur far from equinoxes.They also occur a mere couple of weeks after solstices, which in turn causes slight tilt of the figure eight and its minor lateral asymmetry.There are three parameters that affect the size and shape of the analemma—obliquity, eccentricity, and the angle between the apse line and the line of solstices.