Re: Why do geosynch orbits at inclinations > 0 have figure 8 ground tracks ?

Dear John,
As you know, orbiting objects trace an elliptical path around the Earth. According to Kepler's Second Law of motion, planets (and any other orbiting object) sweep out equal areas in the orbital plane in equal periods of time.

All geosynchronous orbits must, by definition, be at 0 degree inclination, that is directly above the equator. It is very difficult to get an orbiting object into a perfectly circular orbit. Any deviation from a perfect circle will cause a speedup and slowdown in angular rotation around the Earth. Additionally, it is very difficult to get a satellite into an orbit that exactly tracks above the equator all the way in its orbit. It will most likely be north of the quator for half of its orbit and south of the equator for the other half. It will cross the equator twice during each orbit. The average will be a geostationary position but not perfectly. The resulting projection of the satellite on the surface of the Earth will trace out a figure 8 as the net effect of all orbital imperfections.

I hope this helps.