Re: strictly speaking
Hmmm... Not a lot of moving mass on Mars (oceans), specifically mass that is moving around in a lossy fashion due to those flea size moons. So seems a bit dubious.
You don't need liquid to perturb orbits. Earth's equatorial spare tire and Luna's masscons do a fine job of nudging orbits.
Apollo 16's subsatellite PFS-2 was placed in an almost perfectly incorrect orbit that exposed it heavily to lunar surface mass anomalies. Within 2.5 weeks of release, its elliptical 89x122 km orbit had varied to within 9.7km of the lunar surface. It seemed to back off to 50km, but after just 35 days it performed an unscheduled lithobraking maneuver. Later, it was found that Luna had four "frozen" orbits much less influenced by lunar gravitational anomalies.
Mars is a fairly lumpy world, with differences between northern and southern hemispheres that should make long-term predictions of MAVEN's orbit interesting.
Biting the hand that feeds IT
