Studies extending over three decades have concluded that the current orientation of the martian rotation pole is unsta
ble. Specifically, the gravitational figure of the planet, after correction for a hydrostatic form, has
been interpreted to indicate that the rotation pole should move easily
between the present position and a site on the current equator, 90
b0; from the location of the massive Tharsis volcanic province. We demonstrate, using general physical arguments supported
by a fluid Love num
ber analysis, that the so-called non-hydrostatic theory is an inaccurate framework for analyzing the rotational sta
bility of planets, such as Mars, that are characterized
by long-term elastic strength within the lithosphere. In this case, the appropriate correction to the gravitational figure is the equili
brium rotating form achieved when the elastic lithospheric shell (of some thickness
LT) is accounted for. Moreover, the current rotation vector of Mars is shown to
be sta
ble when the correct non-equili
brium theory is adopted using values consistent with recent, independent estimates of
LT. Finally, we compare o
bservational constraints on the figure of Mars with non-equili
brium predictions
based on a large suite of possi
ble Tharsis-driven true polar wander (TPW) scenarios. We conclude, in contrast to recent comparisons of this type
based on a non-hydrostatic theory, that the reorientation of the pole associated with the development of Tharsis was likely less than 15
b0; and that the thickness of the elastic lithosphere at the time of Tharsis formation was at least
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border=""0"">50 km. Larger Tharsis-driven TPW is possi
ble if the present-day gravitational form of the planet at degree 2 has significant contri
butions from non-Tharsis loads; in this case, the most plausi
ble source would
be internal heterogeneities linked to convection.