The Triaxial Shape and Surface Irregularities of Mars: Geological Processes and the Nerio Hypothesis

Abstract

Mars differs significantly from a perfect sphere and is more accurately described as a triaxial ellipsoid with large-scale surface irregularities. Unlike Earth, whose stronger gravity smooths much of its surface into a more uniform shape, Mars displays substantial topographic variation caused by volcanic activity, crustal thickness differences, ancient impacts, and tectonic processes. These irregularities produce a planetary form often compared to a lumpy or imbalanced rugby ball.

In addition to established geological explanations, some theoretical models propose that Mars may once have possessed an ancient moon, sometimes referred to hypothetically as Nerio, whose gravitational influence and eventual destruction could have contributed to crustal deformation and planetary imbalance. This article examines the physical and geological processes responsible for the shape of Mars, including rotational deformation, volcanic loading, hemispheric asymmetry, and speculative satellite interaction theories.