The change in Jupiter's moment of inertia due to core erosion and planetary contraction

We explore the change in Jupiter's normalized axial moment of inertia (NMOI) assuming that Jupiter undergoes core erosion. It is found that Jupiter's contraction combined with an erosion of 20 M _⊕ from a primordial core of 30M _⊕ can significantly change Jupiter's NMOI over time. It is shown that Jupiter's NMOI could have changed from 0.235 to 0.264 throughout its evolution. We find that an NMOI value of 0.235 as suggested by dynamical models could, in principle, be consistent with Jupiter's primordial internal structure. Low NMOI values, however, persist only for the first 10⁶years of Jupiter's evolution. Re-evaluation of dynamical stability models as well as more sophisticated evolution models of Jupiter with core erosion seem to be required in order to provide more robust estimates for Jupiter's primordial NMOI.