Isotopic variation of non-carbonaceous meteorites caused by dust leakage across the Jovian gap in the solar nebula.

The article investigates how dust leaking across the gap created by early-formed Jupiter in the solar nebula influences the isotopic dichotomy observed between non-carbonaceous (NC) and carbonaceous (CC) meteorites, focusing on the chromium isotopic anomaly |$\varepsilon^{54}$Cr|. Using a model that simulates dust size evolution with coagulation, fragmentation, radial drift, and turbulent diffusion in a protoplanetary disk with a Jupiter-induced gas gap, the study assumes that NC and CC meteorite parent bodies formed in two dust reservoirs inside and outside Jupiter’s orbit. Results show that while large dust aggregates accumulate at the outer gap edge (CC reservoir), smaller fragments leak inward through turbulent diffusion, contaminating the inner reservoir (NC reservoir) and causing a temporal increase in |$\varepsilon^{54}$Cr| consistent with meteoritic data around 2 Myr after calcium–aluminum-rich inclusion formation. The efficiency of this dust leakage depends on turbulence strength and dust stickiness, with moderate turbulence and fragmentation reproducing observed isotopic trends, whereas weak turbulence or low stickiness suppress or enhance leakage, respectively. The study concludes that early Jupiter formation can sustain spatial isotopic heterogeneity despite dust leakage and that the temporal isotopic variation in NC meteorites can be explained by this leakage, though variations in CC meteorites may require additional dust traps or processes.