PERSEID

Meteorites provide key insights on the evolution of the solar system. The recent discovery of a fundamental isotopic dichotomy between non-carbonaceous (NC) and carbonaceous (C) meteorites attests that the solar system was divided by a physical barrier into two distinct reservoirs. However, the nature and permeability of this barrier remain unclear. These uncertainties impact our understanding of how terrestrial planets formed in the inner solar system. Deciphering the permeability of the NC/C barrier can be approached by studying chondrules –submillimeter spheroids representing the most abundant high-temperature material in NC and carbonaceous chondrites (CC). Although this makes chondrules a unique tracer of disk processes, no dedicated study has yet investigated the potential inward migration of CC-like chondrules into the terrestrial planet-forming zone. In this context, a fundamental observation has remained largely overlooked: the size-dependent oxygen isotopic compositions of chondrules in NC chondrites. Chondrules smaller than 300 µm exhibit isotopic compositions that trend toward those of CC chondrules. Determining whether this chondrule population originated from the outer solar system or formed locally in an evolving inner disk is essential for assessing the permeability the NC/C barrier. This question represents the primary objective of the PERSEID project. The PERSEID project will focus on size-variable NC chondrules, examining their petrographic features, bulk chemical compositions, O-Cr-Ti isotopic compositions, and Al-Mg systematics. Specifically, the project will address: (i) multi-scale transport and mixing processes in the solar accretion disk, (ii) the nature and timing of chondrule formation in the NC reservoir, (iii) the isotopic evolution of the NC reservoir and its implications for the permeability and nature of the NC/C barrier. These findings will enhance our understanding of dust transfer in the protoplanetary disk.