Dissipation of the Solar System's debris disk recorded in primitive meteorites

Many newly formed Sun-like stars show evidence of debris disks composed of dust generated through destructive collisions among residual planetesimals. These are inferred to survive at a detectable level over the first similar to 100 Myr of their parent star's lifetime. We hypothesize that the most primitive meteorites were processed as a result of impacts as our Solar System's debris disk dissipated, rather than as a result of heat generated by decay of Al-26. We show how the iodine-xenon (I-Xe) record from chondrules in the Chainpur meteorite supports this hypothesis, and use it to constrain the decline in the impact rate. We demonstrate that it is the creation of I-Xe sites during compaction that is recorded by the chondrule dataset. We show that, to account for the broader I-Xe record from primitive material, a consistent picture requires that the dissipation of our Solar System's debris disk had a timescale of around 40-50 Myr in this period. Against this backdrop, the late addition of siderophiles to the Earth in a single large impact may represent a rare phenomenon in planetary system formation that has been anthropically selected.