Different arrival times of CM and CI-like bodies from the outer Solar System to the asteroid belt

Abstract

Understanding the provenance of CI and CM chondrites, the most primitive materials in our meteorite collections, is critical for shedding light on the Solar System's early evolution and contextualizing findings from recent sample return missions. Here we show that the parent bodies of CM chondrites originate from the Saturn formation region, whereas those of CI chondrites originate essentially from the primordial trans-Uranian disk. Using Nbody simulations to investigate the effect of giant planet growth and inward Type-I migration, along with the current observed distribution of CM, CI, and comet-like P types bodies in the asteroid belt, we demonstrate that CI- and CM-like bodies must have been implanted at different times in the belt. In contrast, CI and comet-like bodies were implanted at the same time. These different implantation periods are imposed by the fact that the gas disk profile entirely governs the radial distribution of bodies implanted by aerodynamic drag in the asteroid belt. A preferred location coincides with the inner edge of a gap opened by Jupiter. Saturn's growth likely drove the migration of CM-like bodies. In contrast, CI and comet-like bodies were transported at a later stage during the outward migration of Uranus and Neptune, driven by remaining planetesimals. Since CM chondrites are chondrule-rich, it follows that chondrule formation occurred mostly inward of the ice giants formation zone (under 10 au). A byproduct of our simulations is that only CM-like, not CI-like, bodies contributed to the water budget of the telluric planets.

References in corpus (11)

• Origin of the Structure of the Kuiper Belt during a Dynamical Instability in the Orbits of Uranus and Neptune
• Separating gas-giant and ice-giant planets by halting pebble accretion
• Origin of water in the inner Solar System: Planetesimals scattered inward during Jupiter and Saturn's rapid gas accretion
• Planetesimal rings as the cause of the Solar System's planetary architecture
• The Formation of the Oort Cloud in Open Cluster Environments
• Constraining the giant planets' initial configuration from their evolution: implications for the timing of the planetary instability
• Connecting Asteroids and Meteorites with visible and near-infrared spectroscopy
• Runaway gas accretion and gap opening versus type~I migration
• Pebble accretion at the origin of water in Europa
• Evolution of the reservoirs of volatiles in the protosolar nebula
• On the interaction of pebble accreting embryos with the gaseous disc: importance of thermal forces