Effects of pebble accretion on the growth and composition of planetesimals in the inner Solar system

Author(s): J. Mah, R. Brasser, A. Bouvier, S. J. Mojzsis
Abstract: Recent work has shown that aside from the classical view of collisions by increasingly massive planetesimals, the accretion of mm to m-sized 'pebbles' can also reproduce the mass-orbit distribution of the terrestrial planets. Here, we perform N-body simulations to study the effects of pebble accretion on to growing planetesimals of different diameters located in the inner Solar system. The simulations are run to occur during the lifetime of the gas disc while also simultaneously taking Jupiter's growth into account. We find that pebble accretion can increase the mass in the solid disc by at least a few times its initial mass with reasonable assumptions that pebbles fragment to smaller sized grains at the snow line and that gas-disc-induced orbital migration effects are in force. Such a large contribution in mass by pebbles would seem to imply that the isotopic composition of the inner Solar system should be similar to the pebble source (i.e. outer Solar system). This implication appears to violate the observed nucleosynthetic isotopic dichotomy of the sampled Solar system. Thus, pebble accretion played little or no role in terrestrial planet formation.
Organisation(s): Department of Lithospheric Research
External organisation(s): Max-Planck-Institut für Astronomie, Tokyo Institute of Technology (TIT), Hungarian Academy of Sciences, Universität Bayreuth, University of Colorado, Boulder
Journal: Monthly Notices of the Royal Astronomical Society
Volume: 511
Pages: 158-175
No. of pages: 18
ISSN: 0035-8711
DOI: https://doi.org/10.1093/mnras/stab3766
Publication date: 03-2022
Peer reviewed: Yes
Austrian Fields of Science 2012: 105101 General geology
Keywords
ASJC Scopus subject areas: Astronomy and Astrophysics, Space and Planetary Science
Portal url: https://ucrisportal.univie.ac.at/en/publications/dc00888a-563d-4915-9446-871b42e036ed

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