Dynamical orbital evolution of asteroids and planetesimals across
distinct chemical reservoirs due to accretion growth of planets in the early
solar system
N-body numerical simulations code for the orbital motion of
asteroids/planetesimals within the asteroid belt under the gravitational
influence of the sun and the accreting planets has been developed. The aim is
to make qualitative, and to an extent a semi-quantitative argument, regarding
the possible extent of radial mixing and homogenization of planetesimal
reservoirs of the two observed distinct spectral types , viz., the S-type and
C-type, across the heliocentric distances due to their dynamical orbital
evolution, thereby, eventually leading to the possible accretion of asteroids
having chemically diverse constituents. The spectral S-type and C-type
asteroids are broadly considered as the parent bodies of the two observed major
meteoritic dichotomy classes, namely, the non-carbonaceous (NC) and
carbonaceous (CC) meteorites, respectively. The present analysis is performed
to understand the evolution of the observed dichotomy and its implications due
to the nebula and early planetary processes during the initial 10 Myrs (Million
years). The homogenization across the two classes is studied in context to the
accretion timescales of the planetesimals with respect to the half-life of the
potent planetary heat source, 26Al. The accretion over a timescale of ~1.5 Myr.
possibly resulted in the planetary-scale differentiation of planetesimals to
produce CC and NC achondrites and iron meteorite parent bodies, whereas, the
prolonged accretion over a timescale of 2-5 Myrs. resulted in the formation of
CC and NC chondrites. Our simulation results indicate a significant role of the
initial eccentricities and the masses of the accreting giant planets,
specifically, Jupiter and Saturn, in triggering the eccentricity churning of
the planetesimals across the radial distances......Comment: Accepte