Planetesimal collisions as a chondrule forming event

Abstract

Chondritic meteorites contain unique spherical materials named chondrules: sub-mm sized silicate grains once melted in a high temperature condition in the solar nebula. We numerically explore one of chondrule forming processes, planetesimal collisions. Previous studies found that impact jetting via protoplanet-planetesimal collisions make chondrules with an amount of 1 % of impactors' mass, when impact velocity exceeds 2.5 km s${}^{-1}$. Based on the mineralogical data of chondrules, undifferentiated planetesimals would be more suitable for chondrule-forming collisions than potentially differentiated protoplanets. We examine planetesimal-planetesimal collisions using a shock physics code and find two things: one is that planetesimal-planetesimal collisions produce the nearly same amount of chondrules as protoplanet-planetesimal collisions ($\sim$ 1 %). The other is that the amount of produced chondrules becomes larger as the impact velocity increases when two planetesimals collide with each other. We also find that progenitors of chondrules can be ejected from deeper regions of large targets (planetesimals or protoplanets) than small impactors (planetesimals). The composition of targets is therefore important to fully account for the mineralogical data of currently sampled chondrules.

arXiv comment10 pages, 6 figures, 2 tables, accepted for publication in ApJ

References in corpus (5)

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Cited by in corpus (13)

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• Jetting during oblique impacts of spherical impactors
• Formation of Terrestrial Planets
• Compound chondrule formation in optically thin shock waves
• Chondrules from high-velocity collisions: thermal histories and the agglomeration problem
• Ejection of Chondrules from Fluffy Matrices
• The late formation of chondrites as a consequence of Jupiter-induced gaps and rings
• Igneous Rim Accretion on Chondrules in Low-Velocity Shock Waves
• Chondrule Accretion with a Growing Protoplanet
• Reproduction Experiments of Radial Pyroxene Chondrules Using a Gas-jet Levitation System under Reduced Conditions
• The Properties of Planetesimal Collisions under Jupiter's Perturbation and the Application to Chondrule Formation via Impact Jetting
• Abundances of ordinary chondrites in thermally evolving planetesimals