TY - JOUR
T1 - A comparison between rubble-pile and monolithic targets in impact simulations
T2 - Application to asteroid satellites and family size distributions
AU - Benavidez, Paula G.
AU - Durda, Daniel D.
AU - Enke, Brian L.
AU - Bottke, William F.
AU - Nesvorný, David
AU - Richardson, Derek C.
AU - Asphaug, Erik
AU - Merline, William J.
N1 - Funding Information:
This project is supported by National Science Foundation Grant AST0708517 . This work was done while the first author was spending a stay at SwRI. P.G.B. acknowledges the Generalitat Valenciana (Consellerı´a de Educación) for providing the financial support for this long-term visit and the partially suport by Spanish grant AYA2008-06202-C03-03. D.C.R. acknowledges support by the National Aeronautics and Space Administration under Grant No. NNX08AM39G issued through the Office of Space Science. E.A. thanks the NASA Planetery Geology and Geophysics Program. W.J.M. acknowledges the NASA and NSF Planetary Astronomy Programs. We appreciate the comments from A. Cellino and an anonymous reviewer that helped to improve this manuscript.
PY - 2012/5
Y1 - 2012/5
N2 - Collisions are a fundamental process in the creation of asteroid families and in satellite formation. For this reason, understanding the outcome of impacts is fundamental to the accurate modeling of the formation and evolution of such systems. Smoothed-Particle Hydrodynamics/N-body codes have become the techniques of choice to study large-scale impact outcomes, including both the fragmentation of the parent body and the gravitational interactions between fragments. It is now possible to apply this technique to targets with either monolithic or rubble-pile internal structures. In this paper we apply these numerical techniques to rubble-pile targets, extending previous investigations by Durda et al. (Durda, D.D., Bottke, W.F., Enke, B.L., Merline, W.J., Asphaug, E., Richardson, D.C., Leinhardt, Z.M. [2004]. Icarus 170, 243-257; Durda, D.D., Bottke, W.F., Nesvorný, D., Enke, B.L., Merline, W.J., Asphaug, E., Richardson, D.C. [2007]. Icarus 186, 498-516). The goals are to study asteroid-satellite formation and the morphology of the size-frequency distributions (SFDs) from 175 impact simulations covering a range of collision speeds, impact angles, and impactor sizes. Our results show that low-energy impacts into rubble-pile and monolithic targets produce different features in the resulting SFDs and that these are potentially diagnostic of the initial conditions for the impact and the internal structure of the parent bodies of asteroid families. In contrast, super-catastrophic events (i.e., high-energy impacts with large specific impact energy) result in SFDs that are similar to each other. We also find that rubble-pile targets are less efficient in producing satellites than their monolithic counterparts. However, some features, such as the secondary-to-primary diameter ratio and the relative separation of components in binary systems, are similar for these two different internal structures of parent bodies.
AB - Collisions are a fundamental process in the creation of asteroid families and in satellite formation. For this reason, understanding the outcome of impacts is fundamental to the accurate modeling of the formation and evolution of such systems. Smoothed-Particle Hydrodynamics/N-body codes have become the techniques of choice to study large-scale impact outcomes, including both the fragmentation of the parent body and the gravitational interactions between fragments. It is now possible to apply this technique to targets with either monolithic or rubble-pile internal structures. In this paper we apply these numerical techniques to rubble-pile targets, extending previous investigations by Durda et al. (Durda, D.D., Bottke, W.F., Enke, B.L., Merline, W.J., Asphaug, E., Richardson, D.C., Leinhardt, Z.M. [2004]. Icarus 170, 243-257; Durda, D.D., Bottke, W.F., Nesvorný, D., Enke, B.L., Merline, W.J., Asphaug, E., Richardson, D.C. [2007]. Icarus 186, 498-516). The goals are to study asteroid-satellite formation and the morphology of the size-frequency distributions (SFDs) from 175 impact simulations covering a range of collision speeds, impact angles, and impactor sizes. Our results show that low-energy impacts into rubble-pile and monolithic targets produce different features in the resulting SFDs and that these are potentially diagnostic of the initial conditions for the impact and the internal structure of the parent bodies of asteroid families. In contrast, super-catastrophic events (i.e., high-energy impacts with large specific impact energy) result in SFDs that are similar to each other. We also find that rubble-pile targets are less efficient in producing satellites than their monolithic counterparts. However, some features, such as the secondary-to-primary diameter ratio and the relative separation of components in binary systems, are similar for these two different internal structures of parent bodies.
KW - Asteroids
KW - Collisional physics
KW - Impact processes
KW - Satellites, General
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U2 - 10.1016/j.icarus.2012.01.015
DO - 10.1016/j.icarus.2012.01.015
M3 - Article
AN - SCOPUS:84860254262
SN - 0019-1035
VL - 219
SP - 57
EP - 76
JO - Icarus
JF - Icarus
IS - 1
ER -