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Spin-up of rubble-pile asteroids:Disruption,satellite formation,and equilibrium shapes
Asteroid, Dynamics Rotational dynamics Satellites,Dynamics
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2015/12/25
We present results from numerical experiments testing the behavior of cohesionless gravitational aggregates experiencing a gradual increase of angular momentum. The test bodies used in these numerical...
N-body simulations of cohesion in dense planetary rings:A study of cohesion parameters
Planetary rings Saturn, Rings Tides, Solid body Ices, Mechanical properties Collisional physics
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2015/12/25
We present results from a large suite of simulations of Saturn’s dense A and B rings using a new model of particle sticking in local simulations (Perrine, R.P., Richardson, D.C., Scheeres, D.J. [2011]...
A comparison between rubble-pile and monolithic targets in impact simulations:Application to asteroid satellites and family size distributions
Asteroids Collisional physics Impact processes Satellites, General
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2015/12/25
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 t...
Collisional evolution and reddening of asteroid surfaces–I. The problem of conflicting time-scales and the role of size-dependent effects
meteorites meteors meteoroids–minor planets asteroids: general
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2015/12/25
Space weathering is the generic term used for processes that modify the optical properties of surfaces of atmosphereless rocky bodies under exposure to the space environment. The general agreement abo...
An implementation of the soft-sphere discrete element method in a high-performance parallel gravity tree-code
Bulk solids Solar system DEM Hopper SSDEM
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2015/12/25
We present our implementation of the soft-sphere discrete element method (SSDEM) in the parallel gravitational N-body code pkdgrav, a well-tested simulation package that has been used to provide many ...
A numerical model of cohesion in planetary rings
Planetary rings Saturn, Rings Rotational dynamics Tides, Solid body Ices, Mechanical properties Collisional physics
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2015/12/25
We present a numerical method that incorporates particle sticking in simulations using the N-body code pkdgrav to study motions in a local rotating frame, such as a patch of a planetary ring. Particle...
Rotational fission of trans-Neptunian objects:the case of Haumea
Kuiper belt general – Kuiper belt objects individual Haumea – minor planets, asteroids general
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2015/12/25
We present several lines of evidence, based on different kinds of observations, and we conclude that it is likely that rotational fission has occurred for a fraction of the known trans-Neptunian objec...
Numerical simulations of granular dynamics:I. Hard-sphere discrete element method and tests
Asteroids, Surfaces Collisional physics Geological processes Regoliths
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2015/12/25
We present a new particle-based (discrete element) numerical method for the simulation of granular dynamics, with application to motions of particles on small solar system body and planetary surfaces....
Asteroids are leftover pieces from the era of planet formation that help us understand conditions in the early Solar System. Unlike larger planetary bodies that were subject to global thermalmodificat...
The Asteroid Veritas:An intruder in a family named after it?
Asteroids Asteroids, Composition Collisional physics Impact processes
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2015/12/25
The Veritas family is located in the outer main belt and is named after its apparent largest constituent, Asteroid (490) Veritas. The family age has been estimated by two independent studies to be qui...
Asteroids:equilibrium shapes of rotating gravitational aggregates
Asteroids shapes–Numerical simulations–Solar System evolution
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2015/12/25
Many evidences lead us to think that a significant portion of asteroids are aggregates of boulders kept together by gravity, with little or no contribution from cohesive forces. The standard hydrodyna...
Experimental determination of the coefficient of restitution for meter-scale granite spheres
Asteroids Collisional physics Experimental techniques Planetary formation Planetary rings
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2015/12/25
We present results of a series of large-scale experiments to measure the coefficient of restitution for 1-m-diameter rocky bodies in impacts with collision speeds up to 1.5 m s1. The experiments wer...
FORMATION OF KUIPER BELT BINARIES BY GRAVITATIONAL COLLAPSE
Kuiper Belt general – planets and satellites formation – protoplanetary disks
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2015/12/25
A large fraction of {approx}100 km class low-inclination objects in the classical Kuiper Belt (KB) are binaries with comparable masses and a wide separation of components. A favored model for their fo...
Fragment properties at the catastrophic disruption threshold:The effect of the parent body’s internal structure
Asteroids Collisional physics Asteroids, Composition
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2015/12/25
Numerical simulations of asteroid breakups, including both the fragmentation of the parent body and the gravitational interactions between the fragments, have allowed us to reproduce successfully the ...
Hill’s equations are an approximation that is useful in a number of areas of astrophysics including planetary rings and planetesimal disks. We derive a symplectic method for integrating Hill’sequation...