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AN ANALYTIC PARAMETERIZATION OF SELF-GRAVITY WAKES IN SATURN’S RINGS, WITH APPLICATION TO OCCULTATIONS AND PROPELLERS
planets and satellites individual (Saturn)–planets and satellites rings
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2015/12/25
We have developed a semianalytic method of parameterizing N-body simulations of self-gravity wakes in Saturn’s rings, describing their photometric properties by means of only six numbers: three optica...
RUBBLE-PILE RESHAPING REPRODUCES OVERALL ASTEROID SHAPES
methods N-body simulations–minor planets asteroids–planets satellites formation–gravitation
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2015/12/25
There have been attempts in the past to fit the observed bulk shapes (axial ratios) of asteroids to theoretical equilibrium figures for fluids, but these attempts have not been successful in many case...
Planetesimals to protoplanets–II. Effect of debris on terrestrial planet formation
methods N-body simulations–methods numerical–Solar system formation–planetary systems formation
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2015/12/25
In this paper, we extend our numerical method for simulating terrestrial planet formation to include dynamical friction from the unresolved debris component. In the previous work, we implemented a rub...
Asteroid rotation and shapes from numerical simulations of gravitational re-accumulation
Asteroids Asteroid formation Asteroid evolution Collisions
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2015/12/25
We present simulations of the gravitational collapse of a mono-disperse set of spherical particles for studying shape and spin properties of re-accumulated members of asteroid families. Previous numer...
Numerical simulations of asteroids modelled as gravitational aggregates with cohesion
Asteroid structure Asteroid dynamics Asteroid satellites Collisional physics Impact processes
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2015/12/25
Evidence is mounting that asteroids larger than a few hundred metres in diameter are gravitational aggregates of smaller, cohesive pieces. For example, images of 25143 Itokawa show aboulder-strewn sur...
A steady-state model of NEA binaries formed by tidal disruption of gravitational aggregates
Asteroids dynamics Satellites of asteroids
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2015/12/25
We present results of a simulation of a steady-state binary near-Earth asteroid (NEA) population. This study combines previous work on tidal disruption of gravitational aggregates [Walsh, K.J., Richar...
N-Body simulations of growth from 1 km planetesimals at 0.4 AU
Origin, Solar system Planetesimals Planetary formation Earth
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2015/12/25
We present N-body simulations of planetary accretion beginning with 1 km radius planetesimals in orbit about a 1 M star at 0.4 AU. The initial disk of planetesimals contains too many bodies for any c...
Formes d’asteroides et formation de satellites:role de la reaccumulation gravitationnelle
Solar System Asteroids Satellites Collisions
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2015/12/25
Asteroid shapes and satellite formation: role of gravitational re-accumulation.Following current evidence, it is widely accepted that many asteroids would be ‘gravitational aggregates’, i.e. bodies la...
Crater clusters on Mars:Shedding light on martian ejecta launch conditions
Cratering Mars Meteorites Impact processes
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2015/12/25
We have identified two classes of crater clusters on Mars. One class is “small clusters” (crater diameter D ～ tens m, spread over few hundred m), fitting our earlier calculations for the breakup of we...
Size–frequency distributions of fragments from SPH/N-body simulations of asteroid impacts: Comparison with observed asteroid families
Asteroids Collisional physics Impact processes
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2015/12/25
We investigate the morphology of size–frequency distributions (SFDs) resulting from impacts into 100-km-diameter parent asteroids, represented by a suite of 161 SPH/N-body simulations conducted to stu...
Insights into collisional physics may be obtained by studying the asteroid belt, where large-scale collisions produced groups of asteroid fragments with similar orbits and spectra known as the asteroi...
Binary near-Earth asteroid formation:Rubble pile model of tidal disruptions
Asteroids Dynamics Rotational dynamics Tides solid body
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2015/12/25
We present numerical simulations of near-Earth asteroid (NEA) tidal disruption resulting in bound, mutually orbiting systems. Using a rubble pile model we have constrained the relative likelihoods for...
A fast method for finding bound systems in numerical simulations:Results from the formation of asteroid binaries
Asteroids Dynamics Data analysis techniques
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2015/12/25
We present a new code (companion) that identifies bound systems of particles in O(N logN) time. Simple binaries consisting of pairs of mutually bound particles and complex hierarchies consistingof col...
PLANETESIMALS IN THE PRESENCE OF GIANT PLANET MIGRATION
Accretion accretion disks methods:n-body simulations planetary systems planets and satellites general
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2015/12/25
We present N-body simulations illustrating how giant planet migration can significantly affect the conditions for the formation of interior terrestrial planets. A giant planet migrating through aswarm...
PLANETESIMALS TO PROTOPLANETS. I. EFFECT OF FRAGMENTATION ON TERRESTRIAL PLANET FORMATION
n-body simulations planetary systems solar system
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2015/12/25
We present results from a dozen direct N-body simulations of terrestrial planet formation with various initial conditions. In order to increase the realism of our simulations and investigate theeffect...