Creep stability of the proposed AIDA mission target 65803 Didymos: I. Discrete cohesionless granular physics model
Creep stability of the proposed AIDA mission target 65803 Didymos: I. Discrete cohesionless granular physics model
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拟议 AIDA 任务目标 65803 Didymos 的蠕变稳定性：I. 离散无粘聚颗粒物理模型
DOI：
10.1016/j.icarus.2017.04.027
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发表时间：
2017-03
期刊：
影响因子：
3.2
通讯作者：
Li Junfeng
中科院分区：
文献类型：
--
作者：
Zhang Yun;Richardson Derek C;Barnouin Olivier S;Maurel Clara;Michel Patrick;Schwartz Stephen R;Ballouz Ronald Louis;Benner Lance A M;Naidu Shantanu P;Li Junfeng
作为拟议的小行星撞击和偏转评估（AIDA）使命的目标，近地双星小行星65803 Didymos是一类特殊的双星小行星，其主星有旋转破裂的危险。为了更好地了解这些二元系统，并支持AIDA的使命，本文研究了蠕变稳定性的Didymos主要代表它作为一个无粘性的自引力颗粒状骨料受到旋转加速度。为了实现这一目标，软球离散元模型（SSDEM）能够模拟颗粒系统在准静态状态的实施和准静态自旋的程序进行。我们设计了三个临界自旋极限的模拟聚集体，以表明其临界状态所触发的重塑和表面脱落，内部结构变形，剪切破坏，分别。骨料的破坏条件、破坏模式和抗剪强度都可以从三个临界旋转极限中推断出来。组成颗粒的排列和尺寸分布，堆积密度，自旋路径，和颗粒间摩擦的影响进行了数值研究。结果表明，自旋自重力骨料的抗剪强度与其内部结构和材料参数密切相关，其破坏模式和破坏机理主要受其内部结构的影响。此外，这项研究提供了一些限制的Didymos主要的观测数据的基础上可能的物理性质，并提出了一个合理的形成机制，这个二元系统。由于体积密度符合观测的不确定性，接近小行星允许的最大密度，Didymos primary在某些配置中可以保持地球静力学稳定，而不需要凝聚力。
As the target of the proposed Asteroid Impact & Deflection Assessment (AIDA) mission, the near-Earth binary asteroid 65803 Didymos represents a special class of binary asteroids, those whose primaries are at risk of rotational disruption. To gain a better understanding of these binary systems and to support the AIDA mission, this paper investigates the creep stability of the Didymos primary by representing it as a cohesionless self-gravitating granular aggregate subject to rotational acceleration. To achieve this goal, a soft-sphere discrete element model (SSDEM) capable of simulating granular systems in quasi-static states is implemented and a quasi-static spin-up procedure is carried out. We devise three critical spin limits for the simulated aggregates to indicate their critical states triggered by reshaping and surface shedding, internal structural deformation, and shear failure, respectively. The failure condition and mode, and shear strength of an aggregate can all be inferred from the three critical spin limits. The effects of arrangement and size distribution of constituent particles, bulk density, spin-up path, and interparticle friction are numerically explored. The results show that the shear strength of a spinning self-gravitating aggregate depends strongly on both its internal configuration and material parameters, while its failure mode and mechanism are mainly affected by its internal configuration. Additionally, this study provides some constraints on the possible physical properties of the Didymos primary based on observational data and proposes a plausible formation mechanism for this binary system. With a bulk density consistent with observational uncertainty and close to the maximum density allowed for the asteroid, the Didymos primary in certain configurations can remain geo-statically stable without requiring cohesion.
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影响因子：
64.8
作者：
P. Pravec;D. Vokrouhlický;D. Polishook;D. Scheeres;A. Harris;A. Galád;Ovidiu Vaduvescu;F. Pozo Nuñez;A. Barr;P. Longa;F. Vachier;F. Colas;D. Pray;J. Pollock;D. Reichart;K. Ivarsen;J. Haislip;A. Lacluyze;P. Kušnirák;T. Henych;F. Marchis;B. Macomber;Seth Andrew Jacobson;Y. Krugly;A. V. Sergeev;A. Leroy
通讯作者：
P. Pravec;D. Vokrouhlický;D. Polishook;D. Scheeres;A. Harris;A. Galád;Ovidiu Vaduvescu;F. Pozo Nuñez;A. Barr;P. Longa;F. Vachier;F. Colas;D. Pray;J. Pollock;D. Reichart;K. Ivarsen;J. Haislip;A. Lacluyze;P. Kušnirák;T. Henych;F. Marchis;B. Macomber;Seth Andrew Jacobson;Y. Krugly;A. V. Sergeev;A. Leroy
影响因子：
3.2
作者：
P. Pravec;A. Harris
通讯作者：
P. Pravec;A. Harris
DOI：
10.1016/j.ijsolstr.2004.05.048
发表时间：
2004-10-01
影响因子：
3.6
作者：
Luding, S
通讯作者：
Luding, S
影响因子：
3.2
作者：
V. Perera;A. Jackson;E. Asphaug;R. Ballouz
通讯作者：
V. Perera;A. Jackson;E. Asphaug;R. Ballouz
DOI：
10.1016/s0020-7225(99)00132-9
发表时间：
2000-10-01
影响因子：
6.6
作者：
Oda, M;Iwashita, K
通讯作者：
Iwashita, K