The dynamics of Neptune Trojans – II. Eccentric orbits and observed objects
The dynamics of Neptune Trojans – II. Eccentric orbits and observed objects
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DOI：
10.1111/j.1365-2966.2010.17566.x
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发表时间：
2010-07
影响因子：
4.8
通讯作者：
Li-Yong Zhou;R. Dvorak;Yi-Sui Sun Department of Astronomy;N. University;Institute for Astronomy;V. University
中科院分区：
文献类型：
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作者：
Li-Yong Zhou;R. Dvorak;Yi-Sui Sun Department of Astronomy;N. University;Institute for Astronomy;V. University
在以前的论文中，我们提出了一个全球性的观点的稳定性海王星特洛伊（NTs以下）的倾斜轨道。作为研究的继续，本文讨论了NT轨道的稳定性对偏心率的依赖性。对于这项任务，高分辨率的动力学地图构建使用的结果广泛的数值积分的初始化的初始半长轴（a 0）与偏心率（e 0）的精细网格上的轨道。在不同倾角的（a 0，e 0）平面上的稳定轨道的区域的扩展。在低倾角（0°，12°）、中倾角（22°，36°）和高倾角（51°，59°）三个最稳定区域，稳定轨道的最大偏心率分别为0.10、0.12和0.04。描述了动力学映射中的精细结构。通过频率分析方法，揭示了描绘动力学地图的机制。在振动共振角λ - λ 8的频率和海王星与天王星之间的准2：1平均运动共振（MMR）的频率处，发现次级共振深深地参与了NT的运动。检测到的长期共振，它们也有助于显着触发的运动中的混沌。特别地，阐明了长期共振ν 8、ν 18的影响。我们还调查了六个观察到的NT的轨道稳定性，通过检查观测误差条内产生的数百个克隆的轨道。我们的结论是，其中四个是深入的稳定区域内，2001年QR 322和2005年T074是例外。2001年QR 322是在最显着的二次共振附近。2005 T074位于稳定轨道与不稳定轨道的分界线附近，可能受到长期共振的影响。
In a previous paper, we presented a global view of the stability of Neptune Trojans (NTs hereafter) on inclined orbits. As the continuation of the investigation, we discuss in this paper the dependence of the stability of NT orbits on the eccentricity. For this task, high-resolution dynamical maps are constructed using the results of extensive numerical integrations of orbits initialized on fine grids of initial semimajor axis (a 0 ) versus eccentricity (e 0 ). The extensions of regions of stable orbits on the (a 0 , e 0 ) plane at different inclinations are shown. The maximum eccentricities of stable orbits in the three most stable regions at low (0°, 12°), medium (22°, 36°) and high (51°, 59°) inclination are found to be 0.10, 0.12 and 0.04, respectively. The fine structures in the dynamical maps are described. Via the frequency-analysis method, the mechanisms that portray the dynamical maps are revealed. The secondary resonances, at the frequency of the librating resonant angle λ - λ 8 and the frequency of the quasi 2:1 mean-motion resonance (MMR hereafter) between Neptune and Uranus, are found to be deeply involved in the motion of NTs. Secular resonances are detected and they also contribute significantly to the triggering of chaos in the motion. In particular, the effects of the secular resonance ν 8 , ν 18 are clarified. We also investigate the orbital stabilities of six observed NTs by checking the orbits of hundreds of clones generated within the observing error bars. We conclude that four of them are deeply inside the stable region, with 2001 QR322 and 2005 T074 being the exceptions. 2001 QR322 is in the close vicinity of the most significant secondary resonance. 2005 T074 is located close to the boundary separating stable orbits from unstable ones, and it may be influenced by a secular resonance.