论文标题
丘比特尚未注定：关于天王星内月亮的稳定性
Cupid Is Not Doomed Yet: On the Stability of the Inner Moons of Uranus
论文作者
论文摘要
天王星的某些小内月亮具有非常高的轨道。多项数值研究发现，在Portia子组中，Cressida和Desdemona可能会在不到100 MYR的情况下碰撞。随后发现三个新卫星（丘比特，佩迪塔和mab）的发现使该系统变得更加拥挤。特别是，有人建议贝琳达集团（Cupid，Belinda和Perdita）将在短短10美元的5美元中变得不稳定。在这里，我们使用更新的轨道元素和考虑潮汐消散来重新审视天王星内月亮的稳定性问题。我们发现，由于Belinda和Perdita之间的轨道共振，Belinda集团可以在$ 10^8 $ - 年限的时间内保持稳定。我们发现潮汐演化不能形成Belinda-Perdita共鸣，但是融合迁移可能会导致Portia群体的长期不稳定。我们建议贝琳达在内在的卫星中的中断和重新挑战的最后一集中，可能是数百名Myr以前。
Some of the small inner moons of Uranus have very closely-spaced orbits. Multiple numerical studies have found that the moons Cressida and Desdemona, within the Portia sub-group, are likely to collide in less than 100 Myr. The subsequent discovery of three new moons (Cupid, Perdita, and Mab) made the system even more crowded. In particular, it has been suggested that the Belinda group (Cupid, Belinda, and Perdita) will become unstable in as little as 10$^5$ years. Here we revisit the issue of the stability of the inner moons of Uranus using updated orbital elements and considering tidal dissipation. We find that the Belinda group can be stable on $10^8$-year timescales due to an orbital resonance between Belinda and Perdita. We find that tidal evolution cannot form the Belinda-Perdita resonance, but convergent migration could contribute to the long-term instability of the Portia group. We propose that Belinda captured Perdita into the resonance during the last episode of disruption and re-accretion among the inner moons, possibly hundreds of Myr ago.
