论文标题
在极性系统中动态不稳定的月亮的后果
Consequences of dynamically unstable moons in extrasolar systems
论文作者
论文摘要
在其他恒星的紧凑轨道上旋转的岩石外球星的卫星经历了加速的潮汐进化，并且可以与他们的父行星合并，或者在哈勃时间内达到动态不稳定性的极限。 我们回顾了卫星无界的参数空间，包括大气潮对行星旋转的影响。我们发现，尽管在有限的参数空间上，但这种潮流可以将最终结果从合并变为逃脱。我们还遵循未结合月球的进一步演变，并证明绝大多数最有可能的长期结果是未结合的月亮返回与其原始的父行星碰撞。据估计，这种碰撞释放的尘埃估计达到约0.001的光学深度，表现出几百度开尔文的特征温度，并且持续了几千年。这些特性使此类事件成为新兴类别的中年主要序列星类别的有吸引力的模型，这些模型被观察到显示瞬时的温暖灰尘云。此外，在双曲线轨道上的行星和返回的月球之间发生的较晚碰撞可能会使原本可居住的行星消毒。
Moons orbiting rocky exoplanets in compact orbits about other stars experience an accelerated tidal evolution, and can either merge with their parent planet or reach the limit of dynamical instability within a Hubble time. We review the parameter space over which moons become unbound, including the effects of atmospheric tides on the planetary spin. We find that such tides can change the final outcome from merger to escape, albeit over a limited parameter space. We also follow the further evolution of unbound moons, and demonstrate that the overwhelmingly most likely long-term outcome is that the unbound moon returns to collide with its original parent planet. The dust released by such a collision is estimated to reach optical depths approximately 0.001, exhibit characteristic temperatures of a few hundred degrees Kelvin, and last for a few thousand years. These properties make such events an attractive model for the emerging class of middle-aged main sequence stars that are observed to show transient clouds of warm dust. Furthermore, a late collision between a planet and a returning moon on a hyperbolic orbit may sterilise an otherwise habitable planet.
