论文标题
重新思考巨型行星不稳定性在地球形成模型中的作用
Rethinking the role of the giant planet instability in terrestrial planet formation models
论文作者
论文摘要
在过去的几十年中，计算能力和数值方法论的进步引发了对陆地行星形成晚期的动态研究的产量。在其他特殊的内部太阳系质量中，模拟在钙化铝富含钙富含钙的包含（CAI）之后，在地球化学上推断出<10 Myr的地球化学推断的积聚时间尺度（CAIS）的模拟能力被认为是判断进化假设的金标准。目前，许多独立的模型能够始终如一地产生类似火星的行星，并同时满足各种重要的观察和地球化学约束。但是，所有模型仍然必须说明巨型行星迁移和轨道不稳定时代的影响。动力学和宇宙化学约束表明的事件表明，在卵形气体扩散后的前100个MYR中发生。如果不稳定性发生在此窗口的前几个Myr中，则干扰可能会影响火星的大部分生长。在此手稿中，我们将注意力转向了t = 50 Myr后不稳定的情况。具体而言，我们模拟了通过以前的胚胎积聚模型生成的三个几乎组装的陆地系统的不稳定性影响，并包含三个具有轨道内部轨道内部的大型原始空间，以收集〜Mars-Mas-Mass胚胎和碎屑。尽管不稳定性始终触发月球形成的影响并有效地从模型中的火星区域中去除过多的材料，但我们发现我们的最终系统过于动态兴奋，没有火星和汞类似物。因此，我们得出的结论是，虽然可能，但我们的情况比不稳定性发生的情况要么难以置信，或者在地球和金星轨道的动态兴奋得多的时候。
Advances in computing power and numerical methodologies over the past several decades sparked a prolific output of dynamical investigations of the late stages of terrestrial planet formation. Among other peculiar inner solar system qualities, the ability of simulations to reproduce the small mass of Mars within the planets' geochemically inferred accretion timescale of <10 Myr after the appearance of calcium aluminum-rich inclusions (CAIs) is arguably considered the gold standard for judging evolutionary hypotheses. At present, a number of independent models are capable of consistently generating Mars-like planets and simultaneously satisfying various important observational and geochemical constraints. However, all models must still account for the effects of the epoch of giant planet migration and orbital instability; an event which dynamical and cosmochemical constraints indicate occurred within the first 100 Myr after nebular gas dispersal. If the instability occurred in the first few Myr of this window, the disturbance might have affected the bulk of Mars' growth. In this manuscript, we turn our attention to a scenario where the instability took place after t=50 Myr. Specifically, we simulate the instability's effects on three nearly-assembled terrestrial systems that were generated via previous embryo accretion models and contain three large proto-planets with orbits interior to a collection of ~Mars-mass embryos and debris. While the instability consistently triggers a Moon-forming impact and efficiently removes excessive material from the Mars-region in our models, we find that our final systems are too dynamically excited and devoid of Mars and Mercury analogs. Thus, we conclude that, while possible, our scenario is far more improbable than one where the instability either occurred earlier, or at a time where Earth and Venus' orbits were far less dynamically excited.
