Kuiper带天体的原始分布模拟

Simulations for Original Distribution of KBOs

用包括太阳、8颗大行星、冥王星和UB313以及无质量实验粒子在内的Ⅳ体问题的天体动力学模型,取当前观测的天体轨道根数为初始条件,对具有确定轨道根数的551个Kuiper主带内的小天体进行了10亿年的轨道反演数值模拟.结果显示:当前观测的这些Kuiper天体中的1/3以上在10亿年前就位于该区域,少部分位于海王星轨道之内,其他在50AU之外;在4.5亿年前,整个Kuiper主带内的天体呈较好的正态分布,海王星3:2共振带内没有像今天这样的天体聚集现象.

Using N-body dynamical model including the Sun, 8 planets, Pluto, UB313 and massless particles without masses, we simulate the orbital evolution of 551 Kuiper belt objects （KBOs） whose parameters are now determined. The initial conditions of the simulations are their current observational orbital parameters. The integral time is retrograde, from now to -10 × 10^8yrs. The results show that before 10 × 10^8yrs, more then 1/3 of the now observational KBOs had resided in the region of the Kuiper main belt, a few located inner Neptune orbit, and rest distributed outer 50AU; before 4.5 × 10^8yrs, the distribution of objects in the Kuiper main belt was normal, no large numbers of objects congregated in Neptune 3：2 resonance.