The successful impact of NASA’s DART mission with Dimorphos, the secondary body of binary asteroid system (65803) Didymos, altered the attitude, shape, and orbit of Dimorphos. In addition to perturbing the immediate short-term dynamics of the system, these changes have major implications for the binary Yarkovsky–O’Keefe–Radzievskii–Paddack (BYORP) effect and resulting long-term secular evolution. In this study, we assess the range of possible reshaping-induced changes in BYORP. We produce high-fidelity numerical simulations of the orbit-attitude coupled tidal-BYORP dynamical evolution of the Didymos system to constrain how the secular evolution changed from its preimpact behavior. We find that the nature of the dynamics is highly dependent on a variety of initial conditions and assumptions, and it is difficult to fully predict how the system will secularly evolve following the impact. Rather, we provide a range of feasible possibilities within the bounds of observations and current best estimates of the Didymos system parameters. ESA’s Hera mission will help reduce uncertainties surrounding the postimpact state and shape of Dimorphos in 2027, allowing our predictions of the secular evolutionary effects and long-term fate of the Didymos system to be better refined.

中文翻译：

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双小行星系统的长期动力学演化 (65803) Didymos Post-DART

NASA 的 DART 任务成功撞击了 Dimorphos（双小行星系统 (65803) Didymos 的次级天体），改变了 Dimorphos 的姿态、形状和轨道。除了扰乱系统的短期动态之外，这些变化还对二元雅科夫斯基-奥基夫-拉齐耶夫斯基-帕达克（BYORP）效应以及由此产生的长期长期演化产生重大影响。在本研究中，我们评估了 BYORP 重塑可能引起的变化范围。我们对 Didymos 系统的轨道-姿态耦合潮汐-BYORP 动力学演化进行了高保真数值模拟，以约束长期演化如何改变其撞击前的行为。我们发现动力学的性质高度依赖于各种初始条件和假设，并且很难完全预测系统在撞击后将如何长期演化。相反，我们在观察范围内和 Didymos 系统参数的当前最佳估计范围内提供了一系列可行的可能性。ESA 的赫拉任务将有助于减少 2027 年 Dimorphos 撞击后状态和形状的不确定性，使我们能够更好地完善对 Didymos 系统的长期进化影响和长期命运的预测。