AI 中文总结
本文对2025-010D（猎鹰9号火箭上面级）开展地基表征，确认其关联特定发射任务，揭示其形状、自转周期变化及热控材料特征，预测其撞击月球背面的位置与参数，为近地空间天体识别提供基准。
AI 中文摘要
对月球探测的 renewed interest 正导致近地空间（地月之间）难以追踪的天体数量不断增加，其中部分天体最终会撞击月球。火箭上面级或失效任务载荷的最终命运往往未知且无规划。随着持续的月球探测将人类及基础设施部署于月表，确定这类天体的起源和物理特性将愈发重要。本文对2025-010D开展地基物理与动力学表征，该天体为猎鹰9号（Falcon 9）火箭上面级，预计于2026年8月5日撞击月球背面。对其轨道的反向推算可独立将该天体与“空中孤骑（Ghost Riders in the Sky）”发射任务关联；可见光与近红外光谱分析将其与天然天体区分，发现与航天器热控材料一致的吸收带。测光光变曲线证实其为细长形状，观测期间其约7分钟的自转周期出现了超过8秒的意外变化。我们预测其将以约2.4千米每秒的速度撞击贝尔（Bell）陨石坑与爱因斯坦（Einstein）陨石坑之间，产生直径约40米的陨石坑。由于其起源已被独立确认，2025-010D为识别和表征未来起源不明的近地空间天体提供了基准。
英文摘要
Renewed interest in lunar exploration is creating a growing population of poorly tracked cislunar objects, some of which will ultimately impact the Moon$^{1}$. The ultimate fate of rocket upper stages or failed mission payloads is often unknown and unplanned. Determining the origin and physical properties of such objects will become increasingly important as sustained lunar exploration places humans and infrastructure on the surface$^{2;3;4;5}$. Here we present a ground-based physical and dynamical characterization of 2025-010D, a Falcon 9 upper stage predicted to impact the lunar farside on 2026 August 05. Backward propagation of its orbit independently links the object to the ``Ghost Riders in the Sky'' launch, while visible and near-infrared spectroscopy distinguishes it from natural objects and reveals absorption bands consistent with spacecraft thermal control materials. Photometric lightcurves confirm its elongated shape and reveal an unexpected change of more than 8 s in its $\sim$7 min rotation period during observations. We predict an impact between Bell and Einstein craters at $\sim$2.4 km s$^{-1}$, producing a crater $\sim$40 m in diameter. Since its provenance is independently known, 2025-010D provides a benchmark for identifying and characterizing future cislunar objects of uncertain origin.
