近日，美国亚利桑那大学Jeffrey C. Andrews-Hanna团队揭示了月球南极-艾特肯盆地南向撞击形成岩浆海。这一研究成果于2025年10月8日发表在《自然》杂志上。

古老的南极-艾特肯撞击盆地为人们理解月球演化提供了关键数据——它形成于月球历史最早的前酒海纪时期，比任何已知撞击盆地挖掘得更深，且位于人类认知相对有限的月球背面，而非已被充分探索的正面。

研究组通过分析盆地轮廓的锥度特征，以及向南侧逐渐过渡的地形与地壳厚度变化，证实撞击轨迹为自北向南，与既往假设相反。盆地西南部广泛分布的富钍富铁溅射物沉积，表明撞击部分挖掘了晚期岩浆洋的熔融物质。这些观测结果说明，撞击发生时富钍岩浆洋熔融体仅存于盆地西南半部下方，这符合关于全球岩浆洋向正面风暴洋富钾稀土磷地区的局部富集过渡的理论预测。这些发现对即将开展的"阿耳忒弥斯"月球南极载人探测计划具有重要指导意义，因为现有勘测已确认拟着陆区正位于该盆地的撞击溅射范围下沿及富钍溅射沉积层之上。

附：英文原文

Title: Southward impact excavated magma ocean at the lunar South Pole–Aitken basin

Author: Andrews-Hanna, Jeffrey C., Bottke, William F., Broquet, Adrien, Evans, Alexander J., Gowman, Gabriel, Johnson, Brandon C., Keane, James T., Levin, Janette N., Mallik, Ananya, Marchi, Simone, Moruzzi, Samantha A., Roy, Arkadeep, Wakita, Shigeru

Issue&Volume: 2025-10-08

Abstract: The ancient South Pole–Aitken impact basin provides a key data point for our understanding of the evolution of the Moon, as it formed during the earliest pre-Nectarian epoch of lunar history1, excavated more deeply than any other known impact basin2,3 and is found on the lunar far side, about which less is known than the well-explored near side. Here we show that the tapering of the basin outline and the more gradual topographic and crustal thickness transition towards the south support a southward impact trajectory, opposite of that commonly assumed. A broad thorium-rich and iron-rich ejecta deposit southwest of the basin is consistent with partial excavation of late-stage magma ocean liquids. These observations indicate that thorium-rich magma ocean liquids persisted only beneath the southwestern half of the basin at the time of impact, matching predictions for the transition from a global magma ocean to a local enrichment of potassium, rare-earth elements and phosphorus (KREEP) in the near-side Procellarum KREEP Terrane. These results have important implications for the upcoming human exploration of the lunar south pole by Artemis, as proposed landing sites are now recognized to sit on the downrange rim and thorium-rich impact ejecta of the basin.

DOI: 10.1038/s41586-025-09582-y

Source: https://www.nature.com/articles/s41586-025-09582-y