Resolution of the lunar hydrogen enigma
Resolution of the lunar hydrogen enigma
复制标题
解决月球氢之谜
DOI：
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发表时间：
2011
期刊：
影响因子：
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通讯作者：
R. Hodges
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文献类型：
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作者：
R. Hodges
IBEX 和 Chandrayaan-1 航天器上的仪器最近发现从月球逸出的大量高能氢原子通量，这表明关于太阳风与月球风化层相互作用的常识存在缺陷，这些常识在试图解释阿波罗 17 号远紫外光谱仪未能检测到月球外逸层中中性 H 时盛行。通过将反射的高能中性氢和质子的模拟光谱与月船一号的类似中性光谱和辉夜号任务的质子数据进行比较，测试了太阳风与月球风化层表面相互作用的新理论。总体而言，该理论表明，大约 1% 入射到月球风化层表面的太阳风质子以高能质子的形式退出，大约 98.5% 以具有超逃逸速度的中性 H 形式退出。剩下的 0.5% 以亚逃逸速度的中性氢原子形式存在，形成一个脆弱的外逸层，与阿波罗 17 号观测所允许的莱曼-α 水平相一致。
The recent discovery, by instruments on the IBEX and Chandrayaan‐1 spacecraft, of significant fluxes of energetic hydrogen atoms escaping from the moon suggests that there are flaws in the common wisdom regarding the interaction of solar wind with lunar regolith that have prevailed in attempts to explain the failure of the Apollo 17 far‐ultraviolet spectrometer to detect neutral H in the lunar exosphere. A new theory for the interaction of solar wind with the lunar regolith surface is tested by comparing simulated spectra of reflected energetic neutral hydrogen and protons with analogous neutral spectra from Chandrayaan‐1 and proton data from the Kaguya mission. Overall, the theory indicates that roughly 1% of solar wind protons incident on the lunar regolith surface exit as energetic protons, and about 98.5% exit as neutral H with super‐escape speeds. The remaining 0.5%, which exit as neutral H atoms with sub‐escape speeds, form a tenuous exosphere that is compatible with the levels of Lyman‐α allowed by Apollo 17 observations.