William T. Reach

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The question of whether water is present on the Moon and how it might arise has long been a subject of debate (Arnold 1979; Crotts 2011). Most lunar rocks and minerals contain very little hydrogen (Albarède et al. 2015), though there are notable exceptions that are of high interest (McCubbin et al. 2015). The lunar surface is covered by regolith, a fragmental layer of debris formed by repeated meteorite impact (McKay et al. 1991), which is exposed to hydrogen from the space environment.