Moon samples from LUNA-24 mission to resolve the role of iron in regolith lunar soil with submicron Synchrotron Mössbauer Spectroscopy

In this study we propose to use the Synchrotron Mössbauer Source (SMS) to characterize the multitudes of complex and predominant Fe0, FeII and FeIII phases found in single microscopic (< 70 µm) grains of Luna-24 regolith samples to gain novel knowledge about their origin and formation. This samples were sourced from the sample return mission “Luna-24” in 1976. Recently there has been much debate about the origin and formation mechanism of nano particular Fe0 and FeIII respectively. The overall concentration of both phases is too low in the powdered Luna-24 sample which makes the focussed study of them difficult. By studying single grains rich in Fe instead of the diluted powder it is expected to gain novel knowledge of the occurring phases and their formation. By using SMS it is possible to do spatially resolved measurements of the single grains. This non-destructive method provides much more detail into formation processes, impossible without SMS.