Characteristic space weathering in lunar regolith. (a) Schematic showing SW implantation and surface alteration in lunar regolith. (b) Diagram of laboratory SSW generation using ﹩{{{\rm{D}}}_{2}}^{+}﹩ (1 keV per D atom) with low-energy electrons for charge balancing in the vacuum chamber (see Section 2.1). Ilmenite is mounted on a translation stage for a series of exposures (Table 1). (c) Atomic-scale model illustrating the incorporation of npFe⁰, planar defects, and vesicles within an ilmenite structure. (d) HAADF image showing an example of a space-weathered rim in ilmenite from Apollo soil 71501.