In Situ Synthesis of Agglutinitic Glass and Np‐Fe ⁰ in a Chang'E‐5 Lunar Regolith Simulant for Multi‐Scale High Fidelity

ABSTRACT Conventional lunar regolith simulants lack the agglutinitic glass and nanophase metallic iron (np‐Fe 0 ) that define mature lunar regolith. Here, we presented WUT‐1, a high‐fidelity Chang'E‐5 simulant. Its development marked a critical advance by achieving, for the first time, the direct in situ synthesis of agglutinitic glass with embedded np‐Fe 0 , simulating the thermal processes of meteorite impacts. This process authentically recreated the natural microstructure of lunar regolith—partially melting agglutinating unmelted minerals. The WUT‐1 simulant quantitatively replicated the mineralogy and moderate‐Ti, low‐Al 2 O 3 chemistry of Chang'E‐5 regolith. Its reflectance spectrum exhibited a characteristic asymmetric near 1 µm absorption band, indicative of augite, alongside substantial np‐Fe 0 ‐induced darkening and reddening. Particle‐size distribution was well‐sorted, with a median grain size deviating by less than 10% from Chang'E‐5 regolith, while its thermal stability and distinct glass transition mirrored key physicochemical properties of lunar regolith. These properties established WUT‐1 as a high‐precision analog for lunar science and ISRU testing.