Chang'e-6 lunar soil holds rare γ-Fe iron, a magnetic time capsule

Researchers from HFIPS of the Chinese Academy of Sciences have identified face-centered cubic γ-Fe for the first time in natural lunar samples — impact glass from Chang'e-6 soil. Normally stable only at high temperatures, the phase survived thanks to rapid cooling, trace elements and the surrounding glassy matrix. The findings were published in PNAS.

• γ-Fe found for the first time in natural lunar samples from Chang'e-6 impact glass
• γ-Fe was the dominant iron form in both glass samples studied
• Larger γ-Fe particles form a stable single-vortex magnetic state
• Carbon traces, rapid cooling and glass shielding may stabilize the structure