Overview
- A team from IGCAS and Shandong University identified micron-scale hematite (α‑Fe2O3) and maghemite (γ‑Fe2O3) in soil returned from the South Pole–Aitken Basin by China's Chang'e‑6 mission.
- Science Advances published the findings on November 14, providing direct mineralogical evidence of highly oxidized iron phases in lunar material.
- Electron microscopy, electron energy loss spectroscopy and Raman spectroscopy confirmed the crystal structures and lunar origin of the grains, ruling out terrestrial contamination.
- Researchers propose that large impacts created brief high‑oxygen‑fugacity vapor conditions that oxidized iron released from minerals such as troilite and deposited it as micron-sized Fe2O3.
- The minerals occur alongside magnetite, reinforcing prior hints from Chang'e‑5 and remote sensing and offering new clues to persistent lunar magnetic anomalies and the Moon’s redox evolution.