Discovery of crystalline Fe <sub>2</sub> O <sub>3</sub> in returned lunar soils
Lunar materials were believed to have formed and been preserved in a reducing environment, with only Fe<sup>2+</sup> and Fe<sup>0</sup> present. Native oxidized minerals, such as hematite, have not been validated in previously returned lunar samples. In this work, we report the discovery of micrometer-scale crystalline Fe<sub>2</sub>O<sub>3</sub> in the forms of hematite (α-Fe<sub>2</sub>O<sub>3</sub>) and maghemite (γ-Fe<sub>2</sub>O<sub>3</sub>) overgrowing troilite in the recently returned Chang'e-6 (CE6) lunar soils. It is possible that impact-induced oxygen release created localized micrometer-scale regions of elevated oxygen fugacity, facilitating the formation of Fe<sub>2</sub>O<sub>3</sub> at temperatures between ~700° and 1000°C. This finding provides credible evidence for the presence of Fe<sub>2</sub>O<sub>3</sub> on the lunar surface, challenging the traditional understanding of lunar surface redox states. In addition, the Fe<sub>2</sub>O<sub>3</sub> in the form of maghemite may be the mineralogical reason for the generation of the magnetic anomalies observed around the South Pole-Aitken basin.
Authors
- X. Lu (ORCID: https://orcid.org/0000-0002-5274-5069)
- Y.G. Liu (ORCID: https://orcid.org/0009-0005-1778-9313)
- Xiaohui Fu (ORCID: https://orcid.org/0000-0002-8818-7345)
- Le Qiao (ORCID: https://orcid.org/0000-0002-6180-2344)
- Zongcheng Ling (ORCID: https://orcid.org/0000-0002-9260-5765)
- Xiaojia Zeng (ORCID: https://orcid.org/0000-0002-6536-779X)
- Rui Li (ORCID: https://orcid.org/0000-0002-4602-4556)
- Haijun Cao (ORCID: https://orcid.org/0000-0003-0054-9557)
- Chen Li (ORCID: https://orcid.org/0009-0002-2759-8359)
- Jian Chen (ORCID: https://orcid.org/0000-0003-3759-0254)
- Yang Li (ORCID: https://orcid.org/0000-0002-5456-6603)
- Jianzhong Liu (ORCID: https://orcid.org/0000-0002-8324-3782)
- Changqing Liu (ORCID: https://orcid.org/0000-0002-1059-6528)
- Ziyi Jia (ORCID: https://orcid.org/0009-0005-9094-6178)
- Yanqing Xin (ORCID: https://orcid.org/0000-0003-3702-6792)
- Ying‐Bo Lu (ORCID: https://orcid.org/0000-0001-7799-8751)
- Can Bin Yin (ORCID: https://orcid.org/0009-0002-5844-0802)
Institutions
- Yunnan University (CN)
- Chinese Academy of Sciences (CN)
- Institute of Space Sciences (ES)
- Institute of Geochemistry (CN)
Publication Details
- Journal
- Science Advances
- Published
- 2025-11-14
- DOI
- https://doi.org/10.1126/sciadv.ady5169
- Citations
- 3
- Primary Topic
- Planetary Science and Exploration
- Type
- article
- Field-Weighted Citation Impact
- 3.46
Funders
- National Key Research and Development Program of China