A new analysis of lunar soil from China\u2019s Chang\u2019e-6 mission has revealed something scientists didn\u2019t expect to find on the moon \u2013 tiny grains of iron rust. <\/p>\n
Until now, the moon was believed to lack the oxygen conditions needed for iron oxidation, so the discovery challenges long-standing views of lunar surface chemistry and may help explain mysterious magnetic anomalies detected in several regions.<\/p>\n
The findings, published in the peer-reviewed journal Science Advances, come from a research team led by Shandong University with support from the Institute of Geochemistry of the Chinese Academy of Sciences and Yunnan University.\u00a0<\/p>\n
The team identified micrometre-scale crystals of hematite and maghemite, both forms of iron oxide, within the Chang\u2019e-6 samples<\/a> \u2013 a discovery that suggests previously unknown surface processes may have been shaping the moon for billions of years.<\/p>\n Discovery challenges decades-old assumption<\/p>\n For decades, scientists believed the moon<\/a> lacked the conditions needed for iron oxidation, making iron oxides virtually nonexistent on its surface. Even though the Apollo missions detected some ferric iron\u2013bearing materials, such as magnetite and iron hydroxides, the discovery was quickly dismissed.<\/p>\n A landmark study in 1971 argued that these compounds could not remain stable on the lunar surface and were most likely the result of contamination after the samples returned to Earth. This view shaped scientific thinking for more than half a century, reinforcing the idea that the moon was a dry, highly reduced environment with no natural pathway for iron to rust, the South China Morning Post reported<\/a>.<\/p>\n That assumption began to crumble in recent years as remote sensing data and lunar samples suggested that iron oxidation may be more common on the moon than once believed. Since 2020, observations from the Moon Mineralogy Mapper have shown widespread hematite \u2013 a highly oxidised mineral \u2013 at high lunar latitudes.\u00a0<\/p>\n Then in 2022, advanced microscopic analysis of Chang\u2019e-5 samples revealed traces of nanophase magnetite, adding further evidence that oxidation can occur on the lunar surface.<\/p>\n Samples show rust is intrinsic to the moon\u2019s geology<\/p>\n By studying the Chang\u2019e-6 samples returned in June last year, Chinese scientists identified micron-scale hematite grains for the first time, demonstrating that these iron oxides are a natural part of the moon\u2019s geology. To understand how ferric iron forms on the moon, the researchers examined several possible mechanisms and ruled out some alternatives.\u00a0<\/p>\n<\/p>\n