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Impact-driven disproportionation origin of nanophase iron particles in Chang’e-5 lunar soil sample


Abundant nanophase iron (np-Fe0) is ubiquitously formed on the surface of the Moon and other airless bodies through space weathering processes, and plays a dominant role in transforming the optical properties of the lunar surface. The main sources of np-Fe0 are usually considered to be evaporative deposition or ion-reduction processes. Here we show that disproportionation reactions triggered by micrometeorite impacts can be the main contributor to np-Fe0 formation. We measured the valence states of iron in the microcraters on a fine-grained Chang’e-5 sample (number CE5C0200YJFM00302) and found the presence of np-Fe0 and associated Fe3+ in the amorphous mixture of olivine, which can be explained by the disproportionation reaction of Fe2+ during microimpacts. The chemical composition of the residual impactor suggested that it was formed by a secondary low-velocity impact on lunar anorthite. As the whole process was dominated by impact events without the contribution from the solar wind, these findings inform us on weathering mechanisms on regions or bodies that do not experience a strong solar wind component, such as permanently shadowed areas or outer Solar System bodies.

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Fig. 1: Secondary electron images of CE5C0200YJFM00302 particles captured by FIB-SEM.
Fig. 2: TEM image of the longitudinal section of a FIB slice containing microcraters on an olivine grain.
Fig. 3: The compositional data and speculation of the source of microcraters.
Fig. 4: Microscopic morphology and valence states of np-Fe0 in microcrater 1.
Fig. 5: Gibbs free energy of reactions.

Data availability

All data generated and analysed in this study are included in the article and its Supplementary Information. A complete dataset for this study is also available at Mendeley Data at Source data are provided with this paper.


  1. Pieters, C. M. & Noble, S. K. Space weathering on airless bodies. J. Geophys. Res. Planets 121, 1865–1884 (2016).

    Article  ADS  Google Scholar 

  2. Sasaki, S., Nakamura, K., Hamabe, Y., Kurahashi, E. & Hiroi, T. Production of iron nanoparticles by laser irradiation in a simulation of lunar-like space weathering. Nature 410, 555–557 (2001).

    Article  ADS  Google Scholar 

  3. Hapke, B. Space weathering from Mercury to the asteroid belt. J. Geophys. Res. Planets 106, 10039–10073 (2001).

    Article  ADS  Google Scholar 

  4. Anand, M. et al. Space weathering on airless planetary bodies: clues from the lunar mineral hapkeite. Proc. Natl Acad. Sci. USA 101, 6847–6851 (2004).

    Article  ADS  Google Scholar 

  5. Noguchi, T. et al. Incipient space weathering observed on the surface of Itokawa dust particles. Science 333, 1121–1125 (2011).

    Article  ADS  Google Scholar 

  6. Ryan, E. V. Asteroid fragmentation and evolution of asteroids. Annu. Rev. Earth Planet. Sci. 28, 367–389 (2000).

    Article  ADS  Google Scholar 

  7. Binzel, R. P. et al. Earth encounters as the origin of fresh surfaces on near-Earth asteroids. Nature 463, 331–334 (2010).

    Article  ADS  Google Scholar 

  8. Dai, Z. et al. Possible in situ formation of meteoritic nanodiamonds in the early solar system. Nature 418, 157–159 (2002).

    Article  ADS  Google Scholar 

  9. Pieters, C. et al. Distinctive space weathering on Vesta from regolith mixing processes. Nature 491, 79–82 (2012).

    Article  ADS  Google Scholar 

  10. Vernazza, P. et al. Compositional differences between meteorites and near-Earth asteroids. Nature 454, 858–860 (2008).

    Article  ADS  Google Scholar 

  11. Bottke, W. et al. Dating the Moon-forming impact event with asteroidal meteorites. Science 348, 321–323 (2015).

    Article  ADS  Google Scholar 

  12. Marchi, S. et al. High-velocity collisions from the lunar cataclysm recorded in asteroidal meteorites. Nat. Geosci. 6, 303–307 (2013).

    Article  ADS  Google Scholar 

  13. Vernazza, P., Binzel, R., Rossi, A., Fulchignoni, M. & Birlan, M. Solar wind as the origin of rapid reddening of asteroid surfaces. Nature 458, 993–995 (2009).

    Article  ADS  Google Scholar 

  14. Loeffler, M., Dukes, C. & Baragiola, R. Irradiation of olivine by 4 keV He+: simulation of space weathering by the solar wind. J. Geophys. Res. Planets 114, E03003 (2009).

    Article  ADS  Google Scholar 

  15. Dukes, C., Baragiola, R. & McFadden, L. Surface modification of olivine by H+ and He+ bombardment. J. Geophys. Res. Planets 104, 1865–1872 (1999).

    Article  ADS  Google Scholar 

  16. Laczniak, D. et al. Characterizing the spectral, microstructural, and chemical effects of solar wind irradiation on the Murchison carbonaceous chondrite through coordinated analyses. Icarus 364, 114479 (2021).

    Article  Google Scholar 

  17. Fazio, A. et al. Femtosecond laser irradiation of olivine single crystals: experimental simulation of space weathering. Icarus 299, 240–252 (2018).

    Article  ADS  Google Scholar 

  18. Thompson, M. S., Zega, T. J., Becerra, P., Keane, J. T. & Byrne, S. The oxidation state of nanophase Fe particles in lunar soil: implications for space weathering. Meteorit. Planet. Sci. 51, 1082–1095 (2016).

    Article  ADS  Google Scholar 

  19. Frost, D. J. et al. Experimental evidence for the existence of iron-rich metal in the Earth’s lower mantle. Nature 428, 409–412 (2004).

    Article  ADS  Google Scholar 

  20. Guo, Z. et al. Evidence for the disproportionation of iron in a eucrite meteorite: implications for impact processes on Vesta. J. Geophys. Res. Planets 126, E006816 (2021).

    Article  Google Scholar 

  21. Kaluna, H., Ishii, H., Bradley, J., Gillis-Davis, J. & Lucey, P. Simulated space weathering of Fe- and Mg-rich aqueously altered minerals using pulsed laser irradiation. Icarus 292, 245–258 (2017).

    Article  ADS  Google Scholar 

  22. Keller, L. P., Berger, E. L., Zhang, S. & Christoffersen, R. Solar energetic particle tracks in lunar samples: a transmission electron microscope calibration and implications for lunar space weathering. Meteorit. Planet. Sci. 56, 1685–1707 (2021).

    Article  ADS  Google Scholar 

  23. Li, Q.-L. et al. Two billion-year-old volcanism on the Moon from Chang’e-5 basalts. Nature 600, 54–58 (2021).

    Article  ADS  Google Scholar 

  24. Hu, S. et al. A dry lunar mantle reservoir for young mare basalts of Chang’e-5. Nature 600, 49–53 (2021).

    Article  ADS  Google Scholar 

  25. Li, C. et al. Characteristics of the lunar samples returned by Chang’e-5 mission. Natl Sci. Rev. 9, nwab188 (2021).

    Article  Google Scholar 

  26. Matsumoto, T., Hasegawa, S., Nakao, S., Sakai, M. & Yurimoto, H. Population characteristics of submicrometer-sized craters on regolith particles from asteroid Itokawa. Icarus 303, 22–33 (2018).

    Article  ADS  Google Scholar 

  27. Noble, S., Keller, L., Christoffersen, R. & Rahman, Z. The microstructure of lunar micrometeorite impact craters. In Lunar and Planetary Science and Exploration. No. JSC-CN-35097 (2016).

  28. Thompson, M. S., Christoffersen, R., Zega, T. J. & Keller, L. P. Microchemical and structural evidence for space weathering in soils from asteroid Itokawa. Earth Planets Space 66, 1–10 (2014).

    Article  Google Scholar 

  29. Noguchi, T. et al. Space weathered rims found on the surfaces of the Itokawa dust particles. Meteorit. Planet. Sci. 49, 188–214 (2014).

    Article  ADS  Google Scholar 

  30. Spray, J. G. Frictional melting processes in planetary materials: from hypervelocity impact to earthquakes. Annu. Rev. Earth Planet. Sci. 38, 221–254 (2010).

    Article  ADS  Google Scholar 

  31. Hörz, F., Hartung, J. & Gault, D. Micrometeorite craters on lunar rock surfaces. J. Geophys. Res. 76, 5770–5798 (1971).

    Article  ADS  Google Scholar 

  32. Holsapple, K. A. The scaling of impact processes in planetary sciences. Annu. Rev. Earth Planet. Sci. 21, 333–373 (1993).

    Article  ADS  Google Scholar 

  33. Burgess, K. D., Stroud, R. M., Dyar, M. D. & McCanta, M. C. Submicrometer-scale spatial heterogeneity in silicate glasses using aberration-corrected scanning transmission electron microscopy. Am. Mineral. 101, 2677–2688 (2016).

    Article  ADS  Google Scholar 

  34. Keller, L. P. & McKay, D. S. Discovery of vapor deposits in the lunar regolith. Science 261, 1305–1307 (1993).

    Article  ADS  Google Scholar 

  35. Garvie, L. A. & Buseck, P. R. Ratios of ferrous to ferric iron from nanometre-sized areas in minerals. Nature 396, 667–670 (1998).

    Article  ADS  Google Scholar 

  36. Telfer, D. & Walker, G. Optical detection of Fe3+ in lunar plagioclase. Nature 258, 694–695 (1975).

    Article  ADS  Google Scholar 

  37. Burgess, K. & Stroud, R. Coordinated nanoscale compositional and oxidation state measurements of lunar space‐weathered material. J. Geophys. Res. Planets 123, 2022–2037 (2018).

    Article  ADS  Google Scholar 

  38. Shen, Y., Jester, S. B., Qi, T. & Reed, E. J. Nanosecond homogeneous nucleation and crystal growth in shock-compressed SiO2. Nat. Mater. 15, 60–65 (2016).

    Article  ADS  Google Scholar 

  39. Bale, C. W. et al. FactSage thermochemical software and databases. CALPHAD 26, 189–228 (2002).

    Article  Google Scholar 

  40. Bale, C. W. et al. Reprint of: FactSage thermochemical software and databases, 2010–2016. CALPHAD 55, 1–19 (2016).

    Article  ADS  Google Scholar 

  41. Cheng, X., Sun, T.-P. & Gordillo, L. Drop impact dynamics: impact force and stress distributions. Annu. Rev. Fluid Mech. 54, 57–81 (2021).

    Article  ADS  MATH  Google Scholar 

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We thank CNSA for providing access to the lunar sample CE5C0200YJFM00302. We also thank funding support from Strategic Priority Research Program of the Chinese Academy of Sciences grant XDB 41000000 (Y.L.); Natural Science Foundation of China grant 41931077; and Technical Advanced Research Project of Civil Space grant D020201, Youth Innovation Promotion Association CAS grant 2020395, and Key Research Program of Frontier Sciences, CAS, grant numbers ZDBS-SSW-JSC007-10 and QYZDY-SSW-DQC028 (Y.L.).

Author information

Authors and Affiliations



C.L. analysed the datasets and wrote the manuscript. Z.G. contributed to the TEM and EELS discussion. Y.L. contributed to the experimental design and manuscript discussion. K.T., K.W., X.L. J.L. and W.M. contributed to the manuscript discussions.

Corresponding authors

Correspondence to Yang Li or Kuixian Wei.

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Nature Astronomy thanks Leon Hicks and Kate Burgess for their contribution to the peer review of this work.

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Supplementary information

Supplementary Information

Supplementary Figs. 1–10 and Table 1.

Source data

Source Data Fig. 1

Unprocessed SEM images for Fig. 1.

Source Data Fig. 2

Unprocessed TEM images for Fig. 2.

Source Data Fig. 3

Unprocessed HAADF and EDS images for Fig. 3.

Source Data Fig. 4

Unprocessed HRTEM and HAADF images and EELS source data for Fig. 4.

Source Data Fig. 5

Source data for Fig. 5.

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Li, C., Guo, Z., Li, Y. et al. Impact-driven disproportionation origin of nanophase iron particles in Chang’e-5 lunar soil sample. Nat Astron 6, 1156–1162 (2022).

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