Over 60 years of spacecraft exploration has revealed that the Earth’s Moon is characterized by a lunar crust1 dominated by the mineral plagioclase, overlying a more mafic (richer in iron and magnesium) mantle of uncertain composition. Both crust and mantle formed during the earliest stages of lunar evolution when late-stage accretional energy caused a molten rock (magma) ocean, flotation of the light plagioclase, sinking of the denser iron-rich minerals, such as olivine and pyroxene, and eventually solidification2. Very large impact craters can potentially penetrate through the crust and sample the lunar mantle. The largest of these craters is the approximately 2,500-kilometre-diameter South Pole-Aitken (SPA) basin3 on the lunar far side. Evidence obtained from orbiting spacecraft shows that the floor of the SPA basin is rich in mafic minerals4, but their mantle origin is controversial and their in situ geologic settings are poorly known. China’s Chang’E-4 lunar far-side lander recently touched down in the Von Kármán crater5,6 to explore the floor of the huge SPA basin and deployed its rover, Yutu-2. Here we report on the initial spectral observations of the Visible and Near Infrared Spectrometer (VNIS)7 onboard Yutu-2, which we interpret to represent the presence of low-calcium (ortho)pyroxene and olivine, materials that may originate from the lunar mantle. Geological context6 suggests that these materials were excavated from below the SPA floor by the nearby 72-km-diameter Finsen impact crater event, and transported to the landing site. Continued exploration by Yutu-2 will target these materials on the floor of the Von Kármán crater to understand their geologic context, origin and abundance, and to assess the possibility of sample-return scenarios.
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Reflectance data for CE4_0015 and CE4_0016 are provided in Source Data. The source data for the Chang’E-2 Digital Orthophoto Map and the Chang’E-4 Terrain Camera image (Fig. 1) are available from the Data Publishing and Information Service System of China’s Lunar Exploration Program (http://moon.bao.ac.cn). LSCC data are available from LSCC (http://www.planetary.brown.edu/relabdocs/LSCCsoil.html). Datasets generated or analysed during this study are available from the corresponding author upon reasonable request.
Publisher’s note: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Wieczorek, M. A. et al. The crust of the Moon as seen by GRAIL. Science 339, 671–675 (2013).
Wood, J. A., Dickey, J. S., Marvin, U. B. & Powell, B. N. Lunar anorthosites and a geophysical model of the Moon. Geochim. Cosmochim. Acta 1, 965–988 (1970).
Stuart-Alexander, D. E. Geologic Map of the Central Far Side of the Moon I-1047 (US Geological Survey, Denver, 1978).
Moriarty, D. P. III & Pieters, C. M. The character of South Pole Aitken basin: patterns of surface and subsurface composition. J. Geophys. Res. Planets 123, 729–747 (2018).
Li, C. L. et al. The Chang’e 3 mission overview. Space Sci. Rev. 190, 85–101 (2015).
Huang, J. et al. Geological characteristics of Von Kármán crater, northwestern South Pole Aitken basin: Chang’E 4 landing site region. J. Geophys. Res. Planets 123, 1684–1700 (2018).
He, Z. P. et al. Operating principles and detection characteristics of the visible and near-infrared imaging spectrometer in the Chang’E-3. Res. Astron. Astrophys. 14, 1567–1577 (2014).
Wieczorek, M. A. et al. The constitution and structure of the lunar interior. Rev. Mineral. Geochem. 60, 221–364 (2006).
Shearer, C. et al. Thermal and magmatic evolution of the Moon. Rev. Mineral. Geochem. 60, 365–518 (2006).
Tompkins, S. & Pieters, C. M. Mineralogy of the lunar crust: results from Clementine. Meteorit. Planet. Sci. 34, 25–41 (1999).
Yamamoto, S. et al. Possible mantle origin of olivine around lunar impact basins detected by SELENE. Nat. Geosci. 3, 533–536 (2010).
Pieters, C. M., Tompkins, S., Head, J. W. & Hess, P. C. Mineralogy of the mafic anomaly in the South Pole-Aitken basin: implications for excavation of the lunar mantle. Geophys. Res. Lett. 24, 1903–1906 (1997).
Prettyman, T. H. et al. Elemental composition of the lunar surface: analysis of gamma ray spectroscopy data from Lunar Prospector. J. Geophys. Res. 111, E12007 (2006).
Yamamoto, S. et al. Olivine-rich exposures in the South Pole-Aitken basin. Icarus 218, 331–344 (2012).
Garrick-Bethell, I. & Zuber, M. T. Elliptical structure of the lunar South Pole-Aitken basin. Icarus 204, 399–408 (2009).
Vaughan, W. M., Head, J. W., Wilson, L. & Hess, P. C. Geology and petrology of enormous volumes of impact melt on the Moon: a case study of the Orientale basin impact melt sea. Icarus 223, 749–765 (2013).
Vaughan, W. M. & Head, J. W. Impact melt differentiation in the South Pole-Aitken basin: some observations and speculations. Planet. Space Sci. 91, 101–106 (2014).
Pieters, C. M., Head, J. W., Gaddis, L., Jolliff, B. & Duke, M. Rock types of South Pole Aitken basin and extent of basaltic volcanism. J. Geophys. Res. Planets 106, 28001–28022 (2001).
Potter, R. W. K., Collins, G. S., Kiefer, W. S., McGovern, P. J. & Kring, D. A. Constraining the size of the South Pole-Aitken basin impact. Icarus 220, 730–743 (2012).
Melosh, H. J. et al. South Pole-Aitken basin ejecta reveal the Moon’s upper mantle. Geology 45, 1063–1066 (2017).
.Guo, H. & Wu, J. in Space Science and Technology in China: A Roadmap to 2050 (ed. Guo, H.) 99 (Chinese Academy of Sciences Science Press, Beijing, 2009).
US National Research Council. The Scientific Context for Exploration of the Moon (National Academies Press, Washington DC, 2007).
Moriarty, D. P. et al. Finsen and Alder: a compositional study of lunar central peak craters in the South Pole-Aitken basin. Lunar Planet. Sci. Conf. 42, 2564 (2011).
Ling, Z. et al. Correlated compositional and mineralogical investigations at the Chang′ E-3 landing site. Nat. Commun. 6, 8880 (2015).
Hapke, B. Space weathering from Mercury to the asteroid belt. J. Geophys. Res. Planets 106, 10039–10073 (2001).
Pieters, C. M. et al. Space weathering on airless bodies: resolving a mystery with lunar samples. Meteorit. Planet. Sci. 35, 1101–1107 (2000).
Klima, R. L., Dyar, M. D. & Pieters, C. M. Near infrared spectra of clinopyroxenes: effects of calcium content and crystal structure. Meteorit. Planet. Sci. 46, 379–395 (2011).
Klima, R. L., Pieters, C. M. & Dyar, M. D. Spectroscopy of synthetic Mg-Fe pyroxenes I: spin-allowed and spin-forbidden crystal field bands in the visible and near-infrared. Meteorit. Planet. Sci. 42, 235–253 (2007).
Sunshine, J. M., Pieters, C. M. & Pratt, S. F. Deconvolution of mineral absorption bands: an improved approach. J. Geophys. Res. Solid Earth 95, 6955–6966 (1990).
Sunshine, J. M. & Pieters, C. M. Estimating modal abundances from the spectra of natural and laboratory pyroxene mixtures using the modified Gaussian model. J. Geophys. Res. Planets 98, 9075–9087 (1993).
Nakamura, R. et al. Ultramafic impact melt sheet beneath the South Pole–Aitken basin on the Moon. Geophys. Res. Lett. 36, L22202 (2009).
Neumann, G. & Head, J. Geophysical characteristics of Von Kármán crater: Chang/E 4 landing site region. Lunar Planet. Sci. Conf. 50, 2132 (2019).
Liu, B. et al. Data processing and preliminary results of the Chang’E-3 VIS/NIR imaging spectrometer in-situ analysis. Res. Astron. Astrophys. 14, 1578–1594 (2014).
Wu, Y. Z. & Hapke, B. Spectroscopic observations of the Moon at the lunar surface. Earth Planet. Sci. Lett. 484, 145–153 (2018).
Wu, Y. Z. et al. The absolute reflectance and new calibration site of the Moon. Astron. J. 155, 213 (2018).
Savitzky, A. & Golay, M. J. Smoothing and differentiation of data by simplified least squares procedures. Anal. Chem. 36, 1627–1639 (1964).
Sunshine, J. M. & Pieters, C. M. Determining the composition of olivine from reflectance spectroscopy. J. Geophys. Res. Planets 103, 13675–13688 (1998).
Staid, M. I. et al. The mineralogy of late stage lunar volcanism as observed by the Moon Mineralogy Mapper on Chandrayaan-1. J. Geophys. Res. Planets 116, E00G10 (2011).
Besse, S. et al. Compositional variability of the Marius Hills volcanic complex from the Moon Mineralogy Mapper (M3). J. Geophys. Res. Planets 116, E00G13 (2011).
Clénet, H. et al. A new systematic approach using the Modified Gaussian Modal: insight for the characterization of chemical composition of olivines, pyroxenes and olivine-pyroxene mixtures. Icarus 213, 404–422 (2011).
Kanner, L. C., Mustard, J. F. & Gendrin, A. Assessing the limits of the Modified Gaussian Model for remote spectroscopic studies of pyroxenes on Mars. Icarus 187, 442–456 (2007).
This research was funded by the Chang’E-4 mission of CLEP. We thank the team members of the Ground Application and Research System (GRAS), who contributed to data receiving and preprocessing.
Nature thanks Rachel Klima and Patrick Pinet for their contribution to the peer review of this work.
Extended data figures and tables
Extended Data Fig. 1 Spectral comparison between CE4_0015, CE4_0016 and LSCC samples (continuum removed).
The red and blue lines represent CE4_0015 and CE4_0016. a, Comparison of CE4_0015 and CE4_0016 with mare soil (particle size <45 μm) samples: 10084, 12001, 12030, 15041, 15071, 70181, 71501, 79221. The 1-μm and 2-μm absorption bands of CE4_0015 and the 2-μm absorption band of CE4_0016 (dashed lines) obviously shifts to shorter wavelengths and differ considerably from the spectral features of the mare samples. b, Comparison of CE4_0015 and CE4_0016 with highland samples (particle size <45 μm): 14141, 14163, 14259, 14260, 61141, 61221, 62231, 64801, 67461, 67481. The 1-μm and 2-μm absorption bands of CE4_0015 and the 2-μm absorption band (dashed lines) of CE4_0016 resemble those of the highland samples. However, the 1-μm absorption band of CE4_0016 is more similar to that of basaltic soil, which can be attributed to elevated abundance of olivine (see main text). Source data
Extended Data Fig. 2 Parabola-fitting results for CE4_0015 and CE4_0016 1-μm and 2-μm absorption-band positions.
a, Reflectance of CE4_0015; the positions of the 1-μm and 2-μm bands are 949.2 nm and 1,985.9 nm, respectively. b, Reflectance of CE4_0016; the 1-μm- and 2-μm-band positions are 995.1 nm and 1,984.9 nm, respectively. The 2-μm-band centre assignment is tentative because of its weak absorption. The red and blue lines represent the wavelength ranges used for the parabola fitting of the 1-μm- and 2-μm-band centres, respectively.
Extended Data Fig. 3 MGM deconvolution results of CE4_0015 spectra using four different mineral assemblages.
a, LCP + HCP + OL. b, LCP + HCP + Plag. c, LCP + Plag. d, LCP + OL.
Extended Data Fig. 4 Content ratio HCP/(HCP + LCP) for CE4_0015 and CE4_0016, calculated by MGM deconvolution.
a, 1-μm result: 19% (CE4_0015) and 16% (CE4_0016). b, 2-μm results: 20% (CE4_0015) and 18% (CE4_0016). Data are from figure 7 of ref. 30, overlain on calibration lines (solid black line). Solid black symbols represent pyroxene samples of different grain size. The calibration line is defined by the relationship between the MGM-derived band-depth ratio of LCP/HCP and the content ratio of HCP/(HCP + LCP) measured in the laboratory for all grain sizes of the pyroxene samples. The MGM-derived band-depth ratios of LCP/HCP for CE4_0015 (red triangle) and CE4_0016 (green triangle) were projected onto the calibration line to estimate their corresponding content ratio of HCP/(HCP + LCP).
The results were derived from VNIS spectra, overlain on calibration lines defined by the relationship between the Fo value and the absorption-band positions of olivine of various compositions (data used to plot the calibration lines are from figure 4 of ref. 37).
a, Average M3 reflectance spectra obtained using five adjacent pixels with central pixel position (64, 4,927). b, Continuum-removed spectrum; 1-μm-band position, 930.1 nm; 2-μm-band position, 2,058.66 nm.