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This article deals with the investigation of the Martian subsurface in the Utopia Planitia region using Zhurong’s ground-penetrating radar. The low-frequency data recorded along the overall path followed by the rover are processed thanks to a customized signal processing pipeline aiming on one side to minimize the artifacts in the radargrams and, on the other one, to obtain images of the subsoil that aid the following analysis and interpretation stage. The images reveal a three-layer structure beneath the landing area up to the depth of ~40 m. The general scattering characteristics indicate the presence of $5~\sim ~8$ -m regolith, $2~\sim ~3$ -m fine materials, and $15~\sim ~30$ m embedded with blocks generating a significant electromagnetic scattering. The existence of an upward decrease in grain size is resulted from long-term weathering and repeated impacts or the occurrence of flood events. The radargrams depict a distinctive local enhancement of the scattering at the end of the rover route from Sol 292 to Sol 325. Analysis of the layout of barchan dunes and the distribution of craters suggests that the resurfacing activity is the result of a complex combination of tectonic activities and impact events.

Orbital observations suggest that Mars underwent a recent ‘ice age’ (roughly 0.4–2.1 million years ago), during which a latitude-dependent ice-dust mantle (LDM)1,2was emplaced. A subsequent decrease in obliquity amplitude resulted in the emergence of an ‘interglacial period’1,3during which the lowermost latitude LDM ice4–6was etched and removed, returning it to the polar cap. These observations are consistent with polar cap stratigraphy1,7, but lower- to mid-latitude in situ surface observations in support of a glacial–interglacial transition that can be reconciled with mesoscale and global atmospheric circulation models8is lacking. Here we present a suite of measurements obtained by the Zhurong rover during its traverse across the southern LDM region in Utopia Planitia, Mars. We find evidence for a stratigraphic sequence involving initial barchan dune formation, indicative of north-easterly winds, cementation of dune sediments, followed by their erosion by north-westerly winds, eroding the barchan dunes and producing distinctive longitudinal dunes, with the transition in wind regime consistent with the end of the ice age. The results are compatible with the Martian polar stratigraphic record and will help improve our understanding of the ancient climate history of Mars9.

The Chang'E-6 (CE-6) mission successfully achieved return of the first samples from the far side of the Moon. The sampling site of CE-6 is located in the South Pole-Aitken (SPA) basin—the largest, deepest and oldest impact basin on the Moon. The 1935.3 g of CE-6 lunar samples exhibit distinct characteristics compared with previous lunar samples. This study analyses the physical, mineralogical, petrographic and geochemical properties of CE-6 lunar scooped samples. The CE-6 soil has a significantly lower bulk density (0.983 g/cm3) and true density (3.035 g/cm3) than the Chang'E-5 (CE-5) samples. The grain size of the CE-6 soil exhibits a bimodal distribution, indicating a mixture of different compositions. Mineralogically, the CE-6 soil consists of 32.6% plagioclase (anorthite and bytownite), 19.7% augite, 10% pigeonite and 3.6% orthopyroxene, and with low content of olivine (0.5%) but high content of amorphous glass (29.4%). Geochemically, the bulk composition of CE-6 soil is rich in Al2O3(14%) and CaO (12%) but low in FeO (17%), and trace elements of CE-6 soil such as K (∼630 ppm), U (0.26 ppm), Th (0.92 ppm) and rare-earth elements are significantly lower than those of the lunar soils within the Procellarum KREEP Terrane. The local basalts are characterized by low-Ti (TiO2, 5.08%), low-Al (Al2O39.85%) and low-K (∼830 ppm), features suggesting that the CE-6 soil is a mixture of local basalts and non-basaltic ejecta. The returned CE-6 sample contains diverse lithic fragments, including local mare basalt, breccia, agglutinate, glasses and leucocrate. These local mare basalts document the volcanic history of the lunar far side, while the non-basaltic fragments may offer critical insights into the lunar highland crust, SPA impact melts and potentially the deep lunar mantle, making these samples highly significant for scientific research.

Over 60 years of spacecraft exploration has revealed that the Earth’s Moon is characterized by a lunar crust1dominated 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) basin3on 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 crater5,6to 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)7onboard 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 context6suggests 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. Initial spectral observations by China’s Chang’E-4 far-side lunar rover suggest the presence of materials that may originate from the Moon’s mantle.

On May 15, 2021, Tianwen-1 successfully landed in the Utopia Planitia of Mars, and its rover Zhurong began to carry out an in-situ science exploration of the Mars surface. To determine the location, driving direction, and exploration targets of the rover, it is necessary to provide decision support for the in-situ science exploration of the rover and ensure the achievement of the scientific objectives, which pose significant challenges to the ground science team. Based on the classical research on Lunar and planetary localization, navigation and exploration target selection, and the recent study of pan-location cartographic theory, a pan-location mapping method for an in-situ rover exploration is proposed. In addition, a pan-location reference system, mapping data model, and mapping method are designed to realize the localization and visualization of the landing platform, rover, and exploration targets. The mapping method has been successfully applied to the localization, navigation, and science exploration of the target selection involved in the in-situ exploration of the Zhurong rover. The results of this study not only provide vital support to the implementation of the Tianwen-1 mission; they can also be used as instructions for other future in-situ Lunar and planetary exploration missions.

Forty-five years after the Apollo and Luna missions returned lunar samples, China's Chang’E-5 (CE-5) mission collected new samples from the mid-latitude region in the northeastern Oceanus Procellarum of the Moon. Our study shows that 95% of CE-5 lunar soil sizes are found to be within the range of 1.40–9.35 μm, while 95% of the soils by mass are within the size range of 4.84–432.27 μm. The bulk density, true density and specific surface area of CE-5 soils are 1.2387 g/cm3, 3.1952 g/cm3and 0.56 m2/g, respectively. Fragments from the CE-5 regolith are classified into igneous clasts (mostly basalt), agglutinate and glass. A few breccias were also found. The minerals and compositions of CE-5 soils are consistent with mare basalts and can be classified as low-Ti/low-Al/low-K type with lower rare-earth-element contents than materials rich in potassium, rare earth element and phosphorus. CE-5 soils have high FeO and low Mg index, which could represent a new class of basalt.The CE-5 sample is consistent with weathered mare basalts in mineralogy and petrochemistry, and is classified as low-Ti/low-Al/low-K type with lower REE (rare earth element) contents than KREEP (potassium, rare earth element, and phosphorus). This new sample characterized by high FeO and low Mg index could represent a new lunar basalt.

Chang'E‐4, with the Yutu‐2 rover, is the first lunar probe to successfully land and conduct a tour on the far side of the Moon from early 2019. We analyze the physical and mechanical characteristics of lunar soil through the in situ terrain data collected by the panoramic camera onboard the Yutu‐2 rover. With the slip ratio and wheel sinkage obtained by the derived Digital Orthophoto Map (DOM) and Digital Elevation Model (DEM), the mechanical parameters of lunar soil are derived from the slip‐sinkage model. These mechanical parameters and wheel size of the rover are used to obtain the pressure‐sinkage curves, which can estimate the lunar soil strength. The experimental results indicate that the soil strength at the Chang'E‐4 landing site is much higher than that at the Chang'E‐3 landing site. The discrepancies in lunar soil strength between the two landing sites may be related to the local surface topography and degree of space weathering. The knowledge of the physical and mechanical characteristics of lunar soil is of fundamental importance because it is the basis for mineral resource exploration and engineering activity aimed at the construction of lunar bases. The Chang'E‐4 landing site is within the mare floor of the Von Kármán crater inside the South Pole‐Aitken (SPA) basin. The ejecta from the nearby impact craters has covered the Chang'E‐4 landing area. Besides, the lunar soil of the Chang'E‐4 landing area has been relatively mature. Here, a method of analyzing the characteristics of lunar soil is introduced to provide an opportunity to understand the physical and mechanical properties of the mature lunar soil at the Chang'E‐4 landing site. With the terrain data collected by the panoramic camera onboard the Yutu‐2 rover, we can get the relationship curve of the interaction between the rover wheels and lunar soil, such as the pressure‐sinkage curve. The pressure‐sinkage curves can intuitively reflect the discrepancies of lunar soil strength at the Chang'E‐4 and Chang'E‐3 landing sites, which may bear a big relationship to the local surface morphology and degree of space weathering. The slip ratio can be estimated by Digital Orthophoto Map and the wheel sinkage can be derived from Digital Elevation ModelThe pressure‐sinkage curves can intuitively reflect the discrepancies of lunar soil strength at different landing sitesThe lunar soil strength at the Chang'E‐4 landing site nearby is higher than that at the Chang'E‐3 landing site