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Schematic representation of the formation of a palaeoregolith layer trapped between distinct lava flow units that could be dated to bracket the window of regolith development and, thus, constrain the delivery interval of any preserved projectile debris: 1 A new lava flow is emplaced and cools. 2 Impactors immediately begin to develop a surficial regolith, where the post-basin epoch rate of gardening is estimated to have ranged from ~3 to 5 mm of new regolith per million years at ~3.8 Ga to be about 1 mm/Myr from ~3.5 Ga to the present day (Hörz et al. 1991). Impactor debris, solar wind particles, galactic cosmic rays and “exotic” material derived from elsewhere on the Moon (and perhaps elsewhere) are implanted. 3 The regolith layer, with its embedded historical record, is buried by a more recent lava flow, forming a palaeoregolith. The new lava flow may bake out some of the trapped volatiles and implanted solar wind from the palaeoregolith layer, though degassing and associated oxidization effects (similar to those processes described in Shearer et al. 2014; Joy et al. 2015; Treiman et al. 2016) will vary depending on the temperature of the new lava flow and thickness of the trapped regolith horizon (Fagents et al. 2010; Rumpf et al. 2013; Crawford et al. 2009). 4 The process begins again on the upper surface generating a younger surficial regolith. Modified from Crawford et al. (2007). This model could also be applicable for regolith units that are sandwiched between, or buried under, pyroclastic picritic glass bead deposits (McKay 2009) or buried under impact ejecta blankets (with the caveat that such ejecta emplacement may also contribute to a debris of ballistic sedimentation and mixing of the buried regolith layer) (McKay 2009)
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The Moon is an archive of impact cratering in the Solar System throughout the past 4.5 billion years. It preserves this record better than larger, more complex planets like the Earth, Mars and Venus, which have largely lost their ancient crusts through geological reprocessing and hydrospheric/atmospheric weathering. Identifying the parent bodies of...
Citations
... The environmental consequences (e.g., dust lofting, ejecta blanketing, flood basalts, rockfall; mountain-forming, etc.) of these impacts may also be inferred through orbital, field, and sample observations of impact craters (Bickel et al., 2020;Michaut & Pinel, 2018;Mukhametshin et al., 2018;Xie et al., 2020). The delivery and abundance of elements through impacts may also be determined and used to piece together a history of the chemical evolution of the lunar interior and crust (Barnes et al., 2016;Bottke et al., 2010;Joy et al., 2016Joy et al., , 2020Zhu et al., 2019). Finally, investigations and sampling of heavily impact-cratered terrain may also provide access to impact melt samples from other craters (Kring, 2007(Kring, , 2009Kring et al., 2005). ...
... Due to the high velocity of impact (e.g., Le Feuvre and Wieczorek, 2011) and resultant melting and/or vaporization, a projectile can impart its geochemical signature into the impact melt deposits it creates Morgan, Laul, et al., 1972;Ganapathy et al., 1974;Higuchi & Morgan, 1975;Gros et al., 1976;James, 1996James, , 2002Norman et al., 2002;Puchtel et al., 2008). However, some impactors completely or partially survive the lunar impact process intact, as evidenced by unmelted fragments of meteorites that have been found in lunar rocks and soils (Day et al., 2006;Jolliff et al., 1993;Joy et al., 2012Joy et al., , 2016Joy et al., , 2020McSween Jr, 1976;Rubin, 1997;Zolensky, 1997;Zolensky et al., 1996). When paired with a time of impact, these partially unmelted samples help to provide better geochemical and chronological constraints for models of Solar System dynamics and causes of proposed impact spikes to the Earth-Moon system (Cohen et al., 2000;Dalrymple & Ryder, 1993, 1996Kring & Cohen, 2002;Kring et al., 2005;Morbidelli et al., 2018;Norman et al., 2006;Tera et al., 1974;Turner et al., 1973;Ćuk et al., 2010). ...
The Artemis exploration zone is a geologically complex region likely to host some of the oldest and as‐yet‐unstudied materials on the Moon. We review six potential Artemis landing sites (001, 004, 007, 011, 102, and 105) within candidate Artemis III landing regions ”Connecting Ridge,“ “Peak Near Shackleton,” “Leibnitz Beta Plateau,” “de Gerlache Rim,” and “de Gerlache Rim 2.” Kaguya Spectral Profiler mineral data were used to determine the average lithological composition at each landing site. Potentially accessible geologic materials, their ages and significance, and appropriate application of radiometric chronometers are discussed in reference to return samples from each potential landing site. Chronological analyses of return samples from the Artemis exploration zone will enable the anchoring of the lunar impact flux curve, determine the absolute timing of pivotal events in lunar geologic history, and reveal the geological diversity of the differentiated lunar body.
... In this context, it is interesting to note that C and N are abundant in carbonaceous chondrite (CC) meteorites sourced from asteroid parent bodies (e. g., Sephton, 2002;Pearson et al., 2006). Because asteroids with CC-like compositions will have impacted the lunar surface over geological time (e.g., Joy et al., 2012Joy et al., , 2016Joy et al., , 2020, these could be a useful source of these key elements on the Moon (a suggestion first made, to the authors' knowledge, in the science fiction novel Worlds by Haldeman, 1981). In this context, it is noteworthy that Yang et al. (2022) have identified what they interpret to be surviving metre-scale remnants of CC impactor material in multi-spectral images of the lunar surface obtained by the Yutu-2 rover at the Chang'e-4 landing site. ...
... Additionally, organic constituents within such projectiles have also been shown to survive (Mimura and Toyama, 2005;Parnell et al., 2010;Meyer et al., 2011;Burchell et al., 2014aBurchell et al., , 2014bBurchell et al., , 2017. Examples of surviving asteroidal material (see Joy et al., 2016) have been found in lunar samples from Apollo 11 (Goldstein et al., 1970), Apollo 12 (Wood et al., 1971;Zolensky et al., 1996;Joy et al., 2020), and Apollo 16 (Jolliff et al., 1993). Fragments of surviving meteoritic material have also been identified in lunar breccias, including a chondritic fragment within lunar meteorite Pecora Escarpment 02007 (Day et al., 2006;Liu et al., 2009;Joy et al., 2012), and younger Apollo 16 regolith breccias (Joy et al., 2012). ...
... This means that for impacted projectile material to survive over long periods of time (i.e., millions or billions of years) after impact, the material must be protected from destructive processes at the surface. Rapid burial by crater and basin ejecta, and/or by mare basalt flows, could potentially provide protection for meteoritic material (e.g., Crawford and Joy, 2014;Joy et al., 2016), but to be useful as a resource it would need to be Table 1 Abundances of C-bearing materials found in a range of CM/CI meteorites (Murchison, Murray and Orgueil) and the average abundances of N-bearing molecules found in CM meteorites (Murchison and Murray) and associated vaporisation temperatures included for both C-and N-bearing molecules (we have assumed that these compounds are homogeneously distributed within the meteorites). [1] Huss and Lewis (1994). ...
... Although small fragments of intact meteoritic materials have been found in the lunar regolith (see Joy et al. 2016 for a review), indicating that partial survival of some impacting bodies does occur, there is a general expectation that the bulk of such material will melt or vaporize on impact (e.g., Melosh 1989). On the other hand, numerical simulations of meteoritic and cometary impacts with the Moon indicate that significant projectile survival may occur if the impact is oblique and/or has a relatively low (≤ 12 km/s) velocity (e.g., Pierazzo and Melosh 2000;Bland et al. 2008;Crawford et al. 2008;Yue et al. 2013;Svetsov and Shuvalov 2015). ...
... It is also true that the scientific and technical infrastructure provided by an outpost of this kind will greatly aid in the utilization of lunar resources and in the prospecting for additional resources. In addition, a lunar outpost could help kick-start a space economy by providing a market for commercial space resource companies while at the same time providing infrastructure to support their activities (e.g., Spudis and Lavoie 2011;Crawford 2016;Metzger 2016;Sowers 2016;Kornuta et al. 2019). For these reasons, strong synergies exist between human missions to the Moon and the utilization of lunar resources that need to be taken into account in the development of future human exploration initiatives (e.g., Neal et al. 2014). ...
... The types of asteroids that are sampled at the present day on Earth as meteorites, or the proportion between cometary bodies and near Earth-cross asteroids, may not necessarily be similar to those that were responsible for the impact basins and craters on the Moon in the basin-forming epoch. Recent review papers on the topic of impactor sources are provided by Walker et al. (2015) and Joy et al. (2016). ...
... Fragments of exogenous contributions to the lunar regolith provide more direct evidence of the types of small bodies striking the Moon at different times (Armstrong et al. 2002;Chapman 2002;Rubin 2012;Joy et al. 2012Joy et al. , 2016Joy et al. , 2020a. The survivability of different types of projectiles on the Moon varies, controlled by such factors as impact velocity, where long and short period comets typically have higher collisional speeds (>20 km/s) compared with those of asteroids (~18 km/s on average). ...
... To date only mm to sub-mm sized meteorite silicate and metal meteorite fragments have been found in lunar regolith samples (Joy et al. 2016) and, given the constraints of what we know of comets from silicate phases collected by the Stardust mission and stratospheric interplanetary dust particles (IDPs), no cometary silicate debris has been directly identified in lunar regolith samples. Our best view to the basin-forming epoch surface regolith record, where such an archive potentially resides, are through the "ancient" regolith breccias formed from soils >3.5 Ga (McKay et al. 1986;Joy et al. 2011). ...
... More optimistically, some projectile material might survive in a solid phase. A standard chemical and isotopic analysis exist for characterizing meteorites and impact melts (Tagle and Hecht, 2006;Joy et al., 2016), which could reveal the ISO's composition. ...
Lunar sulfides and oxides are a significant source of noble and base metals and will be vital for future human colonies’ self-sustainability. Sulfide detection (pyrite and troilite) applies to many technological fields and use cases, for example, as a raw material source (available in situ on the Lunar surface) for new solar panel production methods. Ilmenite is the primary iron and titanium ore on the Moon and can provide helium-3 for nuclear fusion and oxygen for rocket fuel. The most important ore minerals have prominent absorption peaks in a narrow far-infrared (FIR) wavelength range of 20–40 μm, much stronger than the spectral features of other common minerals, including significant silicates, sulfates, and carbonates. Our simulations based on the linear mixing of pyrite with the silicates mentioned above indicated that areas containing at least 10%–20% pyrite could be detected from the orbit in the FIR range. MIRORES, Multiplanetary far-IR ORE Spectrometer, proposed here, would operate with a resolution down to <5 m, enabling the detection of areas covered by 2–3 m² of pyrite (or ilmenite) on a surface of ∼17 m² from an altitude of 50 km, creating possibilities for detecting large and local smaller orebodies along with their stockworks. The use of the Cassegrain optical system achieves this capability. MIRORES will measure radiation in eight narrow bands (0.3 µm in width) that can include up to five bands centered on the ore mineral absorption bands, for example, 24.3, 24.9, 27.6, 34.2, and 38.8 µm for pyrite, marcasite, chalcopyrite, ilmenite, and troilite, respectively. The instrument size is 32 x 32 x 42 cm, and the mass is <10 kg, which fits the standard microsatellite requirements.
... However, in spite of the seeming abundance of meteorite fragments in the lunar regolith and asteroids of the Solar System, their finds are extremely scarce. The exception is small fragments of Fe-Ni metal of supposedly meteorite origin, which are present in the lunar and HED breccias, and scarce finds of both chondritic and achondritic material (Lorenz et al., 2007;Joy et al., 2016;Demidova et al., 2022). The scarcity of such finds is related to the fragmentation, melting, and to lesser extent, evaporation of both impactor and target material during numerous impact events, which could lead to the efficient stirring of material. ...
... The Moon will provide future in situ resource utilisation (ISRU) missions with a valuable feedstock in form of its powdered surface layer of soil-the lunar regolith. This material is formed from a mixture of lunar rock and minerals with an added exogenically component introduced by various mechanisms: solar wind particles [35], asteroidal material, and cometary material [24,27,37]. The regolith, thus, contains a diverse range of chemical elements, which may be valuable reserves for a range of industrial and exploration applications [6,11]. ...
... The regolith, thus, contains a diverse range of chemical elements, which may be valuable reserves for a range of industrial and exploration applications [6,11]. Therefore, access and extraction of the regolith are widely regarded as a key enabler of a future lunar economy and permanent human presence [11,19,34,41,42,46], which will also enable a wide range of lunar science applications [10,14,16,17,26,27]. ...
Future in situ resource utilisation (ISRU) lunar mission concepts will require mechanisms that allow the available feedstock–mainly the lunar regolith–to be extracted from the lunar surface. Such extraction techniques in the reduced gravity environment of the Moon will need to minimise excavation forces, due to mass restrictions for robotic landers/vehicles and the large financial implications of placing cargo onto Earth’s satellite. An investigation of necessary excavation forces, both horizontally as well as vertically, for small-scale continuous lunar excavation systems based on their geometric inlet shapes, cutting angles, and digging depths has been undertaken. The use of vibration to disaggregate lunar soil and to reduce the necessary forces is explored as a proof-of-concept. Tests performed in a large analogue testbed have shown that the optimisation of the cutting geometry is crucial, as it inherently influences the necessary forces or even prevents deeper cuts into the soil. Our experiments indicate that shallow cuts (low digging depth) into soil at shallow angles are beneficial, and that the piling up of large surcharge masses must be avoided. Critically, applying vibration to cutting edges seems highly beneficial, as the achievable force reductions of up to 50% in the tested conditions far outweigh the additional power requirements. To make these implications immediately applicable to a wider audience, an estimation of available traction forces for certain robotic vehicles based on their mass is added for comparison.
... However, in spite of the seeming abundance of meteorite fragments in the lunar regolith and asteroids of the Solar System, their finds are extremely scarce. The exception is small fragments of Fe-Ni metal of supposedly meteorite origin, which are present in the lunar and HED breccias, and scarce finds of both chondritic and achondritic material (Lorenz et al., 2007;Joy et al., 2016;Demidova et al., 2022). The scarcity of such finds is related to the fragmentation, melting, and to lesser extent, evaporation of both impactor and target material during numerous impact events, which could lead to the efficient stirring of material. ...
The formation of basalts is a global stage in the evolution of differentiated cosmic body (planet or asteroid) of the Solar System. The paper presents the main chemical and mineralogical features of basaltic meteorites of the SNC, HED group, angrites and lunar mare basalts based on literature data. Despite the differences in the products of basaltic volcanism on different cosmic bodies and significant compositional variations in major minerals of basaltic rocks, most of them belong to low-alkaline basalts, suggesting the prevalence of this type of rocks at least among small bodies of the Solar System. All of them are characterized by the presence of such rock-forming minerals as pyroxene, olivine, and plagioclase, and their spectral characteristics can be used to search for basalts on exoplanets. The main factors affecting the spectral characteristics of atmosphere-free bodies and larger planets with an atmosphere are shown, and the possibility of searching for products of basalt volcanism on exoplanets during future missions is considered.
... Age populations of impact glasses in the Chang'e-5 soil defined by U-Pb isotopic compositions, combined with CSFD model ages of individual craters and model probabilities of glass delivery from different craters to the landing site, suggest discrete episodes of impact cratering that varied over relatively short time scales. If this is correct, it implies that the age-frequency distributions of lunar impacts might provide information about dynamical events and processes that deliver impactors to the inner solar system (41,42). ...
Impact glasses found in lunar soils provide a possible window into the impact history of the inner solar system. However, their use for precise reconstruction of this history is limited by an incomplete understanding of the physical mechanisms responsible for their origin and distribution and possible relationships to local and regional geology. Here, we report U-Pb isotopic dates and chemical compositions of impact glasses from the Chang'e-5 soil and quantitative models of impact melt formation and ejection that account for the compositions of these glasses. The predominantly local provenance indicated by their compositions, which constrains transport distances to <~150 kilometers, and the age-frequency distribution are consistent with formation mainly in impact craters 1 to 5 kilometers in diameter. Based on geological mapping and impact cratering theory, we tentatively identify specific craters on the basaltic unit sampled by Chang'e-5 that may have produced these glasses and compare their ages with the impact record of the asteroid belt.
... More optimistically, some projectile material might survive in solid phase. A suite of standard chemical and isotopic analyses exists for characterizing meteorites and impact melts (Tagle & Hecht 2006;Joy et al. 2016), which could reveal the ISO's composition. ...
... If ISO craters can be identified, then surviving ISO meteorites in and around the crater could be readily analyzed for metallic content, oxygen isotope fractionation, and elemental ratios (e.g., Fe/Mn; Joy et al. 2016); however, if ISOs are composed of highly volatile, exotic ice (Seligman & Laughlin 2020;Desch & Jackson 2021), we may expect that they undergo near-complete vaporization upon impact and suffer the same issues in chemicalbased identification as comets do (Tagle & Hecht 2006; a small percentage of water content may survive comet impacts ;Svetsov & Shuvalov 2015). An ISO's composition could still be investigated if its material persists in the impact melt or vapor condensates. ...
The discoveries of two interstellar objects (ISOs) in recent years have generated significant interest in constraining their physical properties and the mechanisms behind their formation. However, their ephemeral passages through our solar system permitted only incomplete characterization. We investigate avenues for identifying craters that may have been produced by ISOs impacting terrestrial solar system bodies, with particular attention toward the Moon. A distinctive feature of ISOs is their relatively high encounter velocity compared to asteroids and comets. Local stellar kinematics indicate that terrestrial solar system bodies should have experienced of order unity ISO impacts exceeding 100 km s ⁻¹ . By running hydrodynamical simulations for projectiles of different masses and impact velocities up to 100 km s ⁻¹ , we show how late-stage equivalence dictates that transient crater dimensions alone are insufficient for inferring the projectile’s velocity. On the other hand, the melt volume within craters of a fixed diameter may be a potential route for identifying ISO craters, as faster impacts produce more melt. This method requires that the melt volume scales with the energy of the projectile while the crater diameter scales with the point-source limit (subenergy). Given that there are probably only a few ISO craters in the solar system at best, and that transient crater dimensions are not a distinguishing feature for impact velocities, at least up to 100 km s ⁻¹ , identification of an ISO crater proves a challenging task. Melt volume and high-pressure petrology may be diagnostic features once large volumes of material can be analyzed in situ.
