The recent combination of significantly reduced launch costs and the confirmed presence of water ice on the Moon presents new opportunities for lunar construction beyond the constraints of traditional In-Situ Resource Utilization (ISRU). This study investigates an alternative approach that incorporates Earth-supplied cement with lunar-derived resources to manufacture concrete directly on the lunar surface. In this concept, cement is transported from Earth, while lunar rocks are processed into aggregate and water ice is electrolyzed to provide the water and atmosphere necessary for concrete mixing. The resulting precast blocks are assembled into modular arch structures and covered with regolith for thermal and radiation protection. A comparative cost analysis shows that if launch costs fall from current levels (approximately US $1,410/kg) to projected levels under systems like Starship (US $10/kg), transportation costs for materials and equipment to build a habitat for two could drop from around US $138.6 million to just US $0.98 million. This roughly 99% reduction implies that conventional concrete-based construction may become economically viable for early lunar infrastructure. However, further research is needed in key areas such as performance of concrete structure under vacuum condition, in-situ water extraction efficiency, and optimization of regolith covering design.

The exploration of the Moon necessitates sustainable habitat construction. Establishing a permanent base on the Moon requires solutions for challenges such as transportation costs and logistics, driving the emphasis on In-Situ Resource Utilization (ISRU) techniques including Additive Manufacturing. Given the limited availability of regolith on Earth, researchers utilize simulants in laboratory studies to advance technologies essential for future Moon missions. Despite advancements, a comprehensive understanding of the fundamental properties and processing parameters of sintered lunar regolith still needs to be studied, demonstrating the need for further research. Here, we investigated the fundamental properties of lunar regolith simulant material with respect to the stereolithography-based AM process needed for the engineering design of complex items for lunar applications. Material and mechanical characterization of milled and sintered LHS-1 lunar regolith was done. Test specimens, based on ASTM standards, were fabricated from a 70 wt% (48.4 vol %) LHS-1 regolith simulant suspension and sintered up to 1150 degrees C. The compressive, tensile, and flexural strengths were (510.7 +/- 133.8) MPa, (8.0 +/- 0.9) MPa, and (200.3 +/- 49.3) MPa respectively, surpassing values reported in previous studies. These improved mechanical properties are attributed to suspension's powder loading, layer thickness, exposure time, and sintering temperature. A set of regolith physical and mechanical fundamental material properties was built based on laboratory evaluation and prepared for utilization, with the manufacturing of complex-shaped objects demonstrating the technology's capability for engineering design problems.

In-Situ Resource Utilization (ISRU) approaches hold significant importance in plans for space colonization. This work explores a different ISRU concept applying fast-firing, a robust and well-known industrial process, to Mars regolith simulant (MGS-1). The fast-fired specimens were compared to the ones obtained by conventional sintered under low heating rates. When the holding time at the firing temperature is longer than 15 min, fast-fired specimens exhibited higher density and flexural strength (> 35 MPa) than conventional sintering. For both processes, the bulk density values and the mechanical properties of the regolith compacts were enhanced with increasing dwell time. This was attributed to higher heating rates changing the densification/crystallization kinetics involving the basalt glass in the regolith composition. Specifically, high heating rate promotes sintering over crystallization. On these bases, fast firing can be considered a potential candidate for ISRU on Mars.

Icy lunar regolith(ILR) exists in lunar permanently shadowed regions. The preparation of ILR simulant is crucial for conducting ground-based tests for in-situ resource utilization(ISRU). To improve the fidelity of ILR, a novel method for ILR preparation was introduced, termed the water molecule deposition coating(WMDC) method, anchored in the natural formation mechanism of ILR. The cold regolith particles undergo complete tumbling, effectively trapping the water molecules. ILR samples were evaluated for uniformity in water content and micro-morphological characteristics to substantiate the effectiveness of this method. The discrete element method(DEM) was used to analyze the motion and mixing processes of lunar regolith particles within a baffled rotary drum and to determine the impact of various conditions on particle flow behaviors. The results revealed positive correlations between rotation speed, baffle number, and filling degree with central particle density (CPD), with optimal mixing index (MI) achieved at higher rotation speeds and lower filling degrees.

The soil environment has been considered capable of storing toxic substances without serious consequences for the inhabitants since plants are able to bioaccumulate pollutants without compromising their survival. The application of chemicals to increase soil productivity and the dumping of waste have worsened soil quality. Recently, following a greater awareness of the importance of monitoring the damage deriving from the consumption of contaminated crops for humans and of the protection of biodiversity, studies aimed at identifying the effects of soil contamination on terrestrial animals have increased considerably. Studies using field lizards as model organisms fit into this scenario; this research has shed light on the uptake, accumulation, and toxicity of soil pollutants on reptiles. This review summarizes data collected on lizards of the Podarcis genus, a group of resilient wild species capable of living in both pristine and anthropized areas; the data reveal that many of the effects recorded in lizard tissues at the molecular, biochemical, and histological levels are independent of the chemical composition of the contaminants and are mostly linked to the type of cellular response. Overall, these studies confirm Podarcis lizards as a good model system in ecotoxicological and cytotoxicological research, providing an accurate description of the effects of pollutants, clarifying the defense mechanisms activated in relation to different exposure routes and, finally, providing predictive information on the risks faced by other animals. Since the effects recorded in lizards have often also been observed in mammals, it can be concluded that the results obtained from studies on these animals can be translated to other terrestrial vertebrates, including mammals.

This article investigates the use of a bespoke fund, the Space Resources Fund (SRF), to facilitate monetary benefit sharing from commercial space resource utilisation (SRU) and at the same time provide a source of funding for a developing space resource industry. The study investigates the possible objectives such a fund could have and compares these to range of terrestrial fund types that could have similar objectives. We find that there is no one fund type that could meet the possible objectives for a SRF, however, by combining several fund types, it is possible to construct a dedicated fund that meets the objectives initially developed. The study proposes a fund with the Double Bottom Line of both generating monetary benefits from commercial SRU and providing investment capital to an industry targeting SRU. The study also proposes a possible strategy, structure, funding mechanism and benefit distribution mechanism for the SRF and undertakes high level financial modelling to illustrate the wealth creation potential of such a fund. Further, we discuss the advantages and disadvantages of the approach proposed in this study compared to the use of a royalty mechanism for monetary benefit sharing, should monetary benefit sharing ultimately be proposed, by the UN Committee On the Peaceful Uses of Outer Space (COPUOS) for example. This work builds on previous work that reviews the ongoing debate concerning benefit sharing from commercial SRU and explores the use of royalties for such monetary benefit sharing in the context of commercial lunar ice mining. We conclude that a SRF as proposed here could help resolve the long standing dilemma of how to facilitate monetary benefit sharing from commercial SRU without impacting the development of such an industry.

The lunar poles potentially contain vast quantities of water ice. The water ice is of interest due to its capability to answer scientific questions regarding the Solar System's water reservoir and its potential as a useable space resource for the creation of a sustainable cislunar economy. The lunar polar water ice exists in extremely harsh conditions under vacuum at temperatures as low as 40 K. Therefore, finding the most effective technique for extracting this water ice is an important aspect of ascertaining the suitability of lunar water as an economically viable space resource. Based on previous work, this study investigates the impact of the different possible arrangements of icy regolith in the lunar polar environment on the suitability of microwave heating as a water extraction technique. Three arrangements of icy regolith analogues were created: permafrost, fine granular, and coarse granular. The samples were created to a mass of 40 g, using the lunar highlands simulant LHS-1, and a target water content of 5 wt %. The samples were processed in a microwave heating unit using 250 W, 2.45 GHz microwave energy for 60 min. The quantity of water extracted was determined by measuring the sample mass change in real-time during microwave heating and the sample mass before and after heating. The permafrost, fine granular, and coarse granular samples had extraction ratios of 92 %, 83 %, and 97 %, respectively. Possible explanations for the observed variations seen in the mass loss profiles of the respective samples are provided, including explanations for the differences between samples of varying ice morphology (permafrost and granular) and the differences between samples with varying ice surface areas (fine and coarse granular). While differences were observed, microwave heating effectively extracted water in all the samples and remains an effective ISRU technique for extracting water from icy lunar regolith. Differences in the water extraction of different icy regolith could be useful in determining the arrangement of ice in buried samples.

In-Situ Resource Utilisation (ISRU) is increasingly being seen as a viable and essential approach to constructing infrastructure for human habitation on the moon. Transporting materials and resources, from Earth to the Moon, is prohibitively expensive and not sustainable for long-term, large-scale development. Various fabrication technologies have been investigated in recent years, designed for extra-terrestrial exploration and settlement. This review presents a comprehensive study on the development of several sintering techniques of lunar regolith simulant to demonstrate its feasibility for ISRU on the moon. Various critical processing parameters are evaluated in pursuit of creating a structural material that can withstand the extreme lunar environment. Key outcomes are summarised and assessed to provide insight into their viability. Finally, current challenges are addressed and potential improvements, and avenues for further research, suggested.

Permanently Shadowed Regions (PSRs) of the Moon contain rich deposits of water ice. They are very valuable to the space community as in-situ extracted water can be used for many purposes, such as propellant production and human habitat support. PSR craters never see sunlight, therefore solar power is not available there. They also present a cryogenic environment with regolith as cold as 40 K. These challenges can be overcome by employing a Radioisotope Power System (RPS) to provide both thermal and electrical power to resource extraction systems in the PSRs. The work presented here aims at characterizing an ice-mining lunar rover. The rover will be equipped with an Americium-241 (or 241Am) based RPS. 241Am has a 432-year long half-life and can provide decades of stable power output for the rover operations. The innovation lies in the fact that the RPS will not only provide electrical power to the rover, but that its waste heat will be employed to thermally mine ice from its deposits. The rover is equipped with a sublimation plate irradiating the underlying regolith to sublimate ice contained within, and with a cold trap where extracted volatiles will be deposited. This work studied the rover concept feasibility and developed a model of its Thermal Management System (TMS) to meet sublimation plate and cold trap temperature requirements. The results have been validated by a 3D finite element method thermal simulation for icy regolith conditions of 0-10 vol% water-ice content. The findings of this work suggest that it is possible to perform thermal ice-mining in the lunar PSR environment with an RPS-powered rover, with different degrees of efficiencies depending on the amount of ice in the deposits.

The quest for viable construction materials for lunar bases has directed scientific inquiry towards the lunar in-situ resource utilization (ISRU), notably lunar regolith, to synthesize concrete. This study develops an innovative lunar high strength concrete (LHSC) utilizing lunar highlands simulant (LHS-1) and lunar mare simulant (LMS-1) as both precursors and aggregates within the concrete matrix. Mixtures were cured under the conditions simulating the lunar surface temperatures, enabling an evaluation of properties such as flowability, unit weight, compressive strength, modulus of elasticity, and microstructure patterns. Test results indicated that the LMS-1 mixtures exhibited a better flowability and higher unit weight as compared to LHS-1 counterparts. Moreover, the highest 28-day strength was 106.7 MPa and 98.7 MPa for LHS-1 and LMS-1 derived LHSC, respectively. Microstructure analysis revealed that under the identical simulant additions, LHS-1 mixes exhibited superior structural compactness with denser amorphous gels and fewer microcracks. In addition, it possessed a lower Si/ Al ratio and diffraction peak of calcite, along with a greater Ca/Si ratio and hump intensity of amorphous gel phases. The development of this cement-free LHSC, incorporating up to 80 % large-scale lunar materials in the total binder mass, plays a critical role in advancing ISRU on the Moon, thus boosting the viability and sustainability of future lunar construction and habitation while significantly reducing transportation and fabrication costs.