Properties of novel LX lunar regolith simulant system — the base simulants: Part 2

Abstract

Sustainable and fast exploration and colonisation of our solar system are only possible if humans learn to use the resources of other celestial bodies, such as our Moon, to build settlements and infrastructure, extract valuable materials for the production of secondary goods and obtain consumables such as water and oxygen for life support and as fuel. The most abundant resource on the Moon is the lunar regolith, a layer of loose pulverised rock material covering the Moons surface many meters thick. So-called ISRU (in-situ resource utilisation) technologies are being developed to make use of this material. To develop and test such technologies on Earth, analogue materials (simulants) are essential. In a previous study, the LX lunar regolith simulant system was developed for this purpose, and the base simulants LX-T100 and LX-M100 were characterised regarding their mineralogy and chemistry, particle size distribution, particle morphology, density, void ratio and porosity. This study presents the second part of a comprehensive characterisation of the base simulants, aimed at providing detailed insights into their adsorption behaviour and specific surface area, compressibility, flow properties, magnetic properties and optical properties. Using the Brunauer–Emmett–Teller (BET) method, the specific surface area was precisely quantified, being, for example, relevant to the adhesion and reactivity of lunar dust. Compressibility was measured using an oedometer test, providing insight into the settlement behaviour of the simulants under load. Flow properties were assessed through a series of dynamic and static tests, including angle of repose, Hausner ratio, rheometry and direct shear measurements, to determine the simulant’s handling and transportation behaviour. The magnetic properties were characterised to understand the magnetic susceptibility and remanence, which are crucial for dust mitigation strategies and electromagnetic interference assessments. Spectral reflectance was evaluated using spectrophotometry across relevant wavelengths, providing useful data for remote sensing calibration and surface composition analysis. It was shown that the simulants are good analogues for simulating adsorption, compression, and flow behaviour. However, their ability to represent magnetic and optical properties remains limited. The results from these investigations contribute to a more thorough understanding of the LX base simulants, enhancing their fidelity for scientific research.