Granular Morphology and Mineralogical Composition for Modeling Lunar Dust Behavior

The need for understanding lunar regolith characteristics is rapidly increasing as NASA prepares to create a long-term human presence on the Moon by the late 2020s. The characteristics of regolith affect not only human and rover mobility on the surface of the Moon, but also in situ resource utilization (ISRU) efforts such as resource processing, resource excavation, and in situ construction/additive manufacturing. Understanding the regolith is vital for lunar exploration, and emerging research is improving the body of knowledge that has long been poorly understood. Therefore, this research will seek to better understand the physical properties of lunar regolith. This will be done by analyzing multiple Apollo lunar regolith and lunar regolith simulant samples to acquire highly accurate morphological, chemical, and mineralogical properties of each sample. These data, and in turn the knowledge it will convey, will help inform applied methods for advancing NASA objectives in their mission to the Moon and on to Mars. X-ray microtomography (XCT) will be used to obtain 3D shapes and sizes of thousands of lunar regolith and simulant particles. These data, along with mineralogical and compositional information through scanning electron microscopy (SEM) and X-ray diffraction (XRD), will be used to create virtual lunar regolith samples for free use by the scientific community. The final product will be a curated, expandable data repository of physical properties of both lunar regolith and regolith simulants. The data repository will provide the basis for high-accuracy calculations of optical properties, optical scattering characteristics, dielectric polarizability, maximum packing fractions, and other physical and geotechnical properties that depend on the shape and size distribution of the regolith. It will also provide a means of determining how well a given regolith simulant imitates the properties of the lunar regolith to which it corresponds. This work is vital to ensuring that Earth-based regolith simulants are accurate enough to test for lunar applications and prepare for data-informed methods for applied lunar engineering, mining, and construction.