Leslie Gertsch

Real-world Mining Feasibility Studies Applied to Asteroids, the Moon and Mars

Recent directives from national leadership in the US have proposed manned exploration and mining on asteroids. While there are dozens of locations in the solar system with potential resources for mining, not all of them are equally promising. A short introduction to the principals of mining feasibility studies can demonstrate that the financial feasibility of mining asteroids is quite questionable regardless of any technical plausibility, especially when compared to other more viable options for mining in space. Furthermore, mineral exploitation beyond Earth can become quite realistic and achievable in only a few years if approached correctly with the appropriate expertise and integration of technology. This paper compares the feasibility of potential mining projects on asteroids, the Earth’s Moon, and Mars based on each location’s dynamic nature. Key components for success, such as location, architecture, and economics are identified and quantified, since each has a significant role in mining feasibility studies that used in the industry.

Asteroid/comet Classification for Mining Purposes

New information about the internal structures of asteroids and comets continues to be obtained. Meanwhile, renewed emphasis on exploration of the Solar System is sharpening the focus on extra-terrestrial raw materials to facilitate the process. The overall energy cost will be reduced significantly by maximizing usage of locally available resources. This paper refines a previously proposed classification of asteroids and comets for mining purposes, based on updated information about their mechanical properties. Class 0, ice composites, appears less homogeneous than before. Class 1, friable rock, may be the largest group, at the expense of Class 0 and especially Class 2, hard rock. Class 3 remains metallic, divided according to the amount of rock present. Additional information is needed for complete classification, so asteroid/comet mining operations can be planned realistically.

Geotechnical Properties of Asteroids Affecting Surface Operations, Mining, and In Situ Resource Utilization Activities

Abstract Geotechnical properties of a granular material affect all surface operations from mobility to landing and excavation. As such, significant efforts to study and model these properties are necessary before sending a spacecraft. Lack of knowledge of regolith material properties adversely affected Apollo, Lunokhod, and Mars Exploration Rover missions; hence additional measures need to be undertaken to prevent potential failures or delays of future missions, in particular missions to explore low-gravity asteroidal surfaces. Geotechnical properties of regolith include cohesion and friction angle, which affect material strength. Friction angle is gravity-dependent, whereas cohesion is not. It is therefore much easier to study and model surface regolith on planetary bodies with significant gravity such as the Moon or Mars. If gravity becomes extremely low, for example, on asteroids, cohesive forces start to dominate. This chapter addresses geotechnical properties of asteroid regolith and their implications for safe mission surface operations. The chapter starts with a high-level overview of soil mechanics followed by an overview of asteroids regolith from past and current missions. Models related to regolith are presented with specific emphasis on sources of cohesion. Several examples of surface operations are given (landing, boulder retrieval, excavation) to illustrate the effect of various properties on the hardware.

Lunar and planetary mining technology

Sustained human life and activities rely on a wide variety of minerals and rocks as fuel and raw mat…

Percussive Penetration of Unconsolidated Granular Media in a Laboratory Setting

This controlled study examined the feasibility of a simple percussive approach to drilling through unconsolidated regolith deposits on Mars. The experiments showed that the approach is feasible at the low power levels and low confining pressures used, and that the rate of impact is more important to the penetration rate than is the mass of the impactor (hammer). More massive impactors tend to lower energy efficiency, as they do in terrestrial pile-driving. Unexpectedly, penetration plotted against applied energy tends to cluster into parallel linear trends. Within a given cluster, penetration is very sensitive to applied energy, while between clusters, the same penetration requires different energy levels. The clusters are separated by gaps whose widths may be related to the average grain size of the material being penetrated. The layered nature of natural sedimentary deposits is reflected in the cumulative energy-penetration plots, which could thus serve to record bedding thickness and frequency during Mars exploration. This study has shown that percussive drilling using a down-the-hole hammer design may be feasible in unconsolidated fine regolith near the ground surface.