Experimental investigations of impact processes on the metal asteroid 16 Psyche

Metal asteroids are a topic of increasing interest within both the public and private space sectors, as the in-situ resource utilization (ISRU) and asteroid mining communities continue to develop and expand. The metal asteroid 16 Psyche is the largest known M-class asteroid in the main asteroid belt and thus can be considered a prime target for further investigation, with upcoming activities including the NASA Psyche mission which is due to arrive in 2029.Despite this heightened level of interest, many fundamental unknowns remain about 16 Psyche. The limited existing data from ground-based telescopes has resulted in an estimated composition of 30-60% metal (predominantly iron and nickel) and the remaining material as silicate rock. However, both the physical properties —including detailed composition, grain size, material compaction— and behaviours —for instance, response to micrometeorite impacts and ion irradiation— of the surface material remain unknown.This research, conducted at ESA’s Vulcan Analogue Sample Facility, aims to better understand the impact processes on 16 Psyche and their influence on the presence (or lack thereof) of a surface regolith. Hyper velocity impact experiments will be conducted using the two-stage gas gun at the University of Kent. Small copper projectiles (~2mm) will be fired at a metal meteorite to determine if the large metal crystals present will shatter and be comminuted —thus contributing to a metal rich surface regolith—, or if they will instead melt and remain coherent —therefore not significantly contributing to a surface regolith.In doing so, we aim to predict the composition and physical structure of 16 Psyche’s surface material. Drawing on previous hypervelocity experiments, we hypothesize that upon impact the crystals will shatter and produce a loose regolith-like material. If this is the case, there are likely to be positive implications for future asteroid mining activities due to the ease of metal extraction from regolith compared to impact-melt crusts.An estimation of this surface material will enable further, more complex surface research of 16 Psyche, and most importantly for the Vulcan Facility, underpin the development and production of surface simulants of the asteroid. It may also contribute to derisking any future landers, as well as improving the understanding of its utilization potential for resource extraction on Psyche and other metal asteroids. Beyond this, we hope our research can help inform a deeper understanding of the processes of formation and weathering of metal asteroids.