Transitions in Rubble-pile Asteroid Chaotic Environment and granular Structures

ongoing

We are now living exciting times for asteroid exploration. The increasing availability of in-situ observation data, providing unprecedented level of detail, makes the study of asteroids an exciting and living frontier. Asteroids are rubble piles, i.e., gravitational aggregates of loosely consolidated material. However, no direct measurements of asteroids’ interior exist and little is known about the mechanisms governing their formation and evolution. Not only limited by a lack of data, the understanding of asteroids’ properties is challenged at a fundamental level by their rubble-pile nature. This makes their dynamics subject to the laws of granular mechanics, one of the major unsolved problems in physics. TRACES enables a new paradigm for the characterization of granular systems in asteroid-related scenarios. The ambition is to demonstrate that the macroscopic behaviour of granular media in asteroid environment can be inferred from local properties of the grain. The methodology lays its foundation on a cutting-edge simulation tool, able to resolve the dynamics of grains to particle-scale precision, and a theoretical framework, able to decode the chaotic nature of particle-scale dynamics. TRACES’ hypothesis is validated through theoretical, numerical and experimental work. The ability of the methodology to characterize and identify transitions between dynamical regimes of granular media, is tested gradually, for increasing levels of realism, ranging between proof-of-concept, laboratory scenarios involving experiments in vacuum/low-g, and full-scale scenarios involving asteroid mission data. If successful, TRACES will enable the characterization of surface and internal properties of asteroids with limited observation data. This will play a crucial role to enable the next breakthrough in asteroid science, as well as efficient/cost-effective design of the next generation of space missions to explore and exploit asteroids, including planetary defence applications.