Transitions in Rubble-pile Asteroid Chaotic Environment and granular Structures

Introduction

We are now living in exciting times for asteroid exploration. The increasing availability of in-situ observation data, providing an unprecedented level of detail, makes the study of asteroids an exciting and living frontier.

Nature of Asteroids

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.

Challenges in Understanding Asteroids

Not only is the understanding of asteroids’ properties limited by a lack of data, but it is also 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 Methodology

TRACES enables a new paradigm for the characterization of granular systems in asteroid-related scenarios. The ambition is to demonstrate that the macroscopic behavior of granular media in asteroid environments can be inferred from local properties of the grain.

Foundation of the Methodology

The methodology lays its foundation on:

1. A cutting-edge simulation tool, able to resolve the dynamics of grains to particle-scale precision.
2. A theoretical framework, able to decode the chaotic nature of particle-scale dynamics.

Validation of Hypothesis

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:

1. Proof-of-concept.
2. Laboratory scenarios involving experiments in vacuum/low-g.
3. Full-scale scenarios involving asteroid mission data.

Potential Impact

If successful, TRACES will enable the characterization of surface and internal properties of asteroids with limited observation data. This will play a crucial role in enabling the next breakthrough in asteroid science, as well as the efficient and cost-effective design of the next generation of space missions to explore and exploit asteroids, including planetary defense applications.