Morphological mapping is a fundamental step in studying the processes that shaped an asteroid surface. Yet, it is challenging and often requires multiple independent assessments by trained experts. Here, we present fast methods to detect and characterize meaningful terrains from the topographic roughness: entropy of information, and local mean surface orientation. We apply our techniques to Didymos and Dimorphos, the target asteroids of NASA's DART mission: first attempt to deflect an asteroid. Our methods reliably identify morphological units at multiple scales. The comparative study reveals various terrain types, signatures of processes that transformed Didymos and Dimorphos. Didymos shows the most heterogeneity and morphology that indicate recent resurfacing events. Dimorphos is comparatively rougher than Didymos, which may result from the formation process of the binary pair and past interaction between the two bodies. Our methods can be readily applied to other bodies and data sets.
@article{arxiv.2405.19764,
title = {Macro-scale roughness reveals the complex history of asteroids Didymos and Dimorphos},
author = {Jean-Baptiste Vincent and Erik Asphaug and Olivier Barnouin and Joel Beccarelli and Paula G. Benavidez and Adriano Campo-Bagatin and Nancy L. Chabot and Carolyn M. Ernst and Pedro H. Hasselmann and Masatoshi Hirabayashi and Simone Ieva and Ozgur Karatekin and Tomas Kasparek and Tomas Kohout and Zhong-Yi Lin and Alice Lucchetti and Patrick Michel and Naomi Murdoch and Maurizio Pajola and Laura M. Parro and Sabina D. Raducan and Jessica Sunshine and Gonzalo Tancredi and Josep M. Trigo-Rodriguez and Angelo Zinzi},
journal= {arXiv preprint arXiv:2405.19764},
year = {2024}
}