  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.
