Regional Photometric Modeling of Asteroid (101955) Bennu

Abstract We present a regional photometric analysis of asteroid (101955) Bennu, using image data from the MapCam color imager OSIRIS-REx Camera Suite (OCAMS). This follows previously reported global which found that Bennu’s roughness was difficult to photometrically model owing unresolved surface variation. Here we find that, even with high-resolution shape (20 cm per facet) and automatic registration (<1 pixel error), Bennu remains challenging model: neither suite empirical models nor physically motivated Hapke were able eliminate scatter in due pixel-scale variations. Nonetheless, improved on by identifying variations response. A linear model, when compared independent measures albedo, revealed correlations between those characteristics phase slope. showed same structure its single-scattering albedo asymmetry factors; although parameters loosely constrained, complicating interpretation their spatial variation, variation relative parameter sensitivity also correlated shallower slope, higher less macroscopic roughness.