Disk-resolved photometric modeling and properties of asteroid (101955) Bennu

© 2020 The Authors OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, and Security–Regolith Explorer) is a NASA mission to return a sample of asteroid (101955) Bennu. Photometric modeling of Bennu\u27s surface is a key element of both sample site characterization and our broader scientific understanding of the asteroid. Bennu\u27s heterogeneous surface presents substantial variation in reflectance and produces a scattered dataset that poses a challenge to photometric modeling. We show that the resolution of the shape model with which we calculate photometric angles strongly affects the accuracy of the analysis, as well as the efficacy of subsequent photometric corrections. We use global imaging data to fit empirical photometric models of the surface. These models represent the average behavior of Bennu\u27s surface and can be used beyond this work to photometrically correct panchromatic and color basemaps of Bennu and perform albedo analyses of individual features on Bennu\u27s surface. Bennu\u27s global photometry reveals a moderate opposition effect and detectable phase reddening, both of which suggest a macroscopically rough surface, which is confirmed by centimeter-scale images of the asteroid