A high-resolution global basemap of (101955) Bennu

In early 2019, NASA's OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, and Security–Regolith Explorer) mission surveyed asteroid (101955) Bennu with a collection of instruments, including the OSIRIS-REx Camera Suite (OCAMS) PolyCam imager. Using PolyCam panchromatic images, we constructed a globally controlled basemap of Bennu at an approximate ground sample distance of 5 cm with a mean spatial accuracy of ~30 cm. The basemap was photometrically normalized using a Minneart phase angle correction. New mapping methods were developed to combine images of Bennu's irregular shape and extremely rough surface into a nearly seamless mosaic. Here we present the global basemap of Bennu and discuss the image processing techniques used to construct a high-resolution mosaic of an irregular small body. •We produced a global basemap of asteroid Bennu at a ground sample distance of 5 cm.•New methods were developed to deal with Bennu's rough surface and irregular shape.•Images were rectified to a 3D digital terrain model with a mean facet size of 80 cm.•Images were photometrically normalized to 30° phase angle using a Minneart model.•Overlaps were masked along natural feature boundaries for a nearly seamless result.