The 2MASX J00482185-2507365 occulting pair is a pair of overlapping spiral galaxies found within the vicinity of NGC 253, aka the "Sculptor Galaxy". Both galaxies are more distant than NGC 253. The background galaxy 2MASX J00482185-2507365 is about 800 million light years away from Earth.
This pair of galaxies illuminates the distribution of galactic dust beyond the visible arms of a spiral galaxy. The heretofore unexpected extent of dust beyond the starry limits of the arms shows new areas for extragalactic astronomical study. The dusty arms extend 6 times the radii of the starry arms of the galaxy, and are shown silhouetted in HST images against the central and core sections of the background galaxy.