This OSIRIS narrow-angle camera image focuses on the boundary between the smooth Anubis region (bottom/bottom right) and the rugged Seth region on Comet 67P/Churyumov–Gerasimenko’s large lobe. Parts of the comet’s small lobe can be seen in the background.
The image was taken on 2 September from a distance of around 50 km to the surface of the comet.
For more information, see the blog: Getting to know Rosetta’s comet: boundary conditions