Situated on the edge of Mare Crisium, the crater Proclus is the brightest object in this image.
Proclus is a relatively young crater, roughly pentagonal in shape. The crater's ray system extends for almost 600 km, but it clearly shows asymetry with a blank area to the southwest, which suggests that the object that created the crater impacted at an oblique angle. The craters Yerkes and Lick are also visible, but they can been seen more clearly when nearer to the terminator.
This zoomed-in image shows the pentagonal shape of the crater (to me, it looks more like a hexagon!):