Ibn Yunus is the remains of a flooded lunar impact crater.

It can only be viewed from Earth under conditions of favorable libration and lighting, and even then it is seen from the edge.

This feature is attached to the east-southeastern outer rim of the flooded crater Goddard.

What survives of this crater is a low, roughly circular ridge projecting up through the mare.

This ring is broken along the western and southern edges, and the interior floor is covered by a nearly level surface with a relatively low albedo.