Ibn Yunus (Moon)

Named after Abul al-Hasan ben Ahmad Yunus - Egyptian astronomer (950-1009).

Ibn Yunus is the remains of a flooded lunar crater. It lies on the far side , just past the eastern limb. 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. (wikipedia entry)

A crater is a circular depression likely created by an impact event. On the Moon they are named after deceased scientists, polar explorers, astronauts or cosmonauts.