Named after Leopoldo Nobili - Italian physicist (1784-1835).
Nobili is a lunar crater that lies near the eastern limb , giving it a foreshortened appearance when viewed from the Earth. The crater overlies the western rim of the slightly larger crater Schubert X, and the eastern rim of this satellite crater is overlain in turn by Jenkins, resulting in a triple crater formation. To the south lies Gilbert. Nobili is a circular crater formation with a worn, circular rim. (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.