Mare Nectaris

It appears to me that Mare Nectaris is overspill and run off from Mare Tranquillitatis. The visual appearance is of an alluvial fan as material was deposited into the basin, known as Sinus Asperitatis . I imagine numerous craters were lost as the Nectaris basin filled with lava, In fact you can just make one out to the east of the 28Km Medler (sat in the mouth of the basin). A ghost crater called Daguerrre.

 

A wealth of other interesting features surround this 333km basin. To it's east are a number of craters dedicated to the navigators of the sea such as Columbo ,Cook, Magelhaens. Moving to the south west is the part sunken and pockmarked Fracastorius. Finally and to the west is a popular target for astrophotographers the triple crater feature of the high walled Theophilus, Cyrillus & Catharina.

For me a wonderful area to explore.