Rosse 17.9°S, 35.0°E

A young, circular crater, diameter 12 km, lying in the southern area of Mare Nectaris. A bright ray of ejecta from the Tycho impact runs northwards from it (from southwest to northeast). Under high solar illumination, larger instruments show a group (a crater cluster) of very bright tiny secondary craters within the ray. Rosse is the only conspicuous crater on the monotonous lava expanse of the Nectaris Basin and therefore stands out all the more.

Fracastorius 21.5°S, 33.2°E

Fracastorius is a highlight for any aperture of telescope. It is a large complex crater of about 120 km in diameter, that is slightly oval in the north-south direction. Like a bay, the crater wall opens in the north onto the lava surface of Mare Nectaris, in a way that is morphologically similar to the craters Letronne (Mare Humorum) and Le Monnier (Mare Humorum). However, low remnants of the wall are still detectable in the north.

A small, nameless rille crosses the crater floor, almost exactly from west to east, and which splits into a ‘Y’ shape on the eastern side. It crosses the small crater Fracastorius M (4 km). The southern floor of the crater is saturated with a whole host of crater pits, but the northern floor is relatively flat and level. Well to the north is a small crater, surrounded by a bright halo of anorthositic crustal material.