is a
Lunar Crater located near the southeast limb of the
Moon . Because of foreshortening the crater appears oval in shape, although it is actually nearly round. To the northeast is the large
Petavius Crater . South of Snellius is the
Stevinus Crater .
The rim of Snellius is heavily worn and eroded, with overlapping craterlets. The floor is somewhat irregular and uneven. The western rim marks the start of the
Vallis Snellius , one of the longest valleys on the
Moon . It continues nearly 500
Kilometer s to the northwest to near the edge of
Mare Nectaris . Its origin is most likely associated with the formation of the
Lunar Mare .
Just to the northwest is 'Snellius A', a crater with a notable
Ray System that overlaps ths southwest reaches of
Mare Fecunditatis to the north.
By convention these features are identified on lunar maps by placing the letter on the side of the crater mid-point that is closest to Snellius crater.
