Damaged circular formation.
Steep slopes riddled supporting crater Blancanus to the South-West.
Very high walls ridden by Porter to the North-East Rutherford
to the South-East Clavius K to the South-West and Clavius L to
Large flat floor with Clavius D C N J & JA on an arc of circle.
Numerous craterlets whose a chain to the South-West. Lines of
Dimension: 231x231Km / 136x136Mi
Height/Wide ratio: 0.0204
Interest : Exceptional formation
Observation period: 1 day after First Quarter or Last Quarter
Minimal Instrument: 10x binoculars