Capuanus is a lunar

Moon

The Moon is Earth's only known natural satellite,There are a number of near-Earth asteroids including 3753 Cruithne that are co-orbital with Earth: their orbits bring them close to Earth for periods of time but then alter in the long term . These are quasi-satellites and not true moons. For more...

 crater

Impact crater

In the broadest sense, the term impact crater can be applied to any depression, natural or manmade, resulting from the high velocity impact of a projectile with a larger body...

 that lies along the southern edge of the Palus Epidemiarum

Palus Epidemiarum

Palus Epidemiarum is a small lunar mare in the southwestern part of the Moon's near side. It lies to the southwest of Mare Nubium, and southeast of Mare Humorum...

. The outer rim is eroded and indented by lesser crater impacts, with notches in the north, west, and southern parts of the rim. The interior floor has been resurfaced by basalt

Basalt

Basalt is a common extrusive volcanic rock. It is usually grey to black and fine-grained due to rapid cooling of lava at the surface of a planet. It may be porphyritic containing larger crystals in a fine matrix, or vesicular, or frothy scoria. Unweathered basalt is black or grey...

ic lava

Lava

Lava refers both to molten rock expelled by a volcano during an eruption and the resulting rock after solidification and cooling. This molten rock is formed in the interior of some planets, including Earth, and some of their satellites. When first erupted from a volcanic vent, lava is a liquid at...

, which is connected to the surrounding lunar mare

Lunar mare

The lunar maria are large, dark, basaltic plains on Earth's Moon, formed by ancient volcanic eruptions. They were dubbed maria, Latin for "seas", by early astronomers who mistook them for actual seas. They are less reflective than the "highlands" as a result of their iron-rich compositions, and...

 by a narrow, crater-formed gap in the northern rim. The floor is particularly notable for the hosting a number of domes

Lunar dome

A lunar dome is a type of shield volcano that is found on the surface of the Earth's Moon. They are typically formed by highly viscous, possibly silica-rich lava, erupting from localized vents followed by relatively slow cooling. Lunar domes are wide, rounded, circular features with a gentle slope...

, which are believed to have formed through volcanic activity.

The rim reaches its maximum altitude along the western face, where it merges with ridges along the edge of the mare. To the northeast the rim dips down very close to the surface, and barely forms a curving ridge in the surface. The southeastern rim is overlaid by a pair of craters.

To the north of Capuanus is the western extreme of the wide rille

Rille

Rille is typically used to describe any of the long, narrow depressions in the lunar surface that resemble channels. Typically a rille can be up to several kilometers wide and hundreds of kilometers in length...

 named Rima Hesiodus, which runs to the east-northeast. To the west-northwest is the crater Ramsden

Ramsden (crater)

Ramsden is a lunar impact crater located on the western stretch of the Palus Epidemiarum. To the east-southeast is the crater Capuanus, and to the north lies Dunthorne....

, and between Capuanus and Ramsden lies a system of intersecting rilles named the Rimae Ramsden.

Satellite craters

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 Capuanus.

Capuanus	Latitude	Longitude	Diameter
A	34.7° S	25.6° W	13 km
B	34.3° S	27.7° W	11 km
C	34.9° S	25.3° W	10 km
D	36.4° S	26.2° W	22 km
E	37.5° S	27.1° W	29 km
F	36.9° S	26.6° W	8 km
H	39.4° S	27.2° W	4 km
K	37.9° S	26.5° W	9 km
L	38.3° S	26.3° W	11 km
M	37.5° S	25.6° W	7 km
P	35.3° S	28.3° W	78 km