Manilius 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...

 impact 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...

 on the northeast edge of Mare Vaporum

Mare Vaporum

Mare Vaporum is a lunar mare located between the southwest rim of Mare Serenitatis and the southeast rim of Mare Imbrium. The lunar material surrounding the mare is from the Lower Imbrian epoch, and the mare material is from the Eratosthenian epoch. The mare lies in an old basin or crater that is...

. It has a well-defined rim with a sloping inner surface that runs directly down to the ring-shaped mound of scree

Scree

Scree, also called talus, is a term given to an accumulation of broken rock fragments at the base of crags, mountain cliffs, or valley shoulders. Landforms associated with these materials are sometimes called scree slopes or talus piles...

 along the base, and a small outer rampart. The small crater interior has a higher albedo

Albedo

Albedo , or reflection coefficient, is the diffuse reflectivity or reflecting power of a surface. It is defined as the ratio of reflected radiation from the surface to incident radiation upon it...

 than the surroundings, and it appears bright when the sun is overhead. Within the crater is a central peak formation near the mid-point. The crater also possesses a ray system

Ray system

A ray system comprises radial streaks of fine ejecta thrown out during the formation of an impact crater, looking a bit like many thin spokes coming from the hub of a wheel. The rays can extend for lengths up to several times the diameter of their originating crater, and are often accompanied by...

 that extends for a distance of over 300 kilometers.

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 Manilius.

Manilius	Latitude	Longitude	Diameter
B	16.6° N	7.3° E	6 km
C	12.1° N	10.4° E	7 km
D	13.2° N	7.0° E	5 km
E	18.3° N	6.4° E	49 km
G	15.5° N	9.7° E	5 km
H	17.8° N	8.6° E	3 km
K	11.9° N	11.2° E	3 km
T	13.4° N	10.6° E	4 km
U	13.8° N	10.8° E	4 km
W	13.4° N	12.9° E	4 km
X	14.4° N	13.4° E	3 km
Z	16.4° N	11.7° E	3 km

The following craters have been renamed by the IAU

International Astronomical Union

The International Astronomical Union IAU is a collection of professional astronomers, at the Ph.D. level and beyond, active in professional research and education in astronomy...

.

• Manilius A — See Bowen (crater)
  Bowen (crater)
  Bowen is a small lunar crater that is located to the southwest of the Montes Haemus, on the edge of a small lunar mare named the Lacus Doloris. It is distinguished only by having a relatively flat floor, rather than being bowl-shaped like most small craters. Bowen was previously designated...
  
  .
• Manilius F — See Yangel' (crater)
  Yangel' (crater)
  Yangel is a small lunar impact crater that is located in the irregular terrain to the north of the Mare Vaporum. It is a relatively solitary crater formation, and the nearest larger craters lie more than 100 kilometers distant. To the southeast of Yangel' is the prominent crater Manilius...
  
  .