Seeliger is a relatively small 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...

 that lies near the southeastern edge of Sinus Medii

Sinus Medii

Sinus Medii is a small lunar mare that is located at the intersection of the Moon's equator and prime meridian. As seen from the Earth, this feature is located in the central part of the Moon's near side, and it is the point closest to the Earth...

. This is a circular, cup-shaped feature that has not been appreciably worn by impact erosion.

To the southeast is a 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 the Rima Réaumur, following a line to the northwest. In the north is the 110-km-long Rima Oppolzer, which divides the 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...

where Seeliger is situated from the remainder of the Sinus Medii.

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 Seeliger.

Seeliger	Latitude	Longitude	Diameter
A	1.8° S	3.0° E	4 km
S	2.1° S	2.1° E	4 km
T	2.2° S	4.4° E	4 km