Langevin is a 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 far side of the Moon

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...

. It is located to the east of the walled plain Campbell

Campbell (lunar crater)

Campbell is a large lunar crater that is located in the northern hemisphere on the far side of the Moon. It lies to the southwest of the walled plain D'Alembert, an even larger formation. If Campbell were located on the near side of the Moon as seen from the Earth, it would form one of the largest...

, and to the west of the crater Chandler

Chandler (crater)

Chandler is a lunar crater that is located in the northern hemisphere, on the Moon's far side. It lies to the southeast of the large walled plain D'Alembert, and southeast of the slightly smaller crater Chernyshev....

.

This is a heavily damaged crater that has been worn and battered by multiple overlapping impacts. Apart from the depression Langevin creates in the surface, it is scarcely distinguishable from the surrounding terrain. The outer rim and interior features have lost much of their original definition due to this wear. Multiple small craters lie along the rim, including a cluster along the southwest and a crater along the northeast rim. The interior is pock-marked by many small craterlets.

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 Langevin.

Langevin	Latitude	Longitude	Diameter
C	46.4° N	165.5° E	19 km