Elmer is a 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...

 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 is located to the south of Mare Smythii

Mare Smythii

Mare Smythii is a lunar mare located along the equator on the easternmost edge of the lunar near side. The Smythii basin where the mare is located is of the Pre-Nectarian epoch, while the surrounding features are of the Nectarian system...

, near the eastern limb 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...

. This crater is seen at a highly oblique angle from Earth

Earth

Earth is the third planet from the Sun, and the densest and fifth-largest of the eight planets in the Solar System. It is also the largest of the Solar System's four terrestrial planets...

, and the visibility is affected by libration

Libration

In astronomy, libration is an oscillating motion of orbiting bodies relative to each other, notably including the motion of the Moon relative to Earth, or of Trojan asteroids relative to planets.-Lunar libration:...

. Elmer lies southwest of the crater Kreiken

Kreiken (crater)

Kreiken is a small lunar crater that is located near the eastern limb of the Moon. It lies to the south of the crater Kiess and the Mare Smythii. Just to the south-southwest is the smaller crater Elmer, and to the west is Dale....

, and east-southeast of the larger Dale

Dale (crater)

Dale is a small lunar crater located in the far eastern part of the Moon's near side, to the south of the Mare Smythii. It lies to the southeast of the larger crater Kastner and northeast of Ansgarius...

. This is a circular, bowl-shaped crater with an interior floor that occupies about half the total diameter.