Gagarin is a large 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 is located in the southern hemisphere 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...

. To the southwest is the crater Pavlov

Pavlov (crater)

Pavlov is a large lunar crater on the far side of the Moon. Located just to the north-northeast of it is the crater Levi-Civita while to the southeast is Jules Verne....

 and to the northeast lies Keeler

Keeler (lunar crater)

Keeler is a large lunar crater that lies on the Moon's far side. It is connected along the eastern edge to Heaviside, a walled plain of similar dimensions. Keeler, however, is the younger of the two formations, with more clearly delineated features...

. Closer to the rim are the craters Levi-Civita

Levi-Civita (crater)

Levi-Civita is a lunar crater formation that lies on the far side of the Moon. It is located just to the southwest of the large walled plain Gagarin, and nearly as close to the crater Pavlov to the south-southwest. To the northwest of Levi-Civita lies the smaller crater Pirquet.This is an eroded...

 to the southwest, and Beijerinck

Beijerinck (crater)

Beijerinck is a lunar crater on the far side of the Moon. It lies to the south of the larger crater Chaplygin, and to the northeast of the huge walled plain Gagarin....

 to the north-northeast. Isaev

Isaev (crater)

Isaev is a lunar crater on the far side of the Moon. It is entirely contained within the much larger walled plain Gagarin, and lies in the northwestern part of Gagarin's interior floor. The northwestern outer rim of Isaev is attached to the inner rim of Gagarin.Although younger than Gagarin, in...

 lies entirely within the northwest rim of Gagarin. In contrast with the floor of Gagarin, Isaev has a floor with a somewhat low 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...

. Isaev is the largest of six craters falling within the perimeter of Gagarin that have been named after pioneers of Russian aviation and astronautics.

Gagarin has been heavily eroded by a long history of crater impacts. The worn rim forms a low, circular ridge around the somewhat bowl-shaped interior. The inner floor is covered by a multitude of crater impacts of various dimensions. Little if anything remains of a central ridge, if the crater ever possessed such a feature.

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 Gagarin.

Gagarin	Latitude	Longitude	Diameter
G	20.5° S	150.5° E	14 km
M	23.5° S	149.2° E	19 km
T	19.4° S	144.5° E	24 km
Z	15.4° S	149.4° E	29 km