Lacus Solitudinis is a small lunar 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...

 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...

. The selenographic coordinates of the lake are 27.8° S, 104.3° E, and it lies within a diameter of 139 km. It forms an arcing feature with the concave side oriented to the northwest. The eastern edge is relatively continuous, while the west is more irregular and disrupted by small craters.

To the northwest of the northern end is the small crater Bowditch

Bowditch (crater)

Bowditch is a lunar crater that lies on the far side of the Moon, just beyond the eastern limb. It is located on a region of the lunar surface that is brought into view due to libration, but at such times the area is viewed from the edge and so not much detail can be observed...

, a lava

Lava

Lava refers both to molten rock expelled by a volcano during an eruption and the resulting rock after solidification and cooling. This molten rock is formed in the interior of some planets, including Earth, and some of their satellites. When first erupted from a volcanic vent, lava is a liquid at...

-flooded feature although it does not appear directly connected to the Lacus Solitudinis. At the western end of the mare, the eroded crater Titius

Titius (crater)

Titius is a lunar crater that is located on the Moon's far side, beyond the eastern limb. It lies to the west of the Lacus Solitudinis, a small lunar mare...

 lies to the northwest. To the south of this feature is Parkhurst Y, with Parkhurst

Parkhurst (crater)

Parkhurst is a heavily degraded lunar crater to the northeast of the Mare Australe on the far side of the Moon. To the north-northeast of Parkhurst is the crater Scaliger and to the southwest lies the dark-floored Gernsback. The small lunar mare named Lacus Solitudinis lies due north of...

itself lying some distance to the southeast.