Hume 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 lies along 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...

, along the southeast edge 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...

. It is located just on the far side of the Moon, but it is often brought into sight 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...

 due to 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:...

. Hume lies just to the west-northwest of the much larger Hirayama

Hirayama (crater)

Hirayama is a large lunar crater that is located on the far side of the Moon, just beyond the eastern limb. This region of the surface is sometimes brought into view from Earth during periods of favourable libration. However it is best viewed from orbit. This crater is located along the...

, and to the northeast of the flooded crater Swasey

Swasey (crater)

Swasey is a small lunar crater that lies along the eastern limb of the Moon. It lies near the southeastern edge of the Mare Smythii, to the west of the walled plain Hirayama...

.

Hume has been flooded by flows of basalt

Basalt

Basalt is a common extrusive volcanic rock. It is usually grey to black and fine-grained due to rapid cooling of lava at the surface of a planet. It may be porphyritic containing larger crystals in a fine matrix, or vesicular, or frothy scoria. Unweathered basalt is black or grey...

ic 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...

, leaving only a slender rim projecting above the surface. Its interior floor is level and has the same 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...

 as the 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...

 to the northwest. The rim has a wide gap at the northern end, and the floor lies open to the exterior. This feature is not marked by any overlying impacts of note.

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 Hume.

Hume	Latitude	Longitude	Diameter
A	3.8° S	90.6° E	25 km
Z	3.6° S	90.4° E	14 km

External links

• LTO-82A4 Hirayama — L&PI topographic map
  Topographic map
  A topographic map is a type of map characterized by large-scale detail and quantitative representation of relief, usually using contour lines in modern mapping, but historically using a variety of methods. Traditional definitions require a topographic map to show both natural and man-made features...