Joliot (crater)
Encyclopedia
Joliot 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 lies 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...

, just past the eastern limb. At this location it lies in a region of the surface that comes into sight during a favorable 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:...

, although at such times it is viewed from the side. Thus viewing this crater in detail must be done from orbit
Orbit
In physics, an orbit is the gravitationally curved path of an object around a point in space, for example the orbit of a planet around the center of a star system, such as the Solar System...

.

The crater lies at the northern fringes of the 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 region of the surface associated with Mare Marginis
Mare Marginis
Mare Marginis is a lunar mare that lies on the very edge of the lunar nearside. The selenographic coordinates of this feature are 13.3° N, 86.1° E, and the diameter is 420 km. The name is Latin for "Sea of the Edge"....

 to the south. The crater Lomonosov
Lomonosov (lunar crater)
Lomonosov is a lunar crater that is located just behind the western limb of the Moon. It is almost attached to the east-northeastern outer rim of the larger crater Joliot, and overlies the southern rim of Maxwell...

 is located just to the east-northeast, and Lyapunov
Lyapunov (crater)
Lyapunov is a lunar crater named for Aleksandr Lyapunov that is located along the east-northeastern limb of the Moon, and is viewed from the side by observers on Earth...

 is attached to the western rim. Also attached to the northwest rim, and thus adjacent to Lyapunov, is the crater Rayleigh
Rayleigh (lunar crater)
Rayleigh is a lunar crater that lies along the northeast limb of the Moon. This feature is seen edge-on from Earth, making it difficult to see much detail. In addition, libration effects can completely hide this crater from view. It lies just to the north of Lyapunov, and to the northwest of the...

. Southwest of Joliet is Hubble
Hubble (crater)
Hubble is a lunar crater that lies very near the east-northeastern limb of the Moon. At this location it is viewed almost from the side from Earth, and the visibility of this feature is affected by libration. It lies to the north of the Mare Marginis and northeast of the crater Cannon...

 and farther to the south lies Al-Biruni
Al-Biruni (crater)
Al-Biruni is an impact crater that lies on the far side of the Moon, just beyond the eastern limb. This portion of the surface is sometimes brought into sight due to librations of the Moon, but due to its location the crater is viewed from the side...

.

The outer rim of Joliet is worn and somewhat disintegrated, particularly in the northern and southern sections where the outer wall consists of little more than irregular ridges and craterlets. The rim is somewhar more intact to the east, and particularly so in the west where it has been buttressed by adjacent crater formations.

Within the outer rim, the interior floor has been flooded in the past by 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 a relatively flattened surface that has a lower 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...

 than the surrounding terrain and so appears darker. Parts of the floor have been coated in ray material
Ray system
A ray system comprises radial streaks of fine ejecta thrown out during the formation of an impact crater, looking a bit like many thin spokes coming from the hub of a wheel. The rays can extend for lengths up to several times the diameter of their originating crater, and are often accompanied by...

 from the fresh crater Giordano Bruno
Giordano Bruno (crater)
Giordano Bruno is a 22 km lunar impact crater on the far side of the Moon, just beyond the northeastern limb. At this location it lies in an area that can be viewed during a favorable libration, although at such times the area is viewed from the side and not much detail can be seen...

 to the northeast.

The lava-covered floor contains several ghost-crater
Palimpsest
A palimpsest is a manuscript page from a scroll or book from which the text has been scraped off and which can be used again. The word "palimpsest" comes through Latin palimpsēstus from Ancient Greek παλίμψηστος originally compounded from πάλιν and ψάω literally meaning “scraped...

 remnants, with the largest being an elongated formation to the west of the mid-point. At the mid-point of the floor is a central peak formation.

Named after Frédéric Joliot-Curie
Frédéric Joliot-Curie
Jean Frédéric Joliot-Curie , born Jean Frédéric Joliot, was a French physicist and Nobel laureate.-Early years:...


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 Joliot.

Joliot Latitude Longitude Diameter
P 22.2° N 91.9° E 12 km
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