Chrétien (crater)
Encyclopedia
Chrétien is a lunar
crater
that is located in the southern hemisphere
on the far side of the Moon
from the Earth
. It lies due south of the Mare Ingenii
, one of the few maria
on the Moon's far side. The crater lies in the mid-point between the craters Garavito
to the west-southwest and Oresme
to the east-northeast, both of these being somewhat smaller than Chrétien.
The most notable feature of this crater is the low albedo
interior floor, which has the same darker hue as the Mare Ingenii to the north. The irregular satellite crater Chrétien C, which shares the straight and narrow northeastern rim of Chrétien, is also covered with this dark basalt
ic lava
. The outer rim of Chrétien is irregular in shape, with several other satellite craters intruding into the sides. The most notable of these are Chrétien S across the southwest rim, and Chrétien W attached to the northwest rim.
The northern rim of Chrétien has a break that joins a small, irregular plain. This area has been resurfaced by the same lava flows that covered the interior of Chrétien. At the southern end, the inner wall forms a wide, irregular surface while the damaged rim bulges outward to the south.
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 in the southern hemisphere
Sphere
A sphere is a perfectly round geometrical object in three-dimensional space, such as the shape of a round ball. Like a circle in two dimensions, a perfect sphere is completely symmetrical around its center, with all points on the surface lying the same distance r from the center point...
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...
from the 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...
. It lies due south of the Mare Ingenii
Mare Ingenii
Mare Ingenii is one of the few lunar mare features on the far side of the Moon. The mare sits in the Ingenii basin. This basin material is of the Pre-Nectarian epoch. The mare material located in Ingenii and the surrounding craters is of the Upper Imbrian epoch...
, one of the few maria
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 Moon's far side. The crater lies in the mid-point between the craters Garavito
Garavito (crater)
Garavito is a lunar crater that is located in the southern hemisphere on the Moon's far side. It lies to the north-northwest of the huge walled plain Poincaré, and to the west of the crater Chrétien. It takes its name in honor of the Colombian astronomer Julio Garavito Armero.This crater has a worn...
to the west-southwest and Oresme
Oresme (crater)
Oresme is a crater on the Moon's far side. It lies just to the west-northwest of the larger Von Kármán. To the southwest of Oresme is Chrétien, and to the northwest is the Mare Ingenii...
to the east-northeast, both of these being somewhat smaller than Chrétien.
The most notable feature of this crater is the 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...
interior floor, which has the same darker hue as the Mare Ingenii to the north. The irregular satellite crater Chrétien C, which shares the straight and narrow northeastern rim of Chrétien, is also covered with this dark 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...
. The outer rim of Chrétien is irregular in shape, with several other satellite craters intruding into the sides. The most notable of these are Chrétien S across the southwest rim, and Chrétien W attached to the northwest rim.
The northern rim of Chrétien has a break that joins a small, irregular plain. This area has been resurfaced by the same lava flows that covered the interior of Chrétien. At the southern end, the inner wall forms a wide, irregular surface while the damaged rim bulges outward to the south.
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 Chrétien.| Chrétien | Latitude | Longitude | Diameter |
|---|---|---|---|
| A | 43.9° S | 163.6° E | 13 km |
| C | 44.5° S | 165.3° E | 63 km |
| S | 46.5° S | 160.5° E | 40 km |
| W | 44.3° S | 160.8° E | 34 km |