Darwin (lunar crater)
Encyclopedia
Darwin is a lunar
crater
of the type categorised as a walled plain. It lies in the southeastern part of the Moon
, and is sufficiently close to the limb to appear significantly foreshortened when viewed from the Earth
. Attached to its southern rim is Lamarck
. To the northeast is the dark-floored crater Crüger
.
The outer rim of this formation has been significantly disintegrated by the nearby impacts. The southern and northern parts of the rim in particular are all but destroyed. The eastern rim is somewhat worn but intact, and several small craters lie along the southwestern rim. The satellite crater Darwin B, a fairly large formation with a diameter of 56 kilometers, is attached to the outer western rim.
Parts of the interior floor of Darwin have been resurfaced, possibly by lava
or fall-back ejecta, and a system of rille
s cut across the northern part of the floor, crossing the eastern rim and continuing to the southeast. These rilles are designated the Rimae Darwin, and they stretch for a distance of about 280 kilometers. To the east of Darwin, this system of rilles crosses Rima Sirsalis, a wide rille that follows a line to the northeast.
The southern floor of Darwin is only rough level, irregular surface features and several small craterlets. There is an uneven sloping region in the northeast part of the floor, created by ejecta from the Orientale basin
impact that struck the eastern rim. In the western floor is a large, low, somewhat irregular dome
, one of the few such features not found on a mare
. There is also the remnant of a small crater at the southern end of the floor.
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...
of the type categorised as a walled plain. It lies in the southeastern part 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...
, and is sufficiently close to the limb to appear significantly foreshortened when viewed 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...
. Attached to its southern rim is Lamarck
Lamarck (crater)
Lamarck is a crater in the southwestern part of the Moon. The northern portion of the crater is overlain by the walled plain Darwin. To the southeast is Byrgius....
. To the northeast is the dark-floored crater Crüger
Crüger (crater)
Crüger is a lunar crater that is located in the western part of the Moon, to the northeast of the much larger walled plain Darwin.The most distinctive feature about this crater is very dark interior floor that is one of the lowest albedo features on the Moon. The surface has been covered in...
.
The outer rim of this formation has been significantly disintegrated by the nearby impacts. The southern and northern parts of the rim in particular are all but destroyed. The eastern rim is somewhat worn but intact, and several small craters lie along the southwestern rim. The satellite crater Darwin B, a fairly large formation with a diameter of 56 kilometers, is attached to the outer western rim.
Parts of the interior floor of Darwin have been resurfaced, possibly by 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...
or fall-back ejecta, and a system of rille
Rille
Rille is typically used to describe any of the long, narrow depressions in the lunar surface that resemble channels. Typically a rille can be up to several kilometers wide and hundreds of kilometers in length...
s cut across the northern part of the floor, crossing the eastern rim and continuing to the southeast. These rilles are designated the Rimae Darwin, and they stretch for a distance of about 280 kilometers. To the east of Darwin, this system of rilles crosses Rima Sirsalis, a wide rille that follows a line to the northeast.
The southern floor of Darwin is only rough level, irregular surface features and several small craterlets. There is an uneven sloping region in the northeast part of the floor, created by ejecta from the Orientale basin
Mare Orientale
Mare Orientale is one of the most striking large scale lunar features, resembling a target ring bull's-eye. Located on the extreme western edge of the lunar nearside, this impact basin is difficult to see from an Earthbound perspective.Material from this basin was not sampled by the Apollo program...
impact that struck the eastern rim. In the western floor is a large, low, somewhat irregular dome
Lunar dome
A lunar dome is a type of shield volcano that is found on the surface of the Earth's Moon. They are typically formed by highly viscous, possibly silica-rich lava, erupting from localized vents followed by relatively slow cooling. Lunar domes are wide, rounded, circular features with a gentle slope...
, one of the few such features not found on a 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...
. There is also the remnant of a small crater at the southern end of the floor.
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 Darwin.| Darwin | Latitude | Longitude | Diameter |
|---|---|---|---|
| A | 21.8° S | 73.0° W | 24 km |
| B | 19.9° S | 72.2° W | 56 km |
| C | 20.5° S | 71.0° W | 16 km |
| F | 21.0° S | 71.0° W | 18 km |
| G | 21.5° S | 70.7° W | 17 km |
| H | 21.0° S | 68.8° W | 30 km |