Lunar Orbiter 4 image | |
Coordinates | 53°18′S38°48′E / 53.3°S 38.8°E Coordinates: 53°18′S38°48′E / 53.3°S 38.8°E |
---|---|
Diameter | 89 km |
Depth | 3.0 km |
Colongitude | 323° at sunrise |
Eponym | Adriaan Vlacq |
Vlacq is a prominent lunar impact crater that is located in the southeastern part of the Moon, and appears foreshortened when viewed from the Earth. This crater is adjacent to the northeastern rim of the larger Hommel, and to the northwest rim of Rosenberger.
Lunar craters are impact craters on Earth's Moon. The Moon's surface has many craters, almost all of which were formed by impacts.
An impact crater is an approximately circular depression in the surface of a planet, moon, or other solid body in the Solar System or elsewhere, formed by the hypervelocity impact of a smaller body. In contrast to volcanic craters, which result from explosion or internal collapse, impact craters typically have raised rims and floors that are lower in elevation than the surrounding terrain. Impact craters range from small, simple, bowl-shaped depressions to large, complex, multi-ringed impact basins. Meteor Crater is a well-known example of a small impact crater on Earth.
Earth's Moon is an astronomical body that orbits the planet and acts as its only permanent natural satellite. It is the fifth-largest satellite in the Solar System, and the largest among planetary satellites relative to the size of the planet that it orbits. The Moon is, after Jupiter's satellite Io, the second-densest satellite in the Solar System among those whose densities are known.
This crater has become eroded, but not to the degree of the larger neighboring craters. The satellite crater Vlacq G intrudes into the southern rim of Vlacq, and is overlaid in turn along the southwest rim by the sharp-rimmed Vlacq B. The satellite crater Vlacq C is attached to the northeastern exterior rim of Vlacq.
The interior floor of Vlacq has been resurfaced by lava, leaving a nearly level base. The southwest half of the floor, however, is overlaid by ejecta from nearby impacts. In the midpoint of the floor is a rounded massif that is about 15 kilometers in length, being long along the northwest direction. The floor contains a number of tiny craterlets as well as several ghostly crater remnants in the western half. The most notable of these is a circular depression to the west of the central peak.
Lava is molten rock generated by geothermal energy and expelled through fractures in planetary crust or in an eruption, usually at temperatures from 700 to 1,200 °C. The structures resulting from subsequent solidification and cooling are also sometimes described as lava. The molten rock is formed in the interior of some planets, including Earth, and some of their satellites, though such material located below the crust is referred to by other terms.
By convention these features are identified on lunar maps by placing the letter on the side of the crater midpoint that is closest to Vlacq.
Vlacq | Latitude | Longitude | Diameter |
---|---|---|---|
A | 51.2° S | 38.9° E | 17 km |
B | 51.0° S | 39.7° E | 18 km |
C | 50.3° S | 39.4° E | 19 km |
D | 48.7° S | 36.2° E | 34 km |
E | 52.0° S | 36.2° E | 11 km |
G | 54.9° S | 38.1° E | 27 km |
H | 47.9° S | 34.9° E | 11 km |
K | 51.2° S | 36.6° E | 12 km |
Abel is an ancient lunar impact crater that lies near the southeast limb of the Moon's near side. It is located to the south of the crater Barnard, at the northwest edge of the Mare Australe.
Burckhardt is a lunar impact crater that is located in the northeast part of the Moon. It lies between the craters Geminus just to the north and Cleomedes to the south.
Baco is a lunar impact crater that lies in the rugged southern highlands on the near side of the Moon. The rim and inner wall has been eroded and worn by countless minor impacts since the original formation of the crater. As a result, any terraces have been worn smooth and the rim is overlaid by several tiny craterlets. The interior floor is nearly flat, with no characteristic central peak at the midpoint and no small craters of significance.
Hess is a lunar impact crater that lies in the southern hemisphere on the far side of the Moon. The crater rim has been worn by subsequent impacts, leaving a low, eroded outer wall. The flat interior has been resurfaced by lava flows and is free of significant impacts. This floor has a slightly darker albedo than the surrounding terrain.
Biela is a lunar impact crater that is located in the rugged highlands of the southeastern Moon. It is named after Austrian astronomer Wilhelm von Biela. The crater lies to the east of Rosenberger, to the southeast of the Watt–Steinheil double crater.
Brouwer is a large lunar impact crater that is located in the southern hemisphere on the far side of the Moon. Intruding into the western rim of Brouwer is the younger and somewhat smaller crater Langmuir. Further to the east-southeast is the larger walled plain Blackett.
Xenophanes is a lunar impact crater that is located along the northwestern limb of the Moon. It is nearly attached to Volta, a similar formation to the south-southwest. To the northeast is the smaller crater Cleostratus. Xenophanes is significantly foreshortened when viewed from the Earth, hindering observation.
Chebyshev is a large lunar impact crater that lies in the southern hemisphere on the far side of the Moon. The somewhat smaller crater Langmuir is intruding into the east-southeastern rim of Chebyshev, forming a chain of large craters with Brouwer on Langmuir's eastern rim.
Carnot is a large crater in the northern part of the Moon's far side. It intrudes into the southern rim of the huge walled plain Birkhoff. To the west-southwest of Carnot is the crater Paraskevopoulos.
Dyson is a lunar impact crater, 63 kilometers in diameter, that lies on the far side of the Moon, past the northwest limb. It is located in the northern part of the surface, to the northwest of the crater Coulomb, and east of van't Hoff.
Dove is a small lunar impact crater that is located in the rugged lunar highlands in the southeastern part of the Moon. It lies to the north of the prominent crater Pitiscus.
Charlier is a lunar impact crater that is located on the far side of the Moon. To the south-southeast is the larger crater Kovalevskaya, and northeast of Charlier is Perrine.
Curie is a large lunar impact crater, much of which lies on the far side of the Moon as seen from the Earth. The western rim projects into the near side of the Moon, as defined by the selenographic coordinate system. However the visibility of this formation depends on the effects of libration, so that it can be brought fully into view or completely hidden depending on the orientation of the Moon. When visible, however, it is seen nearly from the side, limiting the amount of detail that can be observed.
Kästner is a lunar impact crater that is located near the eastern limb of the Moon, to the southwest of the Mare Smythii. Just to the northwest of Kästner is the walled plain Gilbert. To the south is the prominent crater Ansgarius, and to the southwest lies La Pérouse.
Faye is a heavily eroded lunar impact crater in the rugged southern highlands of the Moon. It is named after French astronomer Hervé Faye. It is attached to the northeastern rim of the crater Delaunay, with Donati located just a few kilometers to the northeast. It forms part of a chain of craters of increasing size to the southwest that continues with La Caille and ends with the walled plain Purbach.
Hagecius is a lunar impact crater in the southeastern part of the Moon's near side. It was named after 16th century Czech naturalist Tadeáš Hájek. This crater forms a triangular formation with the craters Rosenberger to the north-northwest and Nearch to the west-northwest. Like both of these craters, Hagecius has undergone erosion from subsequent impacts, and its outer rim is worn and irregular. The southeastern rim in particular is overlaid by three smaller craters designated Hagecius C, B, and G.
Rosenberger is an old lunar impact crater in the southeastern part of the Moon. It was named after German astronomer Otto August Rosenberger.
Fowler is a large lunar impact crater that lies in the northern hemisphere on the Moon's far side. It lies to the south-southwest of the crater Esnault-Pelterie, and north of Gadomski. Overlying the eastern rim and intruding into the interior is Von Zeipel.
Fridman is the remains of a lunar impact crater on the far side of the Moon. It lies due south of the huge walled plain Hertzsprung, and is attached to the northeastern rim of the crater Ioffe.
Von Békésy is a worn lunar impact crater on the far side of the Moon. It is located in the northern latitudes, behind the northeastern limb of the Moon as seen from the Earth. This is a relatively isolated crater formation, the closest named crater being Volterra, just over one crater diameter to the north-northeast. To the southwest lies Millikan.
Ewen Adair Whitaker was a British-born astronomer who specialized in lunar studies. During World War II he was engaged in quality control for the lead sheathing of hollow cables strung under the English Channel as part of the "Pipe Line Under The Ocean" Project (PLUTO) to supply gasoline to Allied military vehicles in France. After the war, he obtained a position at the Royal Greenwich Observatory working on the UV spectra of stars, but became interested in lunar studies. As a sideline, Whitaker drew and published the first accurate chart of the South Polar area of the Moon in 1954, and served as director of the Lunar Section of the British Astronomical Association.
The National Aeronautics and Space Administration is an independent agency of the United States Federal Government responsible for the civilian space program, as well as aeronautics and aerospace research.
The United States Geological Survey is a scientific agency of the United States government. The scientists of the USGS study the landscape of the United States, its natural resources, and the natural hazards that threaten it. The organization has four major science disciplines, concerning biology, geography, geology, and hydrology. The USGS is a fact-finding research organization with no regulatory responsibility.