Location of the lunar crater Fontenelle. | |
Coordinates | 63°24′N18°54′W / 63.4°N 18.9°W Coordinates: 63°24′N18°54′W / 63.4°N 18.9°W |
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Diameter | 38 km |
Depth | 1.8 km |
Colongitude | 19° at sunrise |
Eponym | Bernard Fontenelle |
Fontenelle is a lunar impact crater that is located along the northern edge of Mare Frigoris, in the northern part of the Moon. To the northeast is the remnant of the crater Birmingham. Due to its location, this crater appears oval in shape when observed from the Earth because of foreshortening.
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.
Mare Frigoris is a lunar mare in the far north of the Moon. It is located in the outer rings of the Procellarum basin, just north of Mare Imbrium, and stretches east to north of Mare Serenitatis. It is just north of the dark crater Plato.
The rim of this crater is generally circular, but the edge is irregular and in some locations has a notched appearance. This is particularly true along the southwest and the eastern edges. The rim projects above the surface of the Mare Frigoris, and a wrinkle ridge runs several crater diameters to the southeast from the edge. The western rim is attached to rough terrain to the west and northwest.
A wrinkle ridge is a type of feature commonly found on lunar maria. These features are low, sinuous ridges formed on the mare surface that can extend for up to several hundred kilometers. Wrinkle ridges are tectonic features created when the basaltic lava cooled and contracted. They frequently outline ring structures buried within the mare, follow circular patterns outlining the mare, or intersect protruding peaks. They are sometimes called veins due to their resemblance to the veins that protrude from beneath the skin. These are found near craters.
The interior of Fontenelle has a wrinkled appearance along the northern rim. There is a low, wide central hill at the midpoint, and some rough ground to the west of this rise. Only a few tiny craterlets mark the surface of the floor.
To the south of Fontenelle on the lunar mare is a tiny crater that is surrounded by a blanket of high albedo material. This crater displays a resemblance to Linné on Mare Serenitatis. This feature lies about 15 kilometers north-northwest of Fontenelle G, and lacks a designation.
Albedo is the measure of the diffuse reflection of solar radiation out of the total solar radiation received by an astronomical body. It is dimensionless and measured on a scale from 0 to 1.
Mare Serenitatis is a lunar mare located to the east of Mare Imbrium on the Moon. Its diameter is 674 km (419 mi).
To the east of this crater is an unusual geometric configuration in the surface with an angular shape. This came to be known as "Mädler's Square", after the lunar selenographer Johann Mädler. It is roughly square in shape, but appears lozenge-shaped due to foreshortening. This feature was noted in many early books concerning the Moon.
By convention these features are identified on lunar maps by placing the letter on the side of the crater midpoint that is closest to Fontenelle.
Fontenelle | Latitude | Longitude | Diameter |
---|---|---|---|
A | 67.5° N | 16.1° W | 21 km |
B | 61.9° N | 23.0° W | 14 km |
C | 64.4° N | 27.2° W | 13 km |
D | 62.5° N | 23.4° W | 17 km |
F | 64.4° N | 28.2° W | 11 km |
G | 59.5° N | 18.3° W | 4 km |
H | 64.1° N | 20.1° W | 6 km |
K | 69.6° N | 15.6° W | 7 km |
L | 66.5° N | 16.6° W | 6 km |
M | 63.1° N | 28.8° W | 9 km |
N | 64.0° N | 29.7° W | 8 km |
P | 64.1° N | 17.2° W | 6 km |
R | 64.3° N | 18.8° W | 6 km |
S | 65.3° N | 26.7° W | 7 km |
T | 66.3° N | 25.7° W | 7 km |
X | 60.5° N | 27.8° W | 7 km |
Egede is the remains of a lunar impact crater that has been flooded by lava, leaving only the somewhat polygonal circumference of the rim protruding just above the mare. It was named after Norwegian natural historian Hans Egede. It is located on the southern edge of the Mare Frigoris, to the west of the crater Aristoteles. To the southwest is an arc of low mountains curving between the rims of Aristoteles and Eudoxus. The floor of Egede is flat and nearly featureless, except for a few tiny craterlets, including secondaries from Aristoteles. The surviving rim has a maximum altitude of 0.4 km above the surface.
Endymion is a lunar impact crater that lies near the northeast limb of the Moon. It is located to the east of Mare Frigoris, and north of the Lacus Temporis. To the southwest is the somewhat smaller crater Atlas. Because of its location, Endymion has an oval appearance from foreshortening. Beyond the crater along the lunar limb is the Mare Humboldtianum.
Cardanus is a lunar impact crater that is located in the western part of the Moon, in the western part of the Oceanus Procellarum. Due to its location the crater appears very oval because of foreshortening, and it is viewed almost from the side.
Gärtner is the lava-flooded remnant of a crater in the northeast part of the Moon. It is located on the northern edge of the Mare Frigoris. The southern half of the formation is completely missing, and Gärtner forms a semi-circular basin along the edges of the lunar mare. To the north lies the crater Democritus.
Reiner is a lunar impact crater on the Oceanus Procellarum, in the western part of the Moon. It has a nearly circular rim, but appears oval in shape due to foreshortening. The rim edge is well-defined and has not been eroded by impacts. In the midpoint of the irregular crater floor is a central peak. Outside the rim is a hummocky rampart that extends out across the mare for about half a crater diameter.
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.
Encke is a lunar impact crater that is located on the western edge of the Mare Insularum, to the south-southeast of the crater Kepler. The small crater Kunowsky lies to the east-southeast on the mare.
Ansgarius is a lunar impact crater that is located near the eastern limb of the Moon. When viewed from the Earth, the crater has a highly oval shape due to foreshortening, but the rim is actually nearly circular. To the northwest of Ansgarius is the crater La Pérouse, and south is Behaim.
Archytas is a lunar impact crater that protrudes into the northern edge of Mare Frigoris. To the northwest is the comparably sized crater Timaeus, and the smaller Protagoras lies in the opposite direction to the southeast. Further to the southwest, beyond the opposite edge of the mare, is the dark-floored crater Plato.
Arnold is a lunar impact crater that is located in the north-northeastern part of the visible Moon, near the lunar limb. This location gives the crater a notably oval appearance due to foreshortening, although the formation is actually relatively round. It lies to the northeast of the Mare Frigoris, to the north of the crater Democritus. West of Arnold is the smaller crater Moigno.
Birmingham is the surviving remnant of a lunar impact crater. It is named after the astronomer John Birmingham. The crater is located near the northern limb of the Moon, and so is viewed from the Earth at a low angle.
Democritus is a lunar impact crater that is located on the northern part of the Moon, just to the north of the Mare Frigoris. Just to the south of Democritus is the lava-flooded crater Gärtner, which forms a bay on the mare. Directly to the north is Arnold, another flooded formation.
Pontécoulant is a prominent lunar impact crater that is located in the southeastern part of the Moon. Due to its position, the crater appears foreshortened from the Earth and it is difficult to observe much detail. Nearby craters include Hanno just to the northeast, and the comparably sized Helmholtz due south.
De La Rue is the remnant of a lunar impact crater, or possibly several merged craters, creating a formation sometimes called a walled plain. It lies in the northeastern part of the Moon on the near side, and so appears foreshortened due to its location. This formation lies to the north-northwest of the prominent crater Endymion, just beyond the eastern extreme of Mare Frigoris. The crater Strabo intrudes into the northern part of De La Rue's northern rim, and the smaller Thales is attached to the northwestern part of the wall.
Oenopides is a lunar impact crater that is located near the northwestern limb of the Moon, and so appears foreshortened when viewed from the Earth. This formation lies due south of the prominent crater Pythagoras, and is attached to the southwest rim of Babbage E. The southwest rim of Oenopides is part of the northern edge of Oceanus Procellarum. To the south is Markov.
C. Mayer is a lunar impact crater that is located at the northern edge of the Mare Frigoris, due north of the prominent crater Aristoteles. Also to the south, but only a third as distant, is the smaller crater Sheepshanks. Due east of C. Mayer is the flooded crater Kane.
J. Herschel is large lunar impact crater of the variety termed a walled plain. The crater is named after British astronomer John Herschel. It is located in the northern part of the Moon's surface, and so appears foreshortened when viewed from the Earth. The southeastern rim of J. Herschel forms part of the edge of the Mare Frigoris lunar mare. To the northwest is the crater Anaximander. Bordering the northern rim is a large, unnamed lunar plain. Just to the south is the small crater Horrebow.
South is a large lunar impact crater that is located in the northwest part of the Moon. Most of the southern wall of this crater is joined to the Sinus Roris bay of the Oceanus Procellarum, with the southeast rim facing Mare Frigoris. Attached to the northwest of the formation is the larger walled plain Babbage. Just to the northeast is the crater Robinson, and farther to the northeast is another walled plain, J. Herschel.
Fourier is a lunar impact crater that is located in the southwestern part of the Moon's near side, just to the southeast of the crater Vieta. To the northeast is the Mare Humorum. The rim of this crater is roughly circular, but appears oval when viewed from the Earth due to foreshortening.
Oken is a lunar impact crater near the southeastern limb of the Moon. It is normally visible from the Earth, but is foreshortened and within the region of the surface that is subject to libration. To the south and east of this feature is the broad, uneven Mare Australe, which extends to the far side of the Moon.
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.
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