Clementine mosaic | |
Coordinates | 22°00′N135°30′E / 22.0°N 135.5°E Coordinates: 22°00′N135°30′E / 22.0°N 135.5°E |
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Diameter | 61 km |
Depth | Unknown |
Colongitude | 226° at sunrise |
Eponym | Heinrich Siedentopf |
Siedentopf is a worn impact crater on the far side of the Moon. It lies to the east-southeast of the larger crater Vernadskiy. Farther to the south is Hoffmeister.
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.
Vernadskiy is a lunar impact crater on the far side of the Moon, behind the visible eastern limb. It lies to the west-northwest of the smaller crater Siedentopf. To the south is Gavrilov, and much farther to the west is Meggers.
The northwestern section of the crater rim has been damaged, but the remainder of the rim is only moderately worn. The satellite crater Siedentopf Q intrudes into the rim along the southwestern side, and the rampart of this impact covers a portion of the interior floor of Siedentopf. The remainder of the floor is marked by some small craterlets.
By convention these features are identified on lunar maps by placing the letter on the side of the crater midpoint that is closest to Siedentopf.
Siedentopf | Latitude | Longitude | Diameter |
---|---|---|---|
F | 22.1° N | 138.5° E | 42 km |
G | 20.5° N | 138.4° E | 61 km |
H | 20.9° N | 137.2° E | 42 km |
M | 19.0° N | 135.5° E | 31 km |
Q | 20.7° N | 133.7° E | 42 km |
Fracastorius is the lava-flooded remnant of an ancient lunar impact crater located at the southern edge of Mare Nectaris. To the northwest of this formation lies the crater Beaumont, while to the northeast is Rosse.
Eddington is the lava-flooded remnant of a lunar impact crater, located on the western part of Oceanus Procellarum. The western rim is attached to the wall of the walled plain Struve. To the east-southeast is the smaller but prominent crater Seleucus. South of Eddington is Krafft.
Babbage is an ancient lunar impact crater that is located near the northwest limb of the Moon, named after Charles Babbage. It is attached to the southeastern rim of the prominent crater Pythagoras. The crater remnant named South intrudes into the southeastern floor of Babbage.
Fabry is a large lunar impact crater of the form termed a walled plain. It is located on the far side of the Moon, just beyond the northeastern limb. Parts of this area are sometimes brought into view by the effects of libration, but the terrain is seen from the edge and so not much in the way of detail can be observed.
Blanchard is a lunar impact crater that lies on the far side of the Moon, just behind the southwestern limb. It lies to the south-southwest of the crater Arrhenius, and northwest of Pilâtre. Further to the south is the rugged terrain to the north of the walled plain Hausen.
Bolyai is an old lunar impact crater that is located in the southern hemisphere on the far side of the Moon. To the southeast of Bolyai is the crater Eötvös, and to the north is Neujmin. It is named after the 19th century Hungarian mathematician János Bolyai.
Casatus is a lunar impact crater that is located near the southern limb of the Moon. The north-northeast rim of the crater overlies a portion of the slightly larger crater Klaproth. Along the western rim, Casatus A intrudes somewhat into the interior, producing an inward-bowing rim. To the southeast of Casatus is Newton.
Demonax is a lunar impact crater near the southern limb of the Moon. This location makes the crater difficult to observe due to foreshortening. The crater is also illuminated at a very low angle, when it is in the sunlit side. Demonax lies just to the north of the crater Scott, one of the south polar formations. To the north-northwest is Boguslawsky.
Carver is a lunar impact crater that is located on the far side of the Moon, due east of the walled plain Van der Waals. To the northeast is the crater Rosseland, and to the south-southeast lies Kozyrev.
Cannizzaro is a lunar impact crater that is located on the Moon's far side as seen from the Earth, just beyond the northwestern limb. It lies in a region of the surface that is sometimes brought into view due to the effects of libration, but not much detail can be seen since this feature is viewed from the side. The crater lies across the southwestern rim of the much larger-walled plain Poczobutt.
Drebbel is a small lunar impact crater named after Cornelius Drebbel that is located to the northeast of the large walled plain Schickard, in the southwestern part of the Moon. Further to the northeast is the Lacus Excellentiae and the small crater Clausius.
Chernyshev is a lunar impact crater that is located in the northern part of the Moon's far side. It lies to the northeast of the crater Chandler, and to the southeast of the walled plain D'Alembert.
Chandler is a lunar impact crater in the northern hemisphere, on the Moon's far side. It lies to the southeast of the large walled plain D'Alembert, and southeast of the slightly smaller Chernyshev crater.
Congreve is a lunar impact crater that is located on the far side of the Moon relative to the Earth, and lies across the lunar equator. It lies to the west-northwest of the massive walled plain Korolev. To the southeast is the crater Icarus, and due north is Zhukovskiy.
Douglass is a lunar impact crater on the far side of the Moon. It lies to the southwest of the crater Frost and south-southwest of the large walled plain Landau.
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.
Hoffmeister is a lunar impact crater that is located on the Moon's far side, to the northwest of the huge walled plain Mendeleev. Some distance to the north of Hoffmeister lies the crater Siedentopf, and to the west-northwest is Gavrilov.
Pauli is a lunar impact crater that is located on the Moon's far side. It lies about halfway between the lunar equator and southern pole, across the southern rim of the larger walled plain Roche.
Milankovič is a lunar impact crater that is located in the high northern latitudes on the far side of the Moon. Overlapping the southeastern rim is the smaller but more sharply defined crater Ricco. Just to the south is Karpinskiy, and to the north is the prominent Plaskett.
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.