Fermi (crater)
Encyclopedia
Fermi is a large lunar
crater
of the category named a walled plain. It lies on the far side of the Moon
and can not be viewed from the Earth
. Thus this feature must be viewed from an orbiting spacecraft
.
The most notable aspect of Fermi is that the large and prominent crater Tsiolkovskiy
intrudes into its southeastern rim. Unlike Tsiolkovskiy, however, the interior of Fermi is not covered by dark basalt
ic lava
, and so it is barely distinguishable from the surrounding rugged and battered terrain
. If it were located on the near side of the Moon, however, this would be one of the largest visible craters, with a dimension roughly equal to the crater Humboldt
, lying several hundred kilometers to the west-southwest.
This formation has been significantly eroded and damaged by subsequent impacts, and several notable craters lie across the rim and within the basin. Delporte
is the most notable of these, lying across the northwest rim. Just to the east and inside the northern rim of Fermi is Litke
. The smaller crater Xenophon
is centered across the southern rim. In the southern half of the floor are the craters Diderot
and Babakin
.
The rim, where it survives, is the most intact along the northern half. The southern half of the rim has been nearly obliterated, forming an irregular stretch of ground. The interior floor of Fermi has been modified by the creation of Tsiolkovskiy, with striations in the northeastern floor of Fermi, and parallel ridges along the western rim of Tsiolkovskiy. The remaining sections of the floor is somewhat more level, although pock-marked by myriads of tiny craterlets. The central section of the floor in particular has several clustered crater formations.
s that show portions of Fermi.
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 category named a walled plain. It lies 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...
and can not be 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...
. Thus this feature must be viewed from an orbiting spacecraft
Spacecraft
A spacecraft or spaceship is a craft or machine designed for spaceflight. Spacecraft are used for a variety of purposes, including communications, earth observation, meteorology, navigation, planetary exploration and transportation of humans and cargo....
.
The most notable aspect of Fermi is that the large and prominent crater Tsiolkovskiy
Tsiolkovskiy (crater)
Tsiolkovskiy is a large lunar impact crater that is located on the far side of the Moon. It lies in the southern hemisphere, to the west of the crater Gagarin, and northwest of Milne. Just to the south is Waterman, with Neujmin to the south-southwest. This feature was discovered on photographs sent...
intrudes into its southeastern rim. Unlike Tsiolkovskiy, however, the interior of Fermi is not covered by 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...
, and so it is barely distinguishable from the surrounding rugged and battered terrain
Terrain
Terrain, or land relief, is the vertical and horizontal dimension of land surface. When relief is described underwater, the term bathymetry is used...
. If it were located on the near side of the Moon, however, this would be one of the largest visible craters, with a dimension roughly equal to the crater Humboldt
Humboldt (crater)
Humboldt is a large lunar crater that is located near the eastern limb of the Moon. Due to foreshortening this formation has an extremely oblong appearance. The actual shape of the crater is an irregular circle, with a significant indentation along the southeastern rim where the prominent crater...
, lying several hundred kilometers to the west-southwest.
This formation has been significantly eroded and damaged by subsequent impacts, and several notable craters lie across the rim and within the basin. Delporte
Delporte (crater)
Delporte is a lunar impact crater on the Moon's far side. It overlies part of the northwestern rim of the huge walled plain Fermi, and the crater Litke is nearly attached to the southeastern rim....
is the most notable of these, lying across the northwest rim. Just to the east and inside the northern rim of Fermi is Litke
Litke (crater)
Litke is a lunar crater that lies within the large walled plain Fermi, near the north-northwestern inner rim. Less than one crater diameter to the west-northwest is the slightly larger Delporte...
. The smaller crater Xenophon
Xenophon (crater)
Xenophon is a small lunar crater that lies across the southern rim of the walled plain Fermi, to the west of the crater Tsiolkovskiy. South of Xenophon is Zhiritskiy F, a satellite crater of Zhiritskiy to the south-southwest....
is centered across the southern rim. In the southern half of the floor are the craters Diderot
Diderot (crater)
Diderot is a small lunar impact crater on the far side of the Moon. It lies within the southwestern interior floor of the huge walled plain Fermi, about midway between the basin mid-point and the southwest rim. The crater is saucer-shaped, with smaller craters located just to the northwest and the...
and Babakin
Babakin (lunar crater)
Babakin is a small lunar impact crater that is located in the southern part of the walled basin Fermi on the far side of the Moon. The crater rim is symmetrical, circular and sharp-edged, with only some minor erosion and a slight depression along the northern edge...
.
The rim, where it survives, is the most intact along the northern half. The southern half of the rim has been nearly obliterated, forming an irregular stretch of ground. The interior floor of Fermi has been modified by the creation of Tsiolkovskiy, with striations in the northeastern floor of Fermi, and parallel ridges along the western rim of Tsiolkovskiy. The remaining sections of the floor is somewhat more level, although pock-marked by myriads of tiny craterlets. The central section of the floor in particular has several clustered crater formations.
External links
The following are L&PI topographic mapTopographic map
A topographic map is a type of map characterized by large-scale detail and quantitative representation of relief, usually using contour lines in modern mapping, but historically using a variety of methods. Traditional definitions require a topographic map to show both natural and man-made features...
s that show portions of Fermi.
- LTO-101B1 Litke — northern half
- LTO-101B4 Babakin — southern half