Planck (crater)
Encyclopedia
Planck is a huge lunar
crater
that is located in the southern hemisphere
of the Moon
, on the far side as seen from the Earth
. It lies to the west of the walled plain Poincaré
, another enormous formation only slightly larger than Planck. Both formations are larger than the walled plain Bailly
, the largest crater on the near side. Lying across the southeast rim of Planck is the crater Prandtl
.
Like many lunar formations of this size, the outer rim has been damaged and eroded by lesser impacts, leaving a rugged ring of peaks and ridges that is notched and incised by small craters. The western rim of this walled plain is neatly overlain by a long lunar valley designated the Vallis Planck
. Despite its name, however, this valley is actually radial to the walled plain Schrödinger
to the south. The valley is about 451 kilometers in length.
The most notable feature on the interior floor of Planck is a multi-crater formation in the northern half consisting of Planck W, Planck Y, Planck Z, Planck B, and Planck A. The interior of Planck Y has been almost completely flooded by lava, leaving only a shallow perimeter. Likewise Planck Z has been flooded, although its rim is somewhat more prominent. The interior of Planck B is partly occupied by a concentric crater, and the floor contains several clefts. Parts of the remaining floor of Planck are level and smooth, at least in comparison with the surrounding terrain. This is particularly so in an arc along the northern inner wall. The southern half of the crater is somewhat more irregular, although still forming level plains in places. There are many small craters across the interior of Planck, and a few ghost-crater
remnants.
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...
that is located in the southern hemisphere
Sphere
A sphere is a perfectly round geometrical object in three-dimensional space, such as the shape of a round ball. Like a circle in two dimensions, a perfect sphere is completely symmetrical around its center, with all points on the surface lying the same distance r from the center point...
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...
, on the far side as seen 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...
. It lies to the west of the walled plain Poincaré
Poincaré (crater)
Poincaré is a large lunar impact basin that lies in the southern hemisphere on the far side of the Moon. Most of the formation has been heavily eroded by subsequent impacts, leaving a battered formation with only rugged remnants of the original outer rim to the west.The eastern half has been...
, another enormous formation only slightly larger than Planck. Both formations are larger than the walled plain Bailly
Bailly (crater)
Bailly is a lunar impact crater that is located near the south-west limb of the Moon. The oblique viewing angle gives the crater a foreshortened appearance, and the location near the limb can limit visibility due to libration...
, the largest crater on the near side. Lying across the southeast rim of Planck is the crater Prandtl
Prandtl (crater)
Prandtl is an impact crater on the far side of the Moon. It lies across the southeastern outer rim of the huge walled plain Planck.This crater is roughly circular, but with an outward bulge to the south-southeast. The rim is worn but still retains a well-defined edge...
.
Like many lunar formations of this size, the outer rim has been damaged and eroded by lesser impacts, leaving a rugged ring of peaks and ridges that is notched and incised by small craters. The western rim of this walled plain is neatly overlain by a long lunar valley designated the Vallis Planck
Vallis Planck
Vallis Planck is a long, linear valley located on the far side of the Moon. It is oriented radially to the huge Schrödinger basin, and was most likely formed by that impact...
. Despite its name, however, this valley is actually radial to the walled plain Schrödinger
Schrödinger (crater)
Schrödinger is a huge lunar impact crater of the form traditionally called a walled plain and is named after Erwin Schrödinger. It is located near the south lunar pole on the far side of the Moon, and can only be viewed from orbit. The smaller crater Ganswindt is attached to the southwestern rim of...
to the south. The valley is about 451 kilometers in length.
The most notable feature on the interior floor of Planck is a multi-crater formation in the northern half consisting of Planck W, Planck Y, Planck Z, Planck B, and Planck A. The interior of Planck Y has been almost completely flooded by lava, leaving only a shallow perimeter. Likewise Planck Z has been flooded, although its rim is somewhat more prominent. The interior of Planck B is partly occupied by a concentric crater, and the floor contains several clefts. Parts of the remaining floor of Planck are level and smooth, at least in comparison with the surrounding terrain. This is particularly so in an arc along the northern inner wall. The southern half of the crater is somewhat more irregular, although still forming level plains in places. There are many small craters across the interior of Planck, and a few ghost-crater
Palimpsest
A palimpsest is a manuscript page from a scroll or book from which the text has been scraped off and which can be used again. The word "palimpsest" comes through Latin palimpsēstus from Ancient Greek παλίμψηστος originally compounded from πάλιν and ψάω literally meaning “scraped...
remnants.
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 Planck.| Planck | Latitude | Longitude | Diameter |
|---|---|---|---|
| A | 54.7° S | 137.3° E | 19 km |
| B | 56.0° S | 137.4° E | 46 km |
| C | 53.4° S | 141.3° E | 43 km |
| J | 62.9° S | 145.3° E | 26 km |
| K | 65.0° S | 146.2° E | 23 km |
| L | 66.9° S | 141.8° E | 23 km |
| W | 56.0° S | 131.2° E | 17 km |
| X | 54.3° S | 129.5° E | 25 km |
| Y | 55.0° S | 132.0° E | 40 km |
| Z | 56.4° S | 135.2° E | 72 km |