Cusanus is a

lunar Lunar most commonly means "of or relating to the Moon". Lunar may also refer to: Arts and entertainment * ''Lunar'' (series), a series of video games * "Lunar" (song), by David Guetta * "Lunar", a song by Priestess from the 2009 album ''Prior t ...

impact crater that is located near the northeastern limb of the

Moon The Moon is Earth's only natural satellite. It is the fifth largest satellite in the Solar System and the largest and most massive relative to its parent planet, with a diameter about one-quarter that of Earth (comparable to the width of ...

. In this location the crater appears very foreshortened when observed from the

Earth Earth is the third planet from the Sun and the only astronomical object known to harbor life. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. About 71% of Earth's surfa ...

, and its visibility is affected by

libration In lunar astronomy, libration is the wagging or wavering of the Moon perceived by Earth-bound observers and caused by changes in their perspective. It permits an observer to see slightly different hemispheres of the surface at different tim ...

. The northern rim of Cusanus is nearly joined to the south-southeastern rim of the larger crater Petermann. To the west is Baillaud and to the southeast is Hayn. The rim of this crater has been eroded and rounded due to a history of minor impacts. The

terrace Terrace may refer to: Landforms and construction * Fluvial terrace, a natural, flat surface that borders and lies above the floodplain of a stream or river * Terrace, a street suffix * Terrace, the portion of a lot between the public sidewalk a ...

s are still visible along the inner walls, although they are less sharply defined compared to younger crater formations. A pair of tiny craters form a notch along the eastern rim, and there is a slight inward bulge along the western inner wall. The interior has been resurfaced with

lava Lava is molten or partially molten rock (magma) that has been expelled from the interior of a terrestrial planet (such as Earth) or a moon onto its surface. Lava may be erupted at a volcano or through a fracture in the crust, on land or un ...

, leaving a flat and relatively featureless floor. But the lava was not of sufficient depth to significantly reduce the width of the inner walls. The name of the crater was approved by the

IAU The International Astronomical Union (IAU; french: link=yes, Union astronomique internationale, UAI) is a nongovernmental organisation with the objective of advancing astronomy in all aspects, including promoting astronomical research, outreach ...

in 1935.Cusanus
Gazetteer of Planetary Nomenclature, International Astronomical Union (IAU) Working Group for Planetary System Nomenclature (WGPSN)

Satellite craters

By convention these features are identified on lunar maps by placing the letter on the side of the crater midpoint that is closest to Cusanus.

References

* * * * * * * * * * * * Impact craters on the Moon {{Craters on the Moon: C-F