Kopff 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 An impact crater is a circular depression in the surface of a solid astronomical object formed by the hypervelocity impact of a smaller object. In contrast to volcanic craters, which result from explosion or internal collapse, impact craters ...

that lies along the eastern edge of the inner

Mare Orientale Mare Orientale (Latin ''orientāle'', the "eastern sea") is a lunar mare. It is located on the western border of the near side and far side of the Moon, and is difficult to see from an Earthbound perspective. Images from spacecraft have reveale ...

impact basin, on the western 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 position the crater is seen from on edge 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 ...

. This situation makes it difficult to discern much detail about the crater unless it is viewed from orbit. At one time this crater was considered to have formed due to volcanic activity,''The moon as viewed by lunar orbiter'', 1970, NASA SP-200 by L. J. Kosofsky, Farouk El-Baz in contrast to most lunar craters which are considered to have been created through impacts. However it is more likely that the crater was formed by an impact against a surface that was still partly molten. This has left the crater with a sharp-edged, circular rim and a flat, dark-hued interior floor. Indeed, the

albedo Albedo (; ) is the measure of the diffuse reflection of sunlight, solar radiation out of the total solar radiation and measured on a scale from 0, corresponding to a black body that absorbs all incident radiation, to 1, corresponding to a body ...

of the interior floor matches that of the

lunar mare The lunar maria (; singular: mare ) are large, dark, basaltic plains on Earth's Moon, formed by ancient asteroid impacts on the far side on the Moon that triggered volcanic activity on the opposite (near) side. They were dubbed , Latin for 'seas' ...

to the west. The southeast part of the floor is fractured with a series of narrow

rille Rille (German for 'groove') is typically used to describe any of the long, narrow depressions in the surface of the Moon that resemble channels. The Latin term is ''rima'', plural ''rimae''. Typically, a rille can be several kilometers wid ...

s. The floor along the northwest and northeast edges is more rugged, and these sections have escaped the lava that covered the remainder of the floor.

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 Kopff. The following craters have been renamed 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 ...

. * Kopff A — ''See''

Lallemand Lallemant is a French surname that may originate in the phrase "l’Allemand", meaning "the German." Variants of the name include: Laleman, Lalemand, Lalemant, Lalleman, L'allemand, and Lallemand. It may refer to: Persons *Charles Lallemant (1587� ...

References

* * * * * * * * * * * * {{cite book , first = Peter T. , last = Wlasuk , date = 2000 , title = Observing the Moon , publisher = Springer , isbn = 978-1-85233-193-1 Impact craters on the Moon