Geissler is a small

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 on the northern floor of the much larger walled plain

Gilbert Gilbert may refer to: People and fictional characters * Gilbert (given name), including a list of people and fictional characters *Gilbert (surname), including a list of people Places Australia * Gilbert River (Queensland) * Gilbert River (South ...

, near the eastern 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 ...

. Just to the northeast of this crater, attached to the outer rim of Gilbert, is the crater pair of

Weierstrass Karl Theodor Wilhelm Weierstrass (german: link=no, Weierstraß ; 31 October 1815 – 19 February 1897) was a German mathematician often cited as the "father of modern mathematical analysis, analysis". Despite leaving university without a degree, ...

and Van Vleck. The rim of Geissler is nearly circular, with a slight outward bulge toward the northwest. The rim is sharp-edged and not notably worn. The inner walls are simple slopes that run down gradually to the small interior floor, which has a diameter about one third that of the crater. This formation is not significantly eroded, and is otherwise undistinguished. This crater was formerly designated Gilbert D before being assigned a unique name 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 1976.Geissler
Gazetteer of Planetary Nomenclature, International Astronomical Union (IAU) Working Group for Planetary System Nomenclature (WGPSN)

References

* * * * * * * * * * * * {{refend Impact craters on the Moon