The Mendel-Ryberg Basin is a

Nectarian The Nectarian Period of the lunar geologic timescale was from 3.920 billion years ago to 3.850 billion years ago. It is the period during which the Nectaris Basin and other major basins were formed by large impact events. Ejecta from Nectaris for ...

USGS The United States Geological Survey (USGS), founded as the Geological Survey, is an government agency, agency of the United States Department of the Interior, U.S. Department of the Interior whose work spans the disciplines of biology, geograp ...

Professional Paper 1348. By Don E. Wilhelms, John F. McCauley, and Newell J. Trask. U.S. Government Printing Office, Washington: 1987. Table 9-3. impact basin on the southwestern limb of the

moon The Moon is Earth's only natural satellite. It Orbit of the Moon, orbits around Earth at Lunar distance, an average distance of (; about 30 times Earth diameter, Earth's diameter). The Moon rotation, rotates, with a rotation period (lunar ...

. It is named after the crater Mendel on the west margin and the smaller crater Rydberg north of the center of the basin. The basin is due south of the larger, younger Orientale basin.

Ejecta Ejecta (; ) are particles ejected from an area. In volcanology, in particular, the term refers to particles including pyroclastic rock, pyroclastic materials (tephra) that came out of a explosive eruption, volcanic explosion and magma eruption v ...

and other geomorphological effects from the younger basin have overprinted the older one. At the center is a mass concentration (mascon), or gravitational high. The mascon was first identified by Doppler tracking of the Lunar Prospector spacecraft. The existence of the basin was confirmed by the GRAIL spacecraft. Other craters within the basin include Guthnick, De Roy, Arrhenius, Yakovkin, Graff, Andersson, Chadwick, Fényi, Blanchard, and Baade. Vallis Baade cuts tangentially across the northeast rim of the basin. Nearby craters just outside the outer rim include

Drude In German folklore, a drude (, , pl. ''Druden'') is a kind of malevolent nocturnal spirit (an alp, kobold or hag) associated with nightmares, prevalent especially in Southern Germany. Druden were said to participate in the Wild Hunt and we ...

, Chant, Steklov, Lippmann, Petzval, Chappe, Pilâtre, Hausen, Pingré, and Inghirami. The large crater Bailly is to the southeast, and to the west beyond Lippmann is the

South Pole-Aitken Basin South is one of the cardinal directions or compass points. The direction is the opposite of north and is perpendicular to both west and east. Etymology The word ''south'' comes from Old English ''sūþ'', from earlier Proto-Germanic ''*sunþaz ...

. File:Mendel-Rydberg basin topo.jpg, Topographic map File:Mendel-Rydberg basin GRAIL gravity.jpg, Gravity map based on GRAIL

References

{{reflist Impact craters on the Moon LQ28 quadrangle