Alter (crater)

Alter (crater)

Oblique Lunar Orbiter 5 image, facing west
Coordinates	18°42′N 107°30′W / 18.7°N 107.5°WCoordinates: 18°42′N 107°30′W / 18.7°N 107.5°W
Diameter	64 km
Depth	Unknown
Colongitude	108° at sunrise
Eponym	Dinsmore Alter

Alter is a lunar impact crater that is located in the northern hemisphere on the far side of the Moon. It lies to the southwest of the larger crater Robertson, and to the east of Ohm.

The outer rim of Alter has been degraded by subsequent erosion, most notably at the northern and southern extremes. There is a small crater lying across the south-southeast rim. A cleft runs across the floor from the southern rim toward the north-northeast. Ray material cross the crater floor from the east, forming a pair of faint bands.

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 Alter.

Alter	Latitude	Longitude	Diameter
K	16.3° N	106.0° W	22 km
W	20.4° N	109.2° W	52 km

References

• Andersson, L. E.; Whitaker, E. A. (1982). NASA Catalogue of Lunar Nomenclature. NASA RP-1097.
• Blue, Jennifer (July 25, 2007). "Gazetteer of Planetary Nomenclature". USGS. Retrieved 2007-08-05.
• Bussey, B.; Spudis, P. (2004). The Clementine Atlas of the Moon. New York: Cambridge University Press. ISBN 978-0-521-81528-4.
• Cocks, Elijah E.; Cocks, Josiah C. (1995). Who's Who on the Moon: A Biographical Dictionary of Lunar Nomenclature. Tudor Publishers. ISBN 978-0-936389-27-1.
• McDowell, Jonathan (July 15, 2007). "Lunar Nomenclature". Jonathan's Space Report. Retrieved 2007-10-24.
• Menzel, D. H.; Minnaert, M.; Levin, B.; Dollfus, A.; Bell, B. (1971). "Report on Lunar Nomenclature by the Working Group of Commission 17 of the IAU". Space Science Reviews 12 (2): 136–186. Bibcode:1971SSRv...12..136M. doi:10.1007/BF00171763.
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• Whitaker, Ewen A. (1999). Mapping and Naming the Moon. Cambridge University Press. ISBN 978-0-521-62248-6.
• Wlasuk, Peter T. (2000). Observing the Moon. Springer. ISBN 978-1-85233-193-1.