Alter (crater)

Alter

Oblique Lunar Orbiter 5 image, facing west
Coordinates	18°44′N107°48′W / 18.74°N 107.80°W / 18.74; -107.80
Diameter	64.73 km (40.22 mi)
Depth	Unknown
Colongitude	108° at sunrise
Eponym	Dinsmore Alter

Satellite craters of 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.

Prior to formal naming by the IAU in 1970, ^[1] Alter was called Crater 257. ^[2] The crater Alter W, to the northwest of Alter, was called Crater 255. A crater that is currently unnamed, between Alter W and Comrie K, was called Crater 254.

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

1. Alter, Gazetteer of Planetary Nomenclature, International Astronomical Union (IAU) Working Group for Planetary System Nomenclature (WGPSN)
2. Lunar Farside Chart (LFC-1A), 2nd Edition October 1967

• 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. S2CID   122125855.
• Moore, Patrick (2001). On the Moon. Sterling Publishing Co. ISBN   978-0-304-35469-6.
• Price, Fred W. (1988). The Moon Observer's Handbook. Cambridge University Press. ISBN   978-0-521-33500-3.
• Rükl, Antonín (1990). Atlas of the Moon. Kalmbach Books. ISBN   978-0-913135-17-4.
• Webb, Rev. T. W. (1962). Celestial Objects for Common Telescopes (6th revised ed.). Dover. ISBN   978-0-486-20917-3.
• 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.

External links

• Media related to Alter (lunar crater) at Wikimedia Commons