Challis (crater)

Challis (crater)

Location of the crater Challis.
Coordinates	79°30′N 9°12′E / 79.5°N 9.2°E / 79.5; 9.2Coordinates: 79°30′N 9°12′E / 79.5°N 9.2°E / 79.5; 9.2
Diameter	56 km
Depth	Unknown
Colongitude	355° at sunrise
Eponym	James Challis

Challis is a lunar crater that is located in the northern regions of the Moon's near side, close enough to the limb to appear significantly foreshortened when viewed from the Earth. It is joined to the crater Main through a break in the northern rim, and is close to Scoresby along the southeast side.

The rim of this crater has been damaged and eroded by a history of impacts, with the most intact portion located along the southeastern half. A small crater lies across the southern rim, and the remaining rim is notched and irregular. The interior floor of both Challis and Main have been resurfaced forming a relatively level bottom common to both formations. This surface is marked only by multiple tiny craterlets.

Satellite craters

By convention these features are identified on lunar maps by placing the letter on the side of the crater mid-point that is closest to Challis.

Challis	Latitude	Longitude	Diameter
A	77.2° N	2.3° E	32 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. http://planetarynames.wr.usgs.gov/. Retrieved 2007-08-05. 
• Bussey, B.; Spudis, P. (2004). The Clementine Atlas of the Moon. New York: Cambridge University Press. ISBN 0-521-81528-2. 
• Cocks, Elijah E.; Cocks, Josiah C. (1995). Who's Who on the Moon: A Biographical Dictionary of Lunar Nomenclature. Tudor Publishers. ISBN 0-936389-27-3. 
• McDowell, Jonathan (July 15, 2007). "Lunar Nomenclature". Jonathan's Space Report. http://host.planet4589.org/astro/lunar/. 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.  edit
• Moore, Patrick (2001). On the Moon. Sterling Publishing Co. ISBN 0-304-35469-4. 
• Price, Fred W. (1988). The Moon Observer's Handbook. Cambridge University Press. ISBN 0-521-33500-0. 
• Rükl, Antonín (1990). Atlas of the Moon. Kalmbach Books. ISBN 0-913135-17-8. 
• Webb, Rev. T. W. (1962). Celestial Objects for Common Telescopes (6th revision ed.). Dover. ISBN 0-486-20917-2. 
• Whitaker, Ewen A. (1999). Mapping and Naming the Moon. Cambridge University Press. ISBN 0-521-62248-4. 
• Wlasuk, Peter T. (2000). Observing the Moon. Springer. ISBN 1-85233-193-3.