Challis (crater)

Challis

Location of the crater Challis.
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 midpoint 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. {{cite book}}: Invalid |ref=harv (help)
• Blue, Jennifer (July 25, 2007). "Gazetteer of Planetary Nomenclature". USGS. Retrieved 2007-08-05. {{cite web}}: Invalid |ref=harv (help)
• Bussey, B.; Spudis, P. (2004). The Clementine Atlas of the Moon. New York: Cambridge University Press. ISBN 978-0-521-81528-4. {{cite book}}: Invalid |ref=harv (help)
• 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. {{cite book}}: Invalid |ref=harv (help)
• McDowell, Jonathan (July 15, 2007). "Lunar Nomenclature". Jonathan's Space Report. Retrieved 2007-10-24. {{cite web}}: Invalid |ref=harv (help)
• Moore, Patrick (2001). On the Moon. Sterling Publishing Co. ISBN 978-0-304-35469-6. {{cite book}}: Invalid |ref=harv (help)
• Price, Fred W. (1988). The Moon Observer's Handbook. Cambridge University Press. ISBN 978-0-521-33500-3. {{cite book}}: Invalid |ref=harv (help)
• Rükl, Antonín (1990). Atlas of the Moon. Kalmbach Books. ISBN 978-0-913135-17-4. {{cite book}}: Invalid |ref=harv (help)
• Webb, Rev. T. W. (1962). Celestial Objects for Common Telescopes (6th revision ed.). Dover. ISBN 978-0-486-20917-3. {{cite book}}: Invalid |ref=harv (help)
• Whitaker, Ewen A. (1999). Mapping and Naming the Moon. Cambridge University Press. ISBN 978-0-521-62248-6. {{cite book}}: Invalid |ref=harv (help)
• Wlasuk, Peter T. (2000). Observing the Moon. Springer. ISBN 978-1-85233-193-1. {{cite book}}: Invalid |ref=harv (help)