Astrogeology Research Program

Gazetteer of Planetary Nomenclature

Descriptor Terms (Feature Types)

Feature	Description	Designation
Albedo Feature	Geographic area distinguished by amount of reflected light	AL
Arcus, arcÅ«s	Arc-shaped feature	AR
Astrum, astra	Radial-patterned features on Venus	AS
Catena, catenae	Chain of craters	CA
Cavus, cavi	Hollows, irregular steep-sided depressions usually in arrays or clusters	CB
Chaos	Distinctive area of broken terrain	CH
Chasma, chasmata	A deep, elongated, steep-sided depression	CM
Colles	Small hills or knobs	CO
Corona, coronae	Ovoid-shaped feature	CR
Crater, craters	A circular depression	AA
Dorsum, dorsa	Ridge	DO
Eruptive center	Active volcanic centers on Io	ER
Facula, faculae	Bright spot	FA
Farrum, farra	Pancake-like structure, or a row of such structures	FR
Flexus, flexÅ«s	A very low curvilinear ridge with a scalloped pattern	FE
Fluctus, fluctÅ«s	Flow terrain	FL
Flumen, flumina	Channel on Titan that might carry liquid	FM
Fossa, fossae	Long, narrow depression	FO
Insula, insulae	Island (islands), an isolated land area (or group of such areas) surrounded by, or nearly surrounded by, a liquid area (sea or lake).	IN
Labes, labÄs	Landslide	LA
Labyrinthus, labyrinthi	Complex of intersecting valleys or ridges.	LB
Lacus	"Lake" or small plain; on Titan, a "lake" or small, dark plain with discrete, sharp boundaries	LC
Landing site name	Lunar features at or near Apollo landing sites	LF
Large ringed feature	Cryptic ringed features	LG
Lenticula, lenticulae	Small dark spots on Europa	LE
Linea, lineae	A dark or bright elongate marking, may be curved or straight	LI
Lingula, lingulae	Extension of plateau having rounded lobate or tongue-like boundaries	LN
Macula, maculae	Dark spot, may be irregular	MA
Mare, maria	"Sea"; large circular plain; on Titan, large expanses of dark materials thought to be liquid hydrocarbons	ME
Mensa, mensae	A flat-topped prominence with cliff-like edges	MN
Mons, montes	Mountain	MO
Oceanus	A very large dark area on the moon	OC
Palus, paludes	"Swamp"; small plain	PA
Patera, paterae	An irregular crater, or a complex one with scalloped edges	PE
Planitia, planitiae	Low plain	PL
Planum, plana	Plateau or high plain	PM
Plume	Cryo-volcanic features on Triton	PU
Promontorium, promontoria	"Cape"; headland promontoria	PR
Regio, regiones	A large area marked by reflectivity or color distinctions from adjacent areas, or a broad geographic region	RE
Reticulum, reticula	reticular (netlike) pattern on Venus	RT
Rima, rimae	Fissure	RI
Rupes, rupÄs	Scarp	RU
Satellite Feature	A feature that shares the name of an associated feature. For example, on the Moon the craters referred to as "Lettered Craters" are classified in the gazetteer as "Satellite Features."	SF
Scopulus, scopuli	Lobate or irregular scarp	SC
Sinus, sinÅ«s	"Bay"; small plain	SI
Sulcus, sulci	Subparallel furrows and ridges	SU
Terra, terrae	Extensive land mass	TA
Tessera, tesserae	Tile-like, polygonal terrain	TE
Tholus, tholi	Small domical mountain or hill	TH
Undae	Dunes	UN
Vallis, valles	Valley	VA
Vastitas, vastitates	Extensive plain	VS
Virga, virgae	A streak or stripe of color	VI

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