| Feature |
Description |
Designation |
| Albedo Feature |
Geographic area distinguished by amount of reflected light |
AL |
| Arcus, arcūs |
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, flexūs |
A very low curvilinear ridge with a scalloped pattern |
FE |
| Fluctus, fluctūs |
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, labēs |
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, rupēs |
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, sinūs |
"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 |