The geological features on Pluto are being identified by scientists working with data from the New Horizons spacecraft. The International Astronomical Union has determined that the names for these features will be chosen from the following themes:
The following is a list of unofficial names chosen by the New Horizons team but not yet approved by the IAU. Not all of the names correspond with the themes listed above.
A cavus is a hollow or steep-sided depression. One cavus has been identified on Pluto thus far; it is named after a mythological underworld.
A collis is a low hill. Plutonian colles are being named after spacecraft that operated in Earth orbit.
Plutonian craters are being named after scientists and other people associated with the study of Pluto.
A dorsum is a ridge. Plutonian dorsa are being named after underworlds in mythology.
A fossa is a ditch-like feature. Plutonian fossae are being named after figures associated with underworld myths.
A linea is an elongated marking. Plutonian lineae are being named after space probes.
A macula is a dark spot. Plutonian maculae are being named after underworld creatures from fiction and mythology.
A mons is a mountain. Plutonian montes (mountain ranges) are being named after explorers and adventurers.
A planum is a plateau or high plain. One (Sputnik Planum) was initially identified on Pluto; but it has since been recognized to be a planitia.
A planitia is a low plain, distinct from plana as they are located on lower terrain.
A regio is a region geographically distinct from its surroundings. Plutonian regiones are being named after underworld spirits in fiction and mythology, or after scientists associated with the study of Pluto.
A rupes in an escarpment. Plutonian rupēs are being named after explorers.