Planetary Cartography

Craters and Projections

6609.1 - Conventions of designating unnamed planetary surface features

Thursday, July 6
2:50 PM - 3:10 PM
Location: Harding

Unnamed small and larger features in planetary surface feature databases and research papers need some kind of designation. We have reviewed the literature and existing databases and compared the conventions of designating features that are not named by IAU. We have identified four separate decisions that may be made in order to produce a coherent ID system during the naming process, : the designations’ connections to existing names, the spatial range of existing names that may affect the designations, the designation itself, and the rules of their succession.
An example is Mars, were small features were initially proposed to be designated by their coordinates and not names (Sadler 1960:260). “Very small features requiring identification” were approved as a separate category on the Moon but their names cannot have more than three syllables (Contopoulos, A. Jappel 1973:112).
Today smaller feature types remain completely unnamed. According to the IAU WGPSN rules, “official names will not be given to features whose longest dimensions are less than 100 meters” (IAU 2016). On Mars, a total of six features less than 1 km in diameter are named (all craters). On the Moon, most of these small named features are around landing sites. Features of this order of magnitude on Mars include gullies, RSLs, dunes, cratered or noncratered positive relief cones, mounds and knobs, skylights (some named informally), landslides, yardangs, smaller channels (fresh shallow valleys) and tributaries, deltas (of unnamed canyons and valleys), glacier-like forms, spiders, patterned ground and groups or fields of the above mentioned forms.
These are now not only seen and studied around landing sites, but also from orbital images (the HiRISE camera has a resolution of 25 cm/pixel). One exception may be some of the sinuous ridges which are named using the term dorsa or serpens. All these unnamed features remain nonexistent in the toponymic layers of maps.
Informal names and designations include IDs in feature catalogs which are ad hoc systems using coordinates, letters, map quad names, numbers or a combination of these. Some features already have different designations in different catalogs. For example, a small fissure shield volcano at 4.71°N 158.96°E on Mars is designated B, CepB, and EQ2 in three different catalogs published around the same time (see Hargitai 2016).
Another class of Informal names are those of surface features identified from orbital imagery. On the Martian polar cap include for example Inca City, Starfish, Ithaca, Finger Lake, Caterpillar, Oswego and Giza (Hansen et al. 2007) and are used commonly for almost 10 years now, functioning as regular names: to designate regularly studied areas on the surface.
The most abundant source of informal names are those at landing sites of automated landers and along the traverses of rovers. These include names of rocks (Big Joe, Viking 1 Landing site, PIA00572; Yogi, Mars Pathfinder image 81696), and a wide variety of features, for example, in one site, the Yellowknife Bay formation visited by Curiosity, local names include Gillespie Lake, Sheepbed, Point Lake, John Klein drill site, Cumberland drill site (Image PIA17595).
Using coordinates for identification has limitations as the smaller the feature the more decimals should be used and these cannot be used beyond a certain precision depending on the planetary body.

Henrik I. Hargitai

Postdoctoral Researcher
NASA Ames Research Center

Henrik I. Hargitai (Ph.D., 2007) is a planetary geomorphologist and media historian. He is a postdoctoral fellow at the NASA Ames Research Center. He taught planetary geomorphology, planetary cartography, typography, and media history as a senior lecturer at Eötvös Loránd University, Budapest, Hungary since 2002. He has a Ph.D. in Earth Sciences and Philosophy (Aesthetics). His study fields include planetary cartography, fluvial geomorphology, and the history and localization of planetary nomenclature. He participated in two Mars Desert Research Station simulations. He is the chair of the ICA Commission on Planetary Cartography.


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Mátyás Gede

Senior lecturer
Eötvös Loránd University

Mátyás Gede is a senior lecturer at the Department of Cartography and Geoinformatics, Eötvös Loránd University, Budapest. His main fields of interest are globe digitising, virtual globes, webcartography and map projections. He is the vice chair of the ICA Commission on Cartographic Heritage into the Digital.


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6609.1 - Conventions of designating unnamed planetary surface features


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