PLANETARY MAPS: VISUALIZATION AND NOMENCLATURE

Henrik I. Hargitai Eötvös Loránd University, Cosmic Materials Space Research Group, 1117 Budapest, Pázmány P. st. 1/A Hungary, hargitaihenrik@emc.elte.hu

Planetary maps serve several purposes: they are documentation of our discoveries and current knowledge, an everyday tool for the scientific community, and for the non experts - the public, interested students, children - they are attractive representations of strange new worlds. Maps of other planetary bodies - especially with landing sites marked - show that human kind has acquired a new territory in its - our - oikumene. Every new detail in planetary maps adds a new place to this known world. They do not exist until they are displayed on the map even if scientific papers discuss them. Maps are the visual catalogue of the Places Occupied - by our scientific knowledge. They show planets as places instead of dots in the sky. They also show visually and globally how little and how much the other planets are different from the Earth, this way demystifying them and at the same time highlighting Earth’s uniqueness in the known Universe. Planetary maps constitute of at least three thematic layers: base image (either photomosaic, shaded relief, color-coded topography, geology etc.), grid and nomenclature. Our current state of knowledge of c. ten large and numerous smaller planetary surfaces makes it possible to produce more complex, multi-thematic maps that “compress” our knowledge into one single map sheet. For the scientific community, for a specific use, the best maps are large scale thematic (geologic and computer generated topographic) maps; however, for the general public, small scale global maps are adequate. These should contain several thematic layers, the same way as geographic maps do. On the initiation of Moscow State University for Geodesy and Cartography (MIIGAiK) several groups in Europe are working on a Multilingual Planetary Map Series, and, as a next phase of this project, the Cosmic Materials Space Research Group of Eötvös Loránd University, Hungary, is working on a new multilayered map series. At this group we have conducted a survey amongst students and amateur astronomers asking them about our series. We have modified our maps according to the results of the survey. We also gave special mapping tasks to students during regular classes. Most students look for symbols and patterns that are already familiar for them from terrestrial physical geographic maps and school atlases. In this paper we summarize how we produce our series, which thematic layers we use, and what kind of problems we face in producing our printed maps. Our goal is to produce maps that not only are attractive ones, and contain the required scientific contents, but maps on which both visual and textual elements are easy-to-understand by the everyday people.

Responsibility of the cartographerPlanetary map is a powerful tool which can manipulate the view of the map reader on the mapped planet. This manipulation capacity of the map is well known from terrestrial maps that were used for some political purpose. If the planetary cartographer whose task is to make a map for the general public uses these tools one way - for example Latin names, special color coding, geologic symbols etc - it can suggest that the studying of the planet can only be made by scientist - those who are not experts have no chance to understand the nature of processes and features on that surface. While using them another way - translated nomenclature, rich textual (interpreting) information, familiar symbols and colors -, the maps contents communicate that the processes and features are not (so) special and can be understood. It also suggest that the same basic processes operate on all planets. This way it can even have an effect on the public (or the map users’ individual) support of space missions: it can bring a planet closer to our everyday geographic experience. This suggest that the planet should be or worth

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visiting. Other maps can communicate the opposite view creating the mental image of an alien world we should never (worth) visiting. It is therefore important that the cartographer be aware of the ways an other planetary body can be visualized using the tools of cartography. The basic problem in this case is that most planetary maps made for the general public are not made by cartographers but usually by planetary scientists or designers or by computer software engeneers (the same is true for maps made for media use [weather forcast maps, newscast maps etc.]), or a combination of them, but in most cases without a professional cartographer (of course, USGS maps are exceptions, but these are scientific maps which are not the subject of this paper). Thus, they have to learn the basic rules of cartography if they want to produce good maps - or cartographers have to start woking on this field. An other problem is that maps of several planetary bodies are not available in most languages. Even maps of terrestrial planets and the Moon are absent in many languages or only outdated ones can be obtained - from libraries. Bookshops usually sell only English/German language maps.

The world atlas maps: small-scale Mercator series If World Atlases have a section for other planets, they usually include photos of the planet, diagrams of their orbits and their interior structure together with short descriptions and a data. Interestingly, the planetary section usually has no - maps. Since these Atlases are made for the public, they are not made for use as tourist or city maps: the map sheets of Antarctica or of the sea floors can serve the same purpose as planetary maps would. A Hungarian publishing company Topográf has agreed to include a section for small scale planetary maps in the new editions of its World Atlas (Hargitai et al, 2003-2004). For this work the group in Budapest has started a new series, using topographic color coded Mercator maps instead of the two-hemisphere hand-drawings which were used in the MIIGAiK-made series. The only exception was the Moon, which is the only planetary body we actually can observe: we used the two-hemisphere hand drawn map here because it better visualizes the visible surface of the Moon. In all these maps we use Hungarian nomenclature. (Fig.1) Our goal is to depict other planets the same way as we do it in terrestrial maps: as Places.

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Fig. 1. Pages from the World Atlas of Topográf Publishing Co, Hungary: as a result of a compromise, the Atlas includes both images and planetary maps.

Survey, test mapsWe have shown our maps together with other test maps to university and middle school students and amateur astronomers and asked questions about them. We wanted to know what they understand well and what they could not understand (or not even percept) (terms, colors, data, nomenclature etc); what they cannot find (or miss), what new (or surprising) information they learned from the map - and what they generally expect from a planetary map. We wanted to know whether our Hungarian nomenclature - in which the generic parts of the geographic names were translated, while the specifics were left in their original forms - is better or not for understanding the alien landscape. We have made a map of Mars (from the Mercator series) and the Moon (from the 2-hemisphere wall map series, Fig. 2-3.), one in Hungarian, and one in the official Latin IAU nomenclature in both cases. To have information about how they could decode the map content, we asked them to describe the geography of Mars/Moon, using the map only (they had no or very limited prior knowledge) and we asked them where would they land on Mars/Moon. We also asked directly what elements of the map they did not understand and what more they would want to know about Mars/Moon. The maps were distributed randomly to 100 middle school students, 100 university student, studying communication and media studies, and c. 20 amateur astronomers, all in Budapest.

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Fig. 2. Multilingual map of the Moon supported by ICA Commission on Planetary Cartography. (Hargitai et al. 2003) The large features are written in large letters in its IAU (Latin) form, and are translated to six other languages (traditional use) in smaller letters. The map is also multiscriptual, since Russian spacecraft and crater names are written in Cyrillic letters (most readers in the target audience can read them). Smaller features have not been translated. The map is intended to be used in Central European countries.

Fig. 3. The test map of the Moon (Hargitai et al 2003-2004) based on the map shown above. Here the local exonym is shown in large letters, while the IAU Latin form is in smaller ones. The names of features other then Mare or Palus are only shown in an experimental standardized way, e.g. the specific part always the same as in the IAU form, but the generic part is always translated. This method appeared to be unsatisfactory for astronomers in the case of those features that already has traditionally used exonyms (Carpatus Montes: Kárpátok), but works with other features. All originally Cyrillic written names are transcribed to Hungarian according to the rules of the Hungarian Academy of Sciences (which differs from the English/IAU rules). The widely used Greek person’s names are also transcribed according to these rules – the less known names are kept in their Latinized IAU form.

Results of the survey: the problems

Nomenclature, terminology

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On the translated test map the specifics were all kept unchanged while the generics were all translated. This way we have used transformation rules that had no exceptions, in order to produce a nomenclature from which the original form can be easily re-established. The results were different in our two focus groups (students and amateur astronomers). The students haven’t noticed (consciously) the difference of the two versions, but it was clear from the responses to the task “describe the geography of Mars/Moon” that they could “visualize” the landforms using the map with translated nomenclature, while using the IAU nomenclature they just copied the Latin terms without understanding the nature of features they were referring to. In the amateur astronomer group - who use IAU names on a daily basis in their observation work - one part of the group disliked our way of translation, saying that we should have used the traditional (exonym) forms (Kárpátok instead of Carpatus-hegység for Carpatus Montes). They argued that the forms that have no tradition (even if it makes it easier to find the original form), should be avoided. The other part of the group argued that both Latin and Hungarian (endo/exo/nym) should be used, especially in the case of lunar maria. In the case of Mars, many of them use some of the albedo nomenclature, and only a few features are in common use from the “new” nomenclature. While they easily accepted the translated names for the less known features (Isidis-medence), they kept on using the Latin names for the best known features (Olympus Mons). This resulted in a mixed nomenclature which definitely should be avoided.

The other focus group - university and middle school students - had the following problems. — It was unclear for the map readers what the crater names were referring to. Since they have no descriptive element included in their names (the word crater is not part of the name), it must be made clear that they are the names of craters (by its positioning, or small dot signs in the center of craters, or in the explanations section).— Why are the lunar basins called seas/maria once they did not contain water - they asked the “traditional” question. Of course they are not seas of water but can be explained as seas of basaltic rocks (it will be interesting to follow the naming process of Titan, which do have seas of fluid material). — The rays around lunar young craters remained an enigma for the readers, since nothing explained their nature while they were clearly visible even in small scale (they have no names). — Many missed mountain peak names and peak height data for both Mars and the Moon. This was probably the most interesting and useful result of the survey. Mountain peaks - if they are defined at all - has traditionally no names and (therefore?) are not included in planetary maps. Since such data can be extracted from the newly acquired MOLA data or Clementine Lunar Laser Altimeter measurement, this can be changed in the future. Such height data is usually not included in planetary maps or even scientific maps and publications - while, as the survey showed clearly, most map readers “need” it. They also asked for the depth data of some deep basins or maria. — “Where is the Face on Mars”, some asked. It shows that they do want to know the positions of the features whose informal names appear in popular press or are used informally by scientists as well (Inca City, Cobra Head or recently Frozen Ocean, Sissy the Cat etc). — They wanted to know the naming process; — “What is the 0 m level in the absence of a sea” - the datum of both elevation and 0 longitude needs explanation

Other problems with map reading— Lunar/Venusian lava channels and Martian valleys of various types, along with other linear features are usually not appearing on planetary maps, only if their topography is deep enough to show up in

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topographic maps. (In one case (Hartmann 2003) the position of Marte Vallis is explained in detail in the caption of a map, saying that unfortunately it can not appear in the topographic map - this is one example when more creative mapping would be needed).— Many answered that the bluish color (for low topography) is misleading, since it is the color of water. They suggested to use a brownish hue instead.— Many missed the location of ice (caps) on Mars (and Moon). The polar caps, as in other topographic maps, were first depicted using the colors corresponding to their topographic level. They asked for using bluish white instead.

Novelties and questions without answers The followings were mentioned as new information they learned from the maps: — Many told that they were surprised by the large number of named features and also the many landing sites.— Many told that they previously thought that only small height differences exist on Mars: the high volcanoes and deep chasms showed them a new landscape. The maps did not answer the following questions: “Where is life on Mars?”, “What materials are the features composed of”, “How the features were formed”.

The final mapsAfter evaluation, we have changed the maps and these new maps (Fig. 4-5.) were shown to 50 university students studying geography to see if our changes made them better or not. The results were positive: none of the earlier problems arose, and the new problems were individual, i.e. not repeated by more than one student. In the followings, we describe why, what and how we modified the maps.

Fig. 4. The test map of Mars (detail) with Latin nomenclature.

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Fig. 5 Map of Mars (the same detail as above): first preliminary version after correction with Hungarian nomenclature. This map is not considered as final product, since new symbols, details, comments are inserted continuously.

Research for map producing Several feature types has been recognized only in recent years and the extent of some features are not yet mapped globally or not mapped at all, or mapped and classified differently by different authors. In these cases the mapmaker has to use primary resources (scientific articles or images) to find the necessary data for the map. There is a need for a clear guide or database of the landform types of the Solar System. This is a prerequisite for all maps, since for the generalization and symbols used in the map, we must previously know what groups and types of features will or can appear on the map. Such database should contain landforms listed by their geology, morphology, coordinate, IAU and other informal names. There is also need for a catalogue of the historic (or diachronic) terminology in planetary science: during the decades the terms applied for certain features changed, or the same name is used differently (Almár 2005).

Maps are to read, not only to seeThe readers find an alien world on the map. Many of the surface forms has no terrestrial parallels, thus we can't have experience to imagine them. Without an existing mental representation, the used symbols and the generalization should help readers properly identify the features. Since many of the landforms don't appear on maps of the Earth, the cartographer has to find a new (system of) symbols for them. A map readable for the „general user” should contain geologic, stratigraphic, albedo, morphologic, topographic and historic (landings) information to make the map better interpretable and understandable. Most planetary maps are very small scale maps. Thus they can only show a limited variety of features, however, most of the interesting features are of relatively small size. Carefully selected cutouts and/or generalization can help to highlight the location of these landforms (in the case of Mars: landslides, layered crater deposits, DDS’s, small valleys, calderas etc). Easy interpretation of our symbols is important: the existing geologic symbols can only be used to a limited extent in such a map. A parallel may be the scientific maps of meteorologists versus the weather maps appearing on TV screens or newspapers. The latter contains the same information but with more stress on design elements. Usually when speaking about a geographic / geologic / climatic etc. phenomena, everyone can visualize its typical area where it can be found on Earth: we all have a cognitive map of landscape types and

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features, as well as for some place names. This is, however, not true for other planets. We now enter the age, when detailed investigation begin and (photo-) maps of other planetary bodies are available via the internet. News about features and research results appear on a regular basis in newscast and newspapers. We believe that to form a true cognitive image of other planets and better understand their geologic/climatic systems, people should connect the known data (textual information, which sometimes includes place names) with visual spatial information: locations on a map. For this, the visual appearance and the accompanying textual contents of maps (colors, nomenclature, symbols etc.), and also the environments where these maps are available (school walls, World Atlases, textbooks - or in electronic form) are crucial factors – the same way as maps of the Earth have formed the mental picture of our home planet for many centuries since the world map of Agrippa in the 1st century B.C. For the cognitive map, the reader needs “hooks”, well recognizable patterns on the map. On the Earth, this is the contour line of sea level (i.e. outlines of continents and islands) and the blue lines of rivers: both related to hydrology. On other planets (except may be from Titan) this system is absent: the cartographer has to find the best basic pattern from which a planet or a part of it can be readily recognized - as a System of Places. This is essential if we want to avoid the general belief of “one planet - one landscape” (Mars=desert without topography), or, worst, “one planet - one astrological sign”.

Multilayered map We try to look at planetary maps in a new way: as if they were maps of an area on Earth. Terrestrial maps have a tradition of hundreds of years, while planetary maps have only half a century (except for the Moon). The surface of the Earth is a complex system of artificial and natural features. Even the simplest maps showing the Earth have several layers of different content (grid, country boundaries, still water bodies, rivers, topography, coloring based on height and vegetation, cities etc.), nomenclature of artificial and natural features (sometimes undersea features), index, explanations, scale bars etc. while most planetary maps has only one such layer (only topography or only photomap or only geology) usually without a detailed nomenclature and index and very limited explanations (usually only the color coding of heights). Scale bars, on the other hand, regularly appear even on photos because it is hard to estimate the order of magnitude of the depicted area. Using the traditional complex system of terrestrial maps, planetary maps can be easier to read. Such map would be a composite map of several thematic layers. The important but too small landscape features would be indicated only by generalized symbols, while others would look realistic. It would show selected “hot spots” or “candidate scientific tourist attractions”.

The features of the mapsColor coded topography —We have changed the colors of the deep basins and plains into lighter yellowish instead of darker blue. The use of greenish and bluish hue on terrestrial maps refer not only to height, but also to surface cover: water and grass vegetation, respectively. On other planets, because of this second reference, these colors should be avoided. We used yellowish-brown hue throughout the map of Mars (altering it according to the topography) that indicates its dry, desert-like characteristic. The light yellowish color of depths on Mars are also associated to light colors of frost as seen by terrestrial observations. We have tried a common color coding system using the same height = same color system for all planetary bodies, but it failed to work, since characteristic features of different planets show up in very different scales (Lunar maria vs. Venusian continents vs. Martian north-south difference). Color

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differences should highlight in some cases extreme, in other cases minimal height differences, in various parts of the same planet (Lunar mountains vs. maria vs. SPA Basin) or in different planets (Lunar vs. Martian volcanoes).Currently we have global topographic maps for Mars (MOLA), the Moon (Clementine), Venus (Magellan) and the Earth (Shuttle Radar), and regional, relative topographic maps from stereo measurements for several other planetary bodies (Mercury, Io etc). Color coded topographic data was mixed with actual images of some features (optical, false color or radar), or even ephemeral compositional data (polar ice, sand dune fields). Shaded relief In the case of shaded relief maps the base color of the shaded relief background gives a characteristic color to the particular map, which is not necessarily the same hue as the planet’s real color. It is always a debated question which exact color to choose. In shaded relief maps the base color can be changed according to geologic data, for example to highlight compositional, stratigraphic differences (mare/terra or andesite/basalt/anorthosite or hematite rich areas etc) Using different but harmonic color variants can indicate various geomorphic landscape types. Shading If the planet is shown as two hemispheres, the planet can be displayed with limb darkening or other shadowing, thus making the map look 3-D “realistic”.Albedo Several kinds of visible albedo features highlight ephemeral phenomena: wind streaks (wind direction), dark sand covered areas, latest lava flows, crater rays, dust devil tracks, DDS’s etc. These wide variety of features usually tell us about the ever changing processes that are actually shaping the planet’s surface. There are photographs from over 60 years which show the changing area of dark sand covered areas in Syrtis Major. It is a question, whether a map should show these features or not. If we decide to show them, it can be done using vectoral areal pattern symbols (as for deserts) or individual symbols. For those features that are only seen in radar wavelengths (showing rough surface in light, smooth in dark colors), radar reflectance images can be used as raw materials. Ice, frost Another ephemeral feature is related to temperature change. They can have an extra color which does not refer to its height: polar caps, seasonal extents of polar caps (ephemeral / climatic phenomena) or frost covered craters. It is good to bear in mind that in most terrestrial maps, Antarctica and Greenland is always shown in with its ice cover (instead of the base “silicate continental” topography), which is in fact an „ephemeral/volatile” phenomena, while for the northern ice cap, it is usually not shown (its extent changes considerably during the year). We decided to show the ice caps as white areas, and not according to its topographic height. Since the extension of Martian ice/frost caps vary, it is advisable to show its seasonal borders. We have shown the maximum extent as dotted white line and the minimum extent as white area. Other borderline features can also be shown on the maps: (estimated) boundary of permafrost, possible ocean shorelines on Mars etc. Fluvial features We have shown the linear valley features with lines similar to terrestrial rivers; but with dotted/dashed lines (differentiating the various [outflow/network] valley types) and magenta/orange-brown colors (Fig 6). Places of possible paleolakes (or lacustrine sediment) can be shown by symbols. These data should be extracted from other publications or photomosaics.

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Fig 6. Black and white, small scale, small size (12 cm) map showing Mars (with a nomenclature in Hungarian language). This map is an illustration for an article about water and ice on Mars.

Small scale features and patterns For a global map it can be useful if it could show features that are too small to depict to scale on the map. Such are craters on Venus; polygonal patterned ground, table mountains, cone/dome fields, dunes (in valley, in crater etc), pancake volcanoes, rampart craters, gullies etc.). These can have its own symbols, or - as we did - can be indicated using short comments placed at the proper place. — On Venus, we have used a radar-image based crater symbol for each larger crater. This way the apparent size of these crater images are larger than the features they refer to, but they are used as symbols for craters – making them clearly visible and characteristic. We also used radar based details for some crater flows, in their true size.

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Patterns Instead of showing each small crater in its place, a “cratered terrain pattern” can be used to show this landscape type, like as some new terrestrial Atlas pages show various agricultural and vegetation areas. This technique can also show patterned ground, mare terrains etc.: landscapes that has a small but repetitive feature. Artificial features Landing sites: names of landing / crashing sites of spacecrafts together with the date of landing, name of rovers, or quantitative data about them were shown using a color that differs considerably from the general hue of the map.Extra Symbols We are working on creating new symbols and textures for planetary features. For this work first we have catalogued the volcanic, aeolian, fluvial, karst, biogenic, large scale crustal, tectonic, mass movement and impact feature types (landforms) of all known planetary bodies. Symbols can be based on the Planetary Geology Feature symbols used by USGS (USGS 2004) but they have to be modified to fit the needs of the general public. — On the Venus map we have made a vectoral circle symbol to show coronae, which are not very well visible in the topographic map. We also used vectoral parallel lines (as symbols) to show fossae systems.Comments We have put short explanatory texts to the appropriate locations, for special phenomena and feature types. This works better than creating too many new symbols. Some of the comments include information related to the climate, geologic history, man-made objects, reflectance, morphology and age of landforms etc.Geographic data— We have shown exact (or: up to date) height data for the highest peaks and deepest basins. — Valley length /depth data, caldera depth data can also be included as crater rim height data (from shadow measurements) are included in several Lunar maps— We put more emphasis on the data of surface area instead of body diameter since it makes the planet better comparatible with our terrestrial experienceLanguages Languages used on the multilingual maps (five languages) were proved to be too much (requiring too much space). We decided to use only one local and the English language in one printed sheet and decided to make separate printings for each languages. Grid and datum— we have showed both old and new longitude system for Mars, explaining separately why we did it so— for each planetary body, the special latitude lines can be shown (tropics, arctic circles) according to its axis tilt. It can be related to the position of the local polar star. — We have included remarks about the current zero height levels.— It is possible to give a remark about the definition of the 0 longitudeExplanation, index — we have included a detailed explanation of symbols, where all landform symbols - areal, vectoral, - height levels, and nomenclature terms are explained, including the “termless” crater names and other features without names. In the explanatory part, we used geologic/geographic terms instead of or in addition to the IAU Latin descriptive terminology. Where space permitted, we included photos for explanation. — we have included a scale bar, together with textual explanation of how many cms correspond to how many kms. It is also a good method to draw the outline of the target audiences home country to the scale of the map. — we have included an index of names with coordinate and size (as in IAU Gazetteer).

Nomenclature, Fonts

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— We have shown informally named features (Face on Mars, Happy Face crater, Inca City, Cobra Head) with short explanations on the map. The function of using different fonts consistently is important: carefully selected font faces provoide another aid for the correct interpretation of a particular feature. Its nature thus is told by its 1) visual representation (shape, color), 2) name (generic element) and 3) the font face, style and size of its name. The terrestrial analogues (for example water = sans serif italics, land = antiqua all caps, mountains = condensed antiqua bold) can be transferred with appropriate changes.

Thematic mapsExplaining seasons and climate Climate maps are important part of school atlases. We have produced a climatic map of Mars that shows the average temperatures based on solar irradiation (solar climate zones), topographic location (heights / depths), cloud coverage (for mountains) and albedo (dark dunes vs. bright ice caps). On the main map, topographic color coding is also explained as atmospheric pressure change. For the landing sites, where available, we have shown local yearly and diurnal temperature change diagrams, with the explanation of the Ls system. Instead of precipitation data (which always accompany such diagrams) we used pressure and wind data that are available trough one Martian year from the Viking observations. The same diagram shows the yearly change of the distance from the Sun and change in solar irradiation at that particular point (latitude).Contour map. Contour maps are essential for the students’ studies. In the case of the Earth, these maps show the hydrologic system and the borders of continents. Mountains are shown as thick black lines. For other planetary bodies, none of the above can be used: no hydrologic system, no continents, no sea-level, no mountain chains. All planetary bodies has their own characteristic features, while craters are the most common landscape types. For Mars, we have included the north-south boundary, volcanoes as black spots and craters as circles, large valleys as lines, carter-rim-mountains as gray areas. For the Moon, it is the maria, crater-rim-mountains, crater rays, large craters. For Venus, continents, volcanoes, coronae, tesserae, chasmae. Morphologic sketch maps During Astronomy classes at Eötvös University, one of the tasks of the students was to draw the simplified geomorphologic map of various planetary bodies, using topographic, geologic and photomosaic maps. The task included creating a coherent symbol system for their maps (Fig. 7-8). They had a strong background in geography and geomorphology, but not in planetary science. They - naturally - used those symbols they are used to. The result - even if scientifically not correct - has many useful visual and conceptual elements which can be used in drawing simple planetary maps.

Fig. 7. Students explaining their symbol system for Venus. Photo: P. Lovász.

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Fig. 8. A few of the symbols the students used: 1. Volcanic cone 2. Mountain 3. Fossa 4. Dorsa (Venus) 5. Arachnoid 6. Valley (outflow and tectonic).

In the overall appearance, for Mars, they used a white background for highlands and striped background for lowlands - because there are more features inside the highland areas than in lowlands, therefore the map will be clearer this way. These are small but important details. They used the terminology and nomenclature with many errors, since they were not familiar with it. But it was this unfamiliarity which showed exactly the „weak points” of it: they used the word „debris (or ejecta) mountain” for the Lunar circumbasin mountains (Appennines), which exactly describes its nature. They used „Syrtis Major bulge” instead of Planum, “Mariner graben” instead of Valley etc.Data section The World Atlas has a „Geographic Data” section in which the geographic records are shown (longest river etc). We have prepared a dataset of the same structure using planetary records: the largest, highest, longest etc. mountains, valleys, volcanoes, depressions etc. in the Solar System. Paleomaps Since the maps of the Earth show our planet only in a „randomly” selected moment, it can include paleomaps of the Earth, together with estimations of the scales of now-disappeared features of our planet, for proper planetary comparison. If the Earth, Moon, Mars etc. are shown side by side, it can give a good comparative view of the ages of features and planetary surfaces.

EXTRATERRESTRIAL GEOGRAPHIC NAMES

“Individual names chosen for each body should be expressed in the language of origin. Transliteration for various alphabets should be given, but there will be no translation from one language to another. ... Diacritical marks are a necessary part of a

name and will be used. … The number of names chosen for each body should be kept to a minimum, and their placement governed by the requirements of the scientific community.”

IAU Rules on extraterrestrial geographic names (Gazetteer 2003b)Names of extraterrestrial features have almost the same historic complexity as terrestrial ones. „Planetary nomenclature, like terrestrial nomenclature, is used to uniquely identify a feature on the surface of a planet or satellite so that the feature can be easily located, described, and discussed.” (Gazetteer 2003a) While this goal is achieved in scientific discussions, the present form of planetary nomenclature is less suitable for public education or popular science. The IAU nomenclature is in Latin language which is not understandable for a large part of the map readers. Most editors and popular writers - including English speaking ones - do use the local language equivalents of these names together or without the Latin form (in books, articles, Atlases). Since there is no guide for translation, they try their best, and this way produce multiple translated /transcribed /transliterated variants for the same feature name. (N.B. Translation may seem unnecessary for the reader who understand an Indo-European language, since even though the terms are not the same as the corresponding ones in their language, they can find out their meaning relatively easily [Mons - Mount or Planitia - Plains]. This is not the case for several other European and most of non European languages, where the Latin terms are meaningless.)In the case of maps for non-professional or young audience, it might be better - to some extent in contrast to the UNGEN (United Nations Group of Experts on Geographical Names) efforts on a single standardization of geographical names - to use standardized national language variants of the Latin terminology, which would be more adequate (or, this makes possible) to answer the map readers'

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question "What's there" – this way achieving the aims of IAU mentioned above, but extending the target audience to non professionals.

Specific element (proper name) – Names as labels. “The main function of geographical names is to serve as label, and as such, its semantic meaning, even

if evident, is of less consequence than its role as a designation or tag.” (Kadmon, 2000)

Meaning: Since in planetary science the naming is artificial (or, bureaucratic process - except for informal and traditional names), there is no real connection between the proper name and the feature. In some cases there is an indirect connection: they are named after scientists who studied that particular planet, gods of fire for a fiery moon etc, or the connection exist amongst the names of the neighboring features: craters named after Hungarian scientists are in one group on the far side of the Moon). The meaning can be transparent (readily understandable) or opaque. Today usually both element of extraterrestrial names are opaque for all readers who haven’t learned Latin or who are not familiar with the mythology of various cultures (this was not the case when the latin/mithology naming tradition originated). However, for some traditional names both elements are translated, but in spite of this, the name is still remains opaque or, it has “false” (descriptive) generic, which does not describe the feature, and also false specific considering its meaning (Sea of Rains). Here the geologic term would be better understandable (Imbrium Basin), but this has a different meaning in geology (the original crater). While the meaning itself is of secondary or no importance in scientific publications, for the general public, the meaning or its historic connections can be more important (or just interesting). This argues for the restoration of the original meaning in the local language, while if we consider its label function, this argues against any attempt of translation or even transcription / transliteration of the names. A traditional exception is if the specific element contains compass points (a current example is how to translate “South Pole - Aitken Basin” usually referred to as “SPA” - which is not an official IAU name).

Non-official specifics or names Astronaut- or mission geologists-named features of the Moon and “named stones” on Mars are somewhat “off” the nomenclature, since it neither follows the IAU rules of naming features, nor the terms used for lunar features. But, in fact, it is the only case, when the features get their name by natural naming process; therefore the names are related to the characteristics of the named object and / or to those who named it. The rule here usually is that they be easy to remember, they should not be names of real people and they should not be derogatory (Morton 2002:234). Since by now these names are all given by Americans, the terms are in English (Mountain, Massif) and the specific elements are in English and in many cases are taken from the American culture (Snoopy, Scooby Doo, Zaphod, Photometry Flats, Family Mountain, North Massif). Here, the same rules apply as for terrestrial maps – which let open the question whether to translate one or both elements of the name. In practice, the generic is usually translated, the specific only rarely, and sometimes both are kept in their original form. Widely used informal names on the Moon are Cap Banat, Great Wall, Cobra Head, on Mars: Inka City, Happy Face crater, Giant’s Footsteps etc. Since most observers do use these names, it is clear that a map should also display these „naturally created”, but not official names. These should be given in the target language – here the meaning is more important than the labeling function, – not in an artificially latinized form. In some cases the same feature has Russian and “International” (=IAU) names parallelly. Such examples are some catenae on the far side of the Moon, where both names are shown on our maps. It might also be interesting for the map user to display some of the historic names (Hourglass see, Nix Olympica) which can still be found in science history related texts.

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Descriptive elements (generic element, generic term or – in IAU definitions – descriptor term) The system of most Latin descriptive elements was first developed by IAU and USGS astrogeologists for Mars in 1973 in Sydney. Usually the IAU descriptive elements are true ones concerning their meaning (as far as our current knowledge makes it possible); The meaning refers to the topographic nature of the feature and does not reflect its geology or formation. This is good method when we have no good theories concerning the real nature of the feature. (a classical example is the word “crater”, which is used both for impact and volcanic structures, which, in some cases, really have very similar morphology.) When translated, it might be advisable to translate them using existing geographic descriptive elements in the target language that also reflect its formation or geology. There are also some intentionally (traditionally) false descriptor terms for some lunar features (Lacus, Mare, Palus, Sinus). The translation of both elements in this case is traditional, however, this makes lunar nomenclature also false in the target language. Such names on Mars had existed but has been renamed. After translation, the same Latin term can refer to various geologic landforms: Planitia, for example, can mean (impact) basins and (sediment-filled) plains as well. In some cases 1) the generic Latin term has terrestrial parallel term, in other cases 2) it can be directly translated from Latin, or 3) it can be kept in the original form, but transcribed/transliterated to the target language. However, in some cases the descriptor term is somewhat misleading concerning the geology: Farrum, farra is defined as “Pancake-like structure, or a row of such structures” – while the structures of the same morphology are named Tholus, tholi (on Io). The same way tholi and paterae usually refer to shallow volcanic calderas (with or without cone, respectively), while calderas on high volcanoes are not named. Mons, montes are impact basin rims on the Moon and Mars while smaller craters rims are not named. The same way basins (Planitiae) are large impact craters - but where is the threshold between basins and craters? Mons, Montes on Venus and Io are however of different origin, having no relation to impact processes. Corona, coronae are “Ovoid-shaped features”, but these are of different nature on Venus and on Miranda. Venusian coronae have many types - arachnoid, nova, corona - that are used in geology. An unusual part of planetary nomenclature is the Moon, where – in contrast with its former nomenclature and the current Martian nomenclature – there are no regional names assigned for the highland regions: no terrae on the Moon (although there used to be). Thus, the highest hierarchic level is missing on this part of the moon (most of the far side). Large scale features are not well defined on other planets as well: „The boundaries of many large features (such as terrae, regiones, planitiae, and plana) are not topographically or geomorphically distinct; the coordinates of these features are identified from an arbitrarily chosen center point. Boundaries (and thus coordinates) may be determined more accurately from geochemical and geophysical data obtained by future missions.” (Gazetteer 2003c) This is also true for Earth, but with much less “uncertainty-zone”. This might help defining Lunar regional named features as well. NB: Undersea features names - resulting from the same internationally standardized artificial naming conventions - are usually translated to the target language in maps, both their generic and specific elements. For translation method, here I propose to keep the labeling function (avoiding more chaos) of the specific element, which, as for its meaning, usually has little reference to the feature itself (no Blue Mountain on Mars - yet), while the generic element (term) should be made transparent, since it does have reference to the characteristics of the feature.

Local versions – Endonyms These are local names for local features. Some extraterrestrial names are based on (named after) terrestrial geographical features, but of course are not endonyms. They usually

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use their latinized or “international” (i.e. English) form. Even Greek personal names or Gods are latinized. An example for an exception is Io, where, instead of a neutral Latin form, IAU used the English exomym of many geographic names (Danube, Ionian (sea)) which can not be argued for. It makes more difficult to find out which version to use: the English exonym or the local endonym of the same feature. As label, it should be the English one, but as a geographic name, for many languages, it has an endonym or an other form of exonym (in this case, in Hungarian: Duna and Jón). If the terrestrial “donor” feature is located in the area of the target language, they usually traditionally use that form (local endonyms of the Carpathians instead of Carpatus Montes). It is an open question whether to extend the rule of using the endonyms or exonyms for other toponyms that has no such tradition (example: Danube Planum on Io).

Exonyms These are name used in a specific language for a geographical feature outside the area where the language has official status. Extraterrestrial examples are the valley names of Mars, where they are endonyms of terrestrial rivers in various languages (Latin, Arab). These should not be translated to the target language’s existing exonym form because it would loose its label function. Most extraterrestrial names are neither endo-, or exonyms: they are standardized, artificial international names. However, some names have become exonymes for most languages during the last centuries. Such are the maria of the Moon and the most prominent features of Mars (here exonyms are in fact historic or mythological exonyms). These can be kept in its traditional form, where all elements are translated (on the Moon), or, replaced with the standard non-translating method (on the Moon then Mare Imbrium would become Imbrium Basin (as if it were Imbrium Planitia), which 1) sounds alien for most astronomers, 2) are used for the unfilled basin in geology 3) but best fits a standardized nomenclature.)

Classical names - a poetic argument The so called “Classical albedo features” (Mars, Mercury) which have been used – although differently – well before the IAU, and are used extensively by amateur astronomers, – bring up an other question: should we use the local (exonym?) versions of these mythological names (in many cases, only transcripted or transliterated: i.e. with more accents) or we’d better drop the traditional mythical form and we consider these names again as labels and keep the latinized form. This way many names would become opaque; while if we would apply the necessary (slight) changes, the original “poetic” meaning – that had an important role in popularizing Mars in the 19th Century – would be restored. Schiaparelli established the “rule” of giving mythological names for landforms, which became very popular and, may be more importantly, easily remembered by the educated people of that century. He copied the Greek (mythological) map of the Mediterranean transferring it to Mars, using some associative thinking. At that time it also was a common practice to show names on the map in Latin form: Mare Germanicum etc. So, at that time, his Latin nomenclature perfectly fit into the terrestrial nomenclature system and were all transparent to their readers. Our goal is that at least partly, this “sense” of names be re-established in their modern form. (of course, in international scientific articles, strictly only the original IAU nomenclature should be used).

Transformation without translation We have to options: 1) Transcription: phonetic transformation of a name. (for non-roman alphabets). Usually the original form can not be restored from the transcribed one. 2) Transliteration: transformation letter by letter, where the original form can be restored from the transcribed one. While international single romanization methods (Russian, Chinese Pinyin) makes international trading, international scientific discussions and mapmaking much easier (or, making it possible), the transliterated names using these rules 1) do not fit to the various languages own system,

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2) look alien to many (contain letters that are not used in some languages) and 3) usually are hard (or impossible) to pronounce for those who are not familiar with the romanization principles (e.g. most people) – not because they could not pronounce the sound, but because they don’t know how to read/interpret the particular letter. Most languages has their own transliteration or transcription rules from non-roman alphabets which do fit the given languages character. I propose that – for locally and not internationally used products – at least for the most frequently used names, on the maps and texts, we do show the forms created by using local rules in addition to the international ones. In Hungary, some terrestrial maps use the international romanization while others use the local method defined by the Hungarian Academy of Sciences, so the question remains to be open even for terrestrial maps.

Orthography All extraterrestrial geographic names follow the Latin (and English) tradition: they are composite names which the first letters are capitalized and the elements written separately (except for craters and ephemeral features, which have no generic). However, geographic names in some languages have different rules. Hungarian, for example, uses a hyphen between the two element, and the generic term is written without initial capital letter. So, the local language rules should be applied when “localizing” extraterrestrial maps.

Bilingual or biscriptural maps – Extraterrestrial allonyms Allonyms are alternative names: several toponym for the same feature. These can be shown in a multi- or bilingual gazetteer and/or multilingual / multiscriptual maps. For maps, space is a limiting factor, so only the most prominent features should be written in two languages/scripts (one is the target language, the other is the international form). Craters, fortunately, have no generic element. In the case of craters named after words/names originally written in Cyrillic letters, on our test map we always displayed the original Cyrillic form as well. This can only be done if the most of the target audience at the date of publication can read that alphabet (today this changes very rapidly in the case of Hungary). But the other way, for nations using a non-roman alphabet, they can display both local and the official Latin form.

Changes in the nomenclature As place names of Earth change, because of history, place names change on other planets, too – because of standardization, history and – more importantly – scientific considerations. Planetary nomenclature has been cleared and standardized by IAU, for the Moon in 1935, and for Mars in 1958 and 1973 (Greeley and Batson, 1990). During the discovery (mapping) of a celestial body, new names (naming rules) and – if needed – terms are created (Titan is expected to go through this process in these years). If a more detailed image shows that a feature have been misinterpreted, its generic element is changed (example: Anala Corona -> Anala Mons or Cerberus Rupes -> Cerberus Fossae) Other features’ names are dropped because they turned out to be only part of an other feature or to be nonexistent during the revision of the images. We are aware of the fact that not only the names, but also the methods of transforming/translating geographical names change in time or there can be parallel schools which use different methods, as it is the case in the cartographer community in Hungary. Now there seems to be a need for more “Hungarian-sounding” names in contrast to “foreign-sounding” ones but this might be only the latest (or local) fashion we live in.

Case study - Hungary. In Hungary, the rules for how to write planetary feature names are not established. For major planetary bodies, the previous chaos was cleared by the rules in the 1970s that stated that names of planets should be written according to their pronunciation (Vénusz instead of the formerly used Venus). However, there was no rules defined for names of moons, asteroids and planetary features. Now names of minor planets are written in the official IAU form, i.e. in the

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Latinized form, may be because the use of language has changed: now the Latin original seems more appropriate for moons and asteroids - at least, for the planetary scientists who are used to these forms. But not necessarily for the young students or the general public: in many publications in Hungary (usually translated books from English) the names of Jovian moons are translated, using the locally traditional name of the particular God (Europa: Europé, Ganymede: Ganümédész etc.). We may try to keep as many names as possible in Latin forms, but also keeping the widely used traditionally translated or exonym forms. It is also possible - in oral reference- to avoid the use the generics where possible: to refer to landforms as “Hellas” or “Ascraeus” adding the geologic term of the feature (basin, volcano).

Future nomenclature Several scientific paper discuss unnamed features, identified by their coordinates. For the yet unvisited worlds the presently known albedo features are – in most cases – not named (Pluto, Charon). In the future probably many new feature will be named (this time in the Saturn system), new terms will be used and new planetary bodies get their nomenclature system. Especially after such discoveries, new names come out easily and fast (as were the case when discovering the far side of the Moon) which are off the IAU rules: Circus Maximus is the latest one (Titan). With new landings, rover missions, naturally created names will appear in great numbers. There is an urgent need for a general guide of how to translate these names to other languages in a controlled or standardized way, for the daily press and popular science papers.

CONCLUSIONSIn the case of publishing planetary maps for a non-expert readership, it is proposed to use common (latinized or internationally romanized) specifics (without translation) and separate (translated or transcribed/transliterated) generics for different languages, as in the case of many undersea features. The specific elements should never be translated, except for those features that has a traditionally translated variant. It is also recommended to show – as available space makes it possible – a bilingual (international and local) nomenclature on planetary maps, especially in the case of names with translated specific elements.The visual appearance, symbol system and the contents of planetary maps should be closer to terrestrial maps making them easier to interpret correctly. Comments and height data appearing on the map can also help to improve its understandability. Thus the reader can form a more realistic mental map of the particular planetary body.

REFERENCESAlmár I. (2005): Terminology: a Bridge Between Space and Society. First IAA International Conference

Impact of Space on Society. BudapestGazetteer of Planetary Nomenclature (2003a) http://planetarynames.wr.usgs.gov/preface.html (accessed 1.

Oct. 2003., Last updated: 01/31/2003)Gazetteer of Planetary Nomenclature (2003c) – Naming Conventions http://planetarynames.wr.usgs.gov/,

(accessed 1. Oct. 2003.)Gazetteer of Planetary Nomenclature (2003b) http://planetarynames.wr.usgs.gov/ (accessed 1. Oct. 2003., Last

updated: 01/31/2003)Greley R. and Batson R. M (1990) Planetary Mapping. Cambridge Univ. Press H. Hargitai, J. Lazányi, Á. Kereszturi (2003-2004): Astronomy chapter of the World Atlas in:. Földrajzi

Világatlasz (World Atlas), Topográf Publishing Co., Budapest Hargitai H. I., Rükl A., Roša D., Kundera T., Marjanac T., Ozimkowsky W., Peneva E., Oreshina L. S., Baeva

L. Y, Krasnopevtseva B. V, Shingareva K. B. (2003).: Multilingual map of the Moon. MIIGAiK-Eötvös University, Cosmic Materials Space Research Group

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Hartmann W. K (2003): A traveler’s guide to Mars. Workman, p 330.Kadmon, Naftali (2000). Toponymy. Vantage Press, New York, 2000. p 37Morton, O. (2002): Mapping Mars. Picador, New York. USGS (2004) USGS Astrogeology: Selected Planetary Geology Features http://astrogeology.usgs.gov\

Projects\ PlanetaryMapping\Mapsymbols\geofeatures.htm (accessed 16 Feb 2004)

ACKNOWLEDGEMENTSThe Multilingual map series were supported by ICA Commission on Planetary Cartography. We are grateful for the help of Prof. Kira Shingareva who initiated the multilingual map series. The publication of the maps of Venus, the Moon and Mercury (Central European Edition) were supported by the Hungarian Space Office.

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