Don't watch this space

The NASA Atlas of the Solar System

九月 12, 1997

An ambitious title and an ambitious undertaking, this book aims to bring together maps of all the solid bodies of the Solar System so far explored, in a uniform format and at a standard scale of 1:10,000,000 for most. Unfortunately, the number of errors in the final product, some of them major, indicate that it has been a little too ambitious. "Producing the atlas has been a tremendous effort that has involved the contributions of a great many people," declare the authors in the preface, and indeed the list of people contributing reads like a Who's Who of top planetary scientists and cartographers. It is aimed at both planetary scientists and those interested in Solar System exploration on a more casual basis. The book is of large format (45 x 31cm), is solidly constructed, and falls open easily, so that the maps can be worked on comfortably. As well as shaded relief maps and computer seamless photomosaics, many of them in colour, Ron Greeley has ensured that there is also a geological map to go with almost every single planet and satellite, however small. There is also a representative selection of the best original spacecraft images of each body, and an introductory text to each, plus a history of its cartography and present knowledge of its surface features and geological processes. This kind of book is always in danger of being upstaged by the next planetary mission; in this case, the most recent Galileo images of the Galilean satellites of Jupiter came too late to be included.

To start with the good points, there are some spectacular maps in this atlas, the best by far being the beautiful computer photomosaics of Mars, showing the surface in the tiniest detail, and with unobtrusive latitude and longitude markings too. That of Neptune's moon Triton is similarly impressive. The synthetic aperture radar mosaic maps of Venus are not so clear or easy to use, and the photomosaics of Io are of degraded resolution. There is no photomosaic of the Earth.

The airbrush maps are a useful adjunct to the mosaics, particularly for Venus, where the topography is far clearer than in the SAR photomosaic. There are some unavoidable problems of presentation owing to the attempt to print most of the maps at the same scale; some are enlarged too much, notably Saturn's satellite, Mimas. Nonetheless, it is extremely useful to have maps of all the explored Solar System bodies within one volume.

In dealing with the less admirable qualities of this atlas, it is charitable to assume that the 14 distinguished scientific reviewers did not see the final version, as it bears all the hallmarks of being assembled in far too much of a hurry. Putting myself in the position of someone new to the science, I found myself feeling less and less well-disposed towards the production team as more and more misprints, mistakes and confusions came to light. On pages 98-104 we learn that the bottom of the deepest oceans on Earth are 6,000 metres up in the air, and that the highest mountains are in fact 4,000 to 6,000 metres below sea level (the colour key is upside down). The scales for the same maps, and all those for the planet Venus, are also wrong (in fact unusable) in every case, as values are incorrect and there is no zero. One also has to search very hard to find what map projection is being used, and how distortions affect the scale given (this information is given in one place only in the book). Half the titles of almost all the maps have been accidentally missed out, so that one never knows if one is looking at a shaded relief map, topographic map or photomosaic, and a map of Neptune's satellite Triton is erroneously presented as Titania, a satellite of Uranus, on pages 304-305. Latitudes and longitudes are also wildly wrong on several maps. Although an "index" map is given for each series of planetary maps, page numbers and type of map are omitted, and for Mars, the shaded relief maps have different boundaries, and in some cases different names, from the photomosaics, so that the index map is incorrect for the latter. Only by referring back to the table of contents at the start of the book can some of the confusion be sorted out, yet even here there are errors, some photomosaics being described as shaded relief maps. To the initiated it is fairly obvious what has gone wrong, but this sort of thing can be totally confusing and time wasting to the student or schoolchild, and really should have been picked up in proof stage.

The geological maps, though again a potentially very useful collection, list units and stratigraphical relations without any explanation, or in contradiction to the text. The geological map of Io, for example, lists no fewer than nine different units under "flow materials": fissure, breakout, hummocky, patera, lobate, plains-forming, tholus, shield and undivided. None is described, and only fissure eruption, patera and shield volcano are listed in the glossary. Referring to the text, we find that none of these categories except shields is even mentioned, but other kinds of flows are: sinuous flows, sheetlike flows etc, which do not appear on the map. The reader is left confused and in ignorance as to the significance of the mapped units and their relation, if any, to the geological history of the planet.

Unfortunately, there are similar signs of hurried production in the text and picture captions. The word "photograph" is often used when "image", "picture" or "photomosaic" is meant. This is the kind of distinction that might not mean much to the general public, but when trying to drum the importance of different imaging systems into students and sixth-formers who are eager to learn, it is extremely irritating to find such elementary errors in a book that has the full endorsement of Nasa. There is no clear indication of what a synthetic aperture radar image is, and how differently they should be interpreted from ordinary images. The term does not appear in the glossary, which again seems to have been given little thought. The glossary includes such entries as astronomy, rock, atmosphere, full moon, soft landing etc, which are either universally understood or self-explanatory, yet real technical terms such as triaxial ellipsoid, protosolar, shepherd satellites and caldera, which occur again and again in the text, are omitted. I found many other mistakes and misprints, including historical details, sizes and so on.

Finally, the 40-page gazetteer of named features on all the Solar System solid bodies would be an extremely useful reference list, but in this case they have forgotten to say what each one actually is. Some 5,000 features are meticulously listed, with geographical coordinates and sizes, but without any indication whether each listed item is a crater, mountain, plain, or one of the host of other types of landform included. Some of these, such as Rima Galilei, Deuteronilus Mensae and Gipul Catena, will be obvious to those in the know, but ... you have guessed it: Rima, Mensae and Catena are not in the glossary, nor the index.

I think you get the picture by now. Briefly, this has the makings of an excellent and useful atlas, but is ruined by silly mistakes and sloppy production that are worthy of the pedigree of neither authors, contributors nor publisher. An atlas is a work of reference, and while the occasional misprint is unavoidable, this volume really requires another six months spent on it, and needs to be given a thorough going over by someone with a meticulous disposition who is familiar with the history, science and cartography of planetology. At Pounds 100 a copy I would wait until things have been sorted out and a reprint is issued before buying.

John B. Murray is research scientist, the Open University.

The NASA Atlas of the Solar System

Author - Ronald Greeley and Raymond Batson
ISBN - 0 521 561 2
Publisher - Cambridge University Press
Price - £100.00
Pages - 369

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