PIMAP AS A TOOL FOR CARTOGRAPHIC REPRESENTATION OF THE "CATALOG OF LARGE MARTIAN IMPACT CRATERS"
S. Gehrke1, R. Koehring1, N.G. Barlow2
1 - Technische Universitaet Berlin, Geodesy and Geoinformation Science, Berlin, Germany
2 - Northern Arizona University, Department of Physics and Astronomy, Flagstaff, Arizona
The cartographic software package Planetary Image Mapper (PIMap) has been developed for the generation of the Topographic Image Map Mars 1:200,000. This large-scale map series is the cartographic standard product of the Mars Express mission, covering the Martian surface in 10,372 individual sheets. Each sheet is based on High Resolution Stereo Camera (HRSC) images and Digital Terrain Models for contour line derivation; it is supplemented with graticules, topographic names (craters, mountains, valleys, etc.), map titles, and further marginal information. The entire map content can be generated and/or compiled using PIMap.
The Catalog of Large Martian Impact Craters (henceforth Catalog) provides information on 42,283 craters with minimum diameters of 5 km, such as, size, shape, preservation, morphology, and ejecta properties. Compared to this, a rather small number, 922 craters of all diameters, has been given names so far. While the latter craters are labeled in various maps, the Catalog data are not represented in almost all cases except for few special products. However, the large-scale Topographic Image Map Mars 1:200,000 series allows for the integration of such a huge data set; once the ongoing revision of the Catalog is completed (version 2.0), crater IDs will be included.
In order to automate this part of map generation, PIMap is currently upgraded. Thus, the Catalog has to be matched with the USGS Gazetteer of Planetary Nomenclature, which provides names and locations of all natural surface features for all celestial bodies and, therefore, is the current basis for labeling in PIMap. Technically, the entire information of both data bases is merged and mirrored into a system of C++ classes. Based on the respective class “MarsCrater”, impact craters can be labeled in topographic maps with their names and/or Catalog IDs, which are composed of latitude and longitude. With regard to automation of thematic mapping it is conceivable to integrate, e.g., crater outlines, depths, or central peak heights in the map surface and, depending on the user’s definitions, to give additional information in tabular form within the legend.
In conclusion, additional benefit of the new Topographic Image Map Mars 1:200,000 series results from becoming a cartographic representation of the Catalog, i.e. the provision of the scientific community with the link between appearances and locations of impact craters and a huge set of further information. Beyond the generation of standard map sheets, the cartographic software package PIMap can be used as general visualization tool of the Catalog.