CCSD3ZF0000100000001NJPL3IF0PDS200000001 = SFDU_LABEL RECORD_TYPE = STREAM PRODUCT_CREATION_TIME = 1992-02-01 OBJECT = TEXT NOTE = "Introduction to this CD-ROM volume." END_OBJECT = TEXT END Mission to Mars Mars Digital Terrain Model and Mosaicked Digital Image Model (MDIM) This compact read-only optical disk (CD-ROM) is one of a series of seven CD-ROM volumes containing cartographic compilations made by processing "raw" Viking images to reduce radiometric and geometric distortions and to form geodetically controlled Mosaicked Digital Image Models (MDIMs). Volumes 1 through 6 contain MDIMs at 1/256, 1/64 degrees/pixel and Airbrush Digital Shaded relief images at 1/16 and 1/4 degrees/pixel. Volumes 1 and 6 contain MDIMs at 1/16 degrees/pixel. Volume 7 contains planet wide coverage of MDIMs and Digital Terrain Models (DTMs) at 1/64 and 1/16 degrees/pixel. The registration between the DTM and MDIM compliations are typically within 1 or 2 pixels for most of the planet coverage. This file is one of only a few files located in the main directory. The VOLDESC.SFD file contains a description of the contents of this CD-ROM volume in a format that is designed for access by computers. Another file may exist, ERRATA.TXT, describing possible problems with the CDROM. If it exists, then it includes instructions for resolving these problems. The directory named DOCUMENT contains a text file named VOLINFO.TXT that describes in detail the organization of this disk and the format and content of the MDIMs and DTMs. It is recommended that you read the VOLINFO.TXT document before trying to process image files. The directory named INDEX contains the file DTMINDEX.TAB. This table has descriptive information about the images on this volume (in DTMINDEX.TAB). The index table are text files in a format that can be read by people and computers. The tables have been designed so that they can be loaded into most database systems for fast and efficient searching. The VOLINFO.TXT file and the DTMINDEX.LBL files contain information about this index table. Within the SOFTWARE directory are subdirectories for the Sun, PC, Macintosh, and VAX platforms. These subdirectories contain executable versions of image display software. The file SOFTINFO.TXT in the MAC, PC, SUN, and VAX subdirectories describes the software for each platform in detail. Most files on this disk have a label encoded in the Object Description Language (ODL) developed by the Planetary Data System (PDS). An ODL label is readable by both humans and computers. It provides a formal description of the format and content of a file. For most files the ODL label appears at the beginning of the file (as is the case for this file). All image files have an embedded ODL label preceding the data in the file. For files where labels cannot be easily included, a separate file is provided that contains the ODL label. A pointer in the label file indicates which file the label describes. External label files have a '.LBL' extension. For a description of the Object Description Language, see the document file VOLINFO.TXT in the DOCUMENT directory. The LABEL directory contains ancillary labels in ODL format that describe the additional structural information about the image files. The National Aeronautics and Space Administration is charged with the responsibility for coordination of a program of systematic exploration of the planets by U.S. spacecraft. To this end, it finances spaceflight missions and data analysis and research programs administered and performed by numerous institutions. The Geological Survey of the U.S. Department of the Interior is the agency that performs most of the mapping in support of NASA's program of planetary exploration and scientific research. The digital Mars maps contained in these volumes were compiled by the U.S. Geological Survey (USGS) under funding provided by NASA through its Geology and Geophysics Program at NASA headquarters, Washington, DC, and through the Mars Observer Project administered by the Jet Propulsion Laboratory, Pasadena, California. NASA's Planetary Data System provided the guidance and standards required to manufacture and distribute the optical disks containing this MDIM and DTM of Mars. Compilation of the Mars digital models was performed at USGS under the direction of R.M. Batson, L.A. Soderblom, and Sherman S.C. Wu, Principal Investigator and Co-Investigators, respectively. Wu provided the technical management and supervision of a team of photogrammetrists who compiled the topographic control and the topographic maps used to make the DTM. Kathleen Edwards provided the technical management and supervision of a team of technicians who compiled the MDIM. The design, layout, and production of the CDROMs were performed by E.M. Eliason, A. Manley, and A. Allison at the USGS, and M. Martin and J. Hyon at JPL.