RECORD_TYPE = STREAM PRODUCT_CREATION_TIME = 1999-03-01 OBJECT = TEXT NOTE = "Introduction to this CD volume." END_OBJECT = TEXT END Mission to Mars This compact optical disk (CD) is one of a series of CD 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). Volume Series Contents Volumes 1- 6: Global Coverage of Black/White MDIMs at 1/256-th degree/pixel. (231 meters/pixel) Volume 7: Global Coverage of Digital Terrain Model (DTM) and Black/White MDIMs at 1/64-th degree/pixel. (925 meters/pixel) Volumes 8-13: Multi-look Color MDIMs at 1/64-th degree/pixel. Volumes contain multiple color views of the Martian surface. Planet wide coverage is incomplete. Volume 14: Multi-look Color MDIMs at 1/64-th degree/pixel. Volumes contain 8-bit color images in a GIF format. Data have been pre-stretched for optimal color display. The CompuServe Graphics Interchange Format (GIF) is commonly used to upload documents and graphics to the CompuServe Information Service, and to pass graphics between computers. Volumes 15-22: High Resolution Coverage of available Black/White MDIMs at 1/1024-th degree/pixel. (approx. 58 meters/pixel) 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 volume in a format that is designed for access by computers. Another file may exist, ERRATA.TXT, describing possible problems with the CD. 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. It is recommended that you read the VOLINFO.TXT document before trying to process image files. The directory named INDEX contains the image index files for the volume series. This table has descriptive information about the images on this volume. 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 label file contain information about this index table. NASAView Image display software for viewing the MDIMs can be obtained by visiting the PDS software page at: http://pds.jpl.nasa.gov/ . When using NASAView, keep in mind that the images have not been optimally pre-stretched. It is important to use a contrast stretch in NASAView by using the Image/Stretch Display option to display the images properly. With no stretch applied, the images will often appear a solid gray color. 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 much 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, with production of CD products funded by NASA's Planetary Data System. NASA's Planetary Data System also provided the guidance and standards required to manufacture and distribute the optical disks containing this MDIM of Mars.