1. Introduction This data set has been generated by the Jet Propulsion Laboratory's (JPL) Science Digital Data Preservation Task (SDDPT) by migrating valuable space science data from older, deteriorating magnetic tapes to CD-ROM. The primary goal of the SDDPT is to reduce the amount of data stored on magnetic tapes, preserve valuable science data and make it more accessible to the user. This data set resides on a series of CD-ROM volumes containing image data. The first volume in the set also includes ancillary information in addition to image data. The input for the compact disc was magnetic tape which, in most cases, was at least 15-20 years old. Accompanying each data file on the disc, there is a log file which documents SDDPT processing history. Therefore, if problems were encountered while recovering the data from tape, they will be documented in the log file. The SDDPT is not reformatting the data. However, it has been make readable in standard ISO 9660 format on the compact disc useable on a variety of platforms. Three copies of each title will be generated: one for deep archive at the National Space Science Data Center in Goddard, MD; one as a backup copy at the JPL Archives; and one to reside with the data user. In the cases where a planetary data set is likely to have many users, the "user" disc will be sent to the cognizant discipline node of the Planetary Data System. For further information about the SDDPT and the process by which valuable data sets were identified, see the SDDPT Inventory/Evaluation Phase Final Report,(JPL Document D-10753) or contact: Amy Hochstettler Culver MS 168-514 Jet Propulsion Laboratory 4800 Oak Grove Drive Pasadena, CA 91109 818-354-4432 Electronic mail addresses: SPAN: MIPL3::ADH875 Internet: ADH875@ipl.jpl.nasa.gov 2. Data Set Information The Mariner 10 spacecraft gathered images of Earth's Moon, Venus, and Mercury, in addition to star calibration and other test data. The wide-angle and narrow angle cameras on the Mariner 10 spacecraft formatted the images into arrays 832 pixels by 700 lines. Each picture element (pixel) in the two dimensional image array is represented as an 8-bit value between 0 and 255, proportional to the amount of light detected at that point (with 0 being the least amount of light and 255 being the greatest amount of light). To make full scientific use of the image collection, the radiometric and geometric properties of the camera system should be understood. Currently the electronic Mariner 10 calibration data resides on a series of 7 track tapes with the prefix "VM". During the course of the SDDPT, those tapes will also be archived onto CD-ROMs and subsequently added to this volume set. The collection consists of Mariner 10 images retrieved from Archive Experiment Data Record (EDR) magnetic tapes created during the Planetary Image Conversion Task (PICT) conducted at JPL from 1983-1985. Each Mariner 10 image file consists of 22 blocks containing 31,944 bytes per block. Eack block is composed of 33 logical records of 968 bytes each. The first logical record of the first block contains a single set of VICAR label information. The tapes were created on an IBM system, so the VICAR Standard Format labels are written in EBCDIC. The labels are followed by 700 logical records (one per image line) containing pixel data and engineering data. The data contents of the labels and engineering data are provided in the "Planetary Image Conversion Task Final Report." Documents which may be useful in interpreting the Mariner 10 data set include, but are not limited to: Martin, Michael, et al., "Planetary Image Conversion Task Final Report" (JPL Publication 85-50, September 15,1985.) Davies, Mert, et al., "Atlas of Mercury," NASA SP 423, 1978. "Mariner Venus Mercury 1973 Project Final Report, Volume 1: Venus and Mercury Encounters," Technical Memorandum 33-734, September 15, 1976. "Mariner Venus Mercury 1973 Project Final Report, Volume 2: Mercury 2 and 3 Encounters," Technical Memorandum 33-734, December 1, 1975. "Mariner Venus Mercury 1973 Mission and Test Computing System Facility Capability Description of System Test, Appendix E: Data Record Formats," JPL Internal Document 615-43, Jet Propulsion Laboratory, Pasadena, California, August 1, 1973. The images in this collection are fully described in the Planetary Image Conversion Task (PICT) Final Report. The document includes background and rationale for the PICT. It also gives an overview of the image data sets; historical storage and access procedures; and describes how the conversion and data recovery processing were performed. A summary of task results is provided, with recommendations for the disposition of new tapes generated by the task. The appendicies to the task report contain: descriptions of the new archive data set; brief descriptions of imaging instruments, data records and catalogs as reference material; conversion processing details; a summary of unrecovered data; and a complete index of image identifiers and archive tape and file numbers. During the PICT, when multiple versions of an image existed on the input tapes, they were archived as individual files in multiple locations on the output tapes. In order for the user to determine whether multiple versions of a single image appear in the archive, and which of those versions is of the best quality, an indexed file, MVE_INFO is included on MVM_0001, the first disc in the series which contains ancillary information. In MVE_INFO, each image is listed by its identifying FDS count, the original tape and file numbers are given which enable the user to locate the data on the original tape. Brief comments about the quality of the image are provided, noting missing lines as applicable. In order for the user to locate a file on the appropriate CD-ROM volume, he or she must check the jewel box backliners to determine the input tapes used to create the CD-ROM. To simiplify this process in the future, an indexed file including the FDS count, tape ID and archive CD-ROM volume will be included on the last disc of the series. Each of the remaining volumes in the set contains images stored as VICAR files. The files were originaly written on an IBM, so the VICAR labels are stored in EBCDIC. If the data is to be utilized on an ASCII platform, the labels and the image data must be translated. 3. Disc Format Each CD-ROM disc has been formatted so that a variety of computer systems (e.g. IBM PC, Macintosh, Sun, VAX) may access the data. Specifically, the discs are formatted according to the ISO 9660 level 1 Interchange Standard, and file attributes are specified by Extended Attribute Records (XARs). For computer software that fully supports XARs, access to the CD-ROM volume will be straightforward; the disc will appear to the user to be identical to a file system of directories, subdirectories and data files. Some computer systems that do not support XARs will ignore them; others will append the XAR to the beginning of the file, in which case the user must read past the first 512 bytes of the file. For further information, refer to the ISO 9660 Standard Document: RF# ISO 9660-1998, 15 April 1988. 4. CD-ROM Contents The files on this CD-ROM are organized in one top-level directory with several subdirectories. The following table shows the structure and contents of these directories. In the table, directory names are enclosed in square brackets ([]), upper-case letters indicate an actual directory or filename and lower-case letters indicate the general form of the directory file names. Top-level directory | |-AAREADME.TXT - A text file containing general information. | |-[INDEX] - Directory containing an index file to simplify searching for | | specific images. | | | |-MVE_INFO.TAB - A text file describing basic information about | | each image. In this file, image identifiers (FDS | | counts) are correlated with tape and file numbers. | | A brief description noting the image quality and | | missing lines is also included. On the last CD in the series, | | the CD volumes will also be listed. | | |-[MVE_xxx] - The image data files are arranged into directories based on | | the INPUT TAPE IDS. The user can locate a particular image | | file location on the original tape by using the | | MVE_INFO.TAB file. | | | |-[IMAGES] - The subdirectory containing the data files. | | | | | |- MVE_xxx.yyy;1 - Each image data file has a unique name. The file | | name (MVE_xxx) represents the input tape id, and the file | | extension (yyy) indicates the file number on the input tape. | | Example: MVE_007.95 is the file originally located on | | tape MVE_007, file 95. | | | |-[LOGS] - The subdirectory containing log files describing tape copying | | | history. | | | | | |- COPY_LOG.yyy;1 - The tape copying history has been preserved for | | each image data file so that the user can determine if some | | data has been skipped or lost due to problems reading the | | input tape. There will be a COPY_LOG in the directory covering | | each file on the input tape. If there is only one log file in | | the directory, it covers all files on the tape, otherwise the | | file extension (yyy) indicates the file number on the input | | tape. If problems were encountered during the copying process, | | the entire history will be preserved in this log file. | | 5. Text Files and Tabular Files All document files, copying logs and descriptive files for the tabular indexed files contain a carriage return character (ASCII 13) and a line feed character (ASCII 10) at the end of each record. This allows the files to be read by the MacOS, DOS, Unix, and VMS operating systems. Tabular files are formatted so that they may be read directly into many database management systems on various computers. All fields are separated by commas, and character fields are enclosed in double quotation marks ("). Character fields are left justified, and numeric fields are right justified. The "start byte" and "bytes" values listed in the labels do not include the commas between fields or the quotation marks surrounding character fields. The records are of fixed length, and the last two bytes of each record contain the ASCII carriage return and line feed characters. This allows a table to be treated as a fixed length record file on computers that support this file type and as a normal text file on other computers. 6. Recommended CD-ROM Drives and Driver Software (Note that the following list is not inclusive.) VAX/VMS Drive: Digital Equipment Corporation (DEC) RRD40, RRD42, or RRD50. Driver: DEC VFS CD-ROM driver V4.7 or V5.2 and up. Note: The driver software may be obtained from Jason Hyon at JPL (Files are: JPLPDS::DISK$USER1:[JHYON]VFS*.A). It is necessary to use this driver to access the XARs on the CD-ROM. VAX/Ultrix Drive: DEC RRD40, RRD42, or RRD50. Driver: Supplied with Ultrix 3.1. Note: Use the "cdio" software package (in "~ftp/src/cdio.shar" from the "space.mit.edu" server). IBM PC Drive: Toshiba, Hitachi, Sony, or compatible. Driver: Microsoft MSCDEX version 2.2. Note: The newest version of MSCDEX (released in February 1990) is generally available. Apple Macintosh Drive: Apple CD SC (Sony) or Toshiba. Driver: Apple CD-ROM driver. Note: The Toshiba drive requires a separate driver, which may be obtained from Toshiba. Sun Micro Drive: SUN Microsystems (Sony). Driver: SUN CD-ROM Driver. Note: There is a patch to support structured files. >the following error, when >trying to do a "ls" on its directory contents: > 'hsfs: filetype(0X8) not supported'. > The files that cause the error message are structured files. They are organized in records (fix or variable length). Applications need to retrieve additional file attributes (fix or variable length, and maximum record length) from these files in order to access the contents correctly. Unfortunately, UNIX can only handle stream files (unstructured byte stream). There is currently no application interface to access the extended file attributes and data records in a record format file. (Note: Philips is coming up with an X/Open specification (XCDR) to provide an API to access the ISO 9660 CD-ROM format Disc. It is too early to tell whether it will be approved or not). The design decision when implementing the CD-ROM file system was to ignore all record format files stored in a CD-ROM. This is obviously a mistake. The best way is at least to allow users to access these files. The following is a patch for SunOS 4.1 Sun4c (SPARCSTATION) to correct the above problem: acuraintegra# adb -w vmunix >>>> hs_parsedir+9c?X _hs_parsedir+0x9c: ba0da0ee >>>> hs_parsedir+9c?Wba0da0e6 _hs_parsedir+0x9c: 0xba0da0ee = 0xba0da0e6 >>>> hs_parsedir+14c?X _hs_parsedir+0x14c: ba0da0ee >>>> hs_parsedir+14c?Wba0da0e6 _hs_parsedir+0x14c: 0xba0da0ee = 0xba0da0e6 >>>> $q Note: you can also patch hsfs_node.o with the above patch. The patch for SunOS 4.0.3c (SPARCSTATION) is similar: hs_parsedir+9c?X _hs_parsedir+0x9c: ba0de0ee hs_parsedir+9c?Wba0de0e6 _hs_parsedir+0x9c: 0xba0de0ee = 0xba0de0e6 hs_parsedir+14c?X _hs_parsedir+0x14c: ba0de0ee hs_parsedir+14c?Wba0de0e6 _hs_parsedir+0x14c: 0xba0de0ee = 0xba0de0e6 $q The following are the patch for the sun3: adb -w hsfs_node.o hs_parsedir+56?X _hs_parsedir+0x56: ee6612 hs_parsedir+56?We66612 _hs_parsedir+0x56: 0xee6612 = 0xe66612 hs_parsedir+e4?X _hs_parsedir+0xe4: ee6612 hs_parsedir+e4?We66612 _hs_parsedir+0xe4: 0xee6612 = 0xe66612 $q 6. Who to Contact for Information For questions about how to read the CD-ROM: Jason J. Hyon MS 525-3610 Jet Propulsion Laboratory 4800 Oak Grove Drive Pasadena, CA 91109 818-306-6054 Electronic mail addresses: SPAN: JPLPDS::JHYON Internet: JHYON@jplpds.jpl.nasa.gov NASAmail: jhyon For questions concerning the Mariner 10 Archive EDR product or the Science Digital Data Preservation Task: Amy Hochstettler Culver MS 168-514 Jet Propulsion Laboratory 4800 Oak Grove Drive Pasadena, CA 91109 818-354-4432 Electronic mail addresses: SPAN: MIPL3::ADH875 Internet: ADH875@ipl.jpl.nasa.gov For questions concerning the Mariner 10 Imaging EDR data contact the Planetary Data System's Imaging Node: Leslie Pieri MS 168-522 Jet Propulsion Laboratory 4800 Oak Grove Drive Pasadena, CA 91109 818-354-8320 Electronic mail addresses: SPAN: MIPL3::LJP051 Internet: LJP051@ipl.jpl.nasa.gov OR Eric Eliason United States Geological Survey Branch of Astrogeology 2255 North Gemini Flagstaff, AZ 86001 Electronic mail addresses: SPAN: ASTROG::EELIASON Internet: EELIASON@astrog.span.nasa.gov