PDS_VERSION_ID = PDS3 RECORD_TYPE = FIXED_LENGTH RECORD_BYTES = 80 OBJECT = TEXT INTERCHANGE_FORMAT = ASCII PUBLICATION_DATE = 1997-11-07 NOTE = "N/A" END_OBJECT = TEXT END Mars Global Surveyor Radio Science Team Raw Data Archive Cruise Phase (MGS-M-RSS-1-CRU-V1.0) AAREADME.TXT 07 November 1997 R.A. Simpson Stanford University ============================================================================== INTRODUCTION ============================================================================== This compact disc contains archival raw, partially processed, and ancillary/supporting radio science data acquired during Mars Global Surveyor (MGS) Cruise to Mars. The radio observations were carried out using the MGS spacecraft and Earth-based receiving stations of the NASA Deep Space Network (DSN). The observations were designed to test the spacecraft radio system, the DSN ground system, and MGS operations procedures. Also, during a three- week period in late April and early May 1997 data were collected in a search for gravitational waves. Each disc in the volume set contains data from part of the Cruise period. Launch occurred on 6 November 1996; the Cruise Phase ended on 2 September 1997. Data are organized in approximate chronological order, though receipt at Stanford was generally more important in determining placement than strict order of generation or applicability. For example, data from early Cruise were collected less frequently and tend to be organized more by data type than by time. Beginning with the Gravitational Wave Experiment (GWE) in mid-April 1997, the chronological ordering became better. A table of contents is included with each volume, listing each file in the volume; a separate table of contents shows all files within the data set. The table below lists the individual volumes (CDs) created to date and (very briefly) their respective contents. VOLUME_ID Start Date End Date Notes --------- ------------------- ------------------- ------------------------- MORS_0101 1996-11-07 (96/312) 1996-11-10 (96/315) Launch (96/311) MORS_0102 1996-11-11 (96/316) 1996-11-13 (96/318) MORS_0103 1996-11-14 (96/319) 1996-11-16 (96/321) MORS_0104 1996-11-17 (96/322) 1996-11-19 (96/324) MORS_0105 1996-11-20 (96/325) 1996-11-22 (96/327) MORS_0106 1996-11-23 (96/328) 1996-11-27 (96/332) MORS_0107 1996-11-28 (96/333) 1996-11-30 (96/335) MORS_0108 1996-12-01 (96/336) 1996-12-04 (96/339) MORS_0109 1996-12-05 (96/340) 1996-12-09 (96/344) MORS_0110 1996-12-10 (96/345) 1996-12-14 (96/349) MORS_0111 1996-12-15 (96/350) 1997-01-02 (97/002) MORS_0112 1997-01-03 (97/003) 1997-01-08 (97/008) MORS_0113 1997-01-09 (97/009) 1997-01-15 (97/015) MORS_0114 1997-01-16 (97/016) 1997-01-21 (97/021) Switch to HGA (97/016) MORS_0115 1997-01-22 (97/022) 1997-01-24 (97/024) MORS_0116 1997-01-25 (97/025) 1997-01-27 (97/027) MORS_0117 1997-01-28 (97/028) 1997-01-31 (97/031) MORS_0118 1997-02-01 (97/032) 1997-02-14 (97/045) MORS_0119 1997-02-15 (97/046) 1997-02-17 (97/048) ============================================================================== VOLUME SET INFORMATION ============================================================================== This disc is one of several which contain raw data from the MGS Cruise Phase. Each archive volume has the structure illustrated in the diagram below. Not all directories or file types will be present on every disc; for example, only some volumes contain Archival Tracking Data Files (TDF directory). In cases where the directory contains no files, the directory itself has been omitted from the CD-WO volume. The primary data types for these volumes are the DSN Original Data Record (ODR), the Orbit Data File (ODF), and the Archival Tracking Data File (ATDF or TDF). ODR files are stored in the ODR directory; ODFs are stored in the ODF directory. The ATDF is considered backup data to both the ODR and ODF; those files are stored in the TDF directory. Each ODR, ODF, or TDF appears only once in the volume set though (in a few cases) two versions of the same file (with different file names) may appear. The primary data files are accompanied by a number of ancillary files in the CALIB directory; these include leap second files, planetary constant files, spacecraft clock conversion files, decommutation maps, and others. Documentation is in the DOCUMENT directory. CALIB and DOCUMENT files appear on every volume where they could be useful. There are also about two dozen ancillary file types that are organized into directories of their own. These include angular momentum desaturation files (AMD directory), spacecraft engineering data in packet form (EPK directory), spacecraft engineering data in channelized form (ECH directory), light-time files (LIT directory), ephemerides (SPK directory), and others. Each of these files appears only once in the volume set; users should consult the tables of contents in the INDEX directory for file locations. The diagram below shows the organization of each volume, starting from the root of the compact disc. root | |- AAREADME.TXT |- ERRATA.TXT |- VOLDESC.CAT | |- CALIB | | | |- CALINFO.TXT Overview of directory | |- yaaabbbC.SCK Clock conversion file | |- ydddeeeF.TLS Leap second file | |- ... | |- *.LBL Detached PDS labels | |- CATALOG | | | |- CATINFO.TXT Streamlined PDS catalog files | |- MISSION.CAT for mission, host, instrument, | |- INSTHOST.CAT references, personnel, and | |- INST.CAT data set (files evolve as | |- REF.CAT mission progresses). | |- PERSON.CAT | |- DATASET.CAT | |- DOCUMENT | | | |- DOCINFO.TXT Overview of directory | |- MGSRSSIS.TXT SIS document for this data set | |- RSC11_11.TXT ODR SIS document | |- TK_FTP.TXT Ephemeris documentation | |- TK_DESCR.TXT | |- TK_INSTL.TXT | |- TRK_2_25.TXT TDF SIS document | |- ... | |- INDEX | | | |- INDXINFO.TXT Overview of directory | |- INDEX.LBL Label to INDEX.TAB | |- INDEX.TAB List of data file contents, this volume | |- CUMINDEX.LBL Label to CUMINDEX.TAB | |- CUMINDEX.TAB List of data file contents, all volumes | |- AGK |- AMD |- DKF |- ECH |- ECS |- EOP |- EPK |- FBR |- HEA Data |- HGA Directories |- ION |- LIT |- MCH |- MIF |- MPD |- MPK |- ODF |- ODR |- ONF |- OPT |- SFO |- SOE |- SPK |- TCK |- TDF |- TIM |- TRO `- WEA ============================================================================== ERRATA ============================================================================== A cumulative list of errors and changes is maintained in the file ERRATA.TXT at the root level of each volume. ERRATA.TXT in higher numbered volumes (or higher version numbers) will have errors for earlier volumes. ============================================================================== DISC FORMAT ============================================================================== The disc is organized according to the PDS standard for "one data set, many volumes." This file (AAREADME.TXT), a PDS volume object definition (VOLDESC.CAT), and the listing of errors and changes (ERRATA.TXT) are included at the root level. The following directories of descriptive material are also at the root level: CALIB contains files of constants, clock conversions, decommutation maps, and other material useful in working with the data. CATALOG contains descriptive files for cataloging the data on this disc. DOCUMENT contains a plain text Software Interface Specification (SIS) for data types (if available), directions on how to obtain NAIF SPICE software, and other documentation. INDEX contains index information on each of the data files included in this disc; it also includes a cumulative index to all files in this volume set. The remaining directories at the root level contain data files and detached PDS labels. ============================================================================== FILE FORMAT ============================================================================== All data files on the disc are accompanied by detached PDS labels, which describe their contents. PDS TEXT objects have attached labels. Detached labels have the same file name as the data file except that the label name has the suffix "LBL". Detached PDS labels for multi-file documents have distinctive file names ending with ".LBL". Detailed documentation on file structure is available for some file types in Software Interface Specifications in the DOCUMENT directory. ODF, ODR, and TDF files have full PDS labels which describe format and content completely. For other file types, where no electronic version of the SIS was available, the PDS label provides a reference to a hard copy document. See the DESCRIPTION keyword in each PDS label. Text files, including data files of ASCII text and all labels (*.LBL files) and tables (*.TAB files), are delimited with carriage-return (ASCII 13) line-feed (ASCII 10) pairs at the end of each line. Detached labels and text files (*.TXT file names) have fixed length records of 80 bytes to facilitate their use as either fixed-length record files or as stream files with carriage-return line-feed delimiters. Catalog files (*.CAT files) have fixed length records of 72 bytes ending with a carriage-return line-feed pair. The VOLDESC.CAT file in the root is an exception; it has 80 byte fixed-length records. ============================================================================== SOFTWARE ============================================================================== Software for parsing 8- and 12-bit samples from ODR data records has been developed at several institutions to support NASA flight projects. Because parsing must be done at the bit level and the code is usually written for a narrow platform-specific application, no software has been included as part of this archival product. ============================================================================== ACKNOWLEDGMENTS ============================================================================== These data were collected under auspices of the Mars Global Surveyor Project. G. Leonard Tyler of Stanford University was the Radio Science Team Leader. Members of the Team and its support elements involved in data acquisition and validation included Patricia Priest, John Armstrong, William Sjogren, Frank Lemoine, and Joe Twicken. At PDS the assistance of Betty Sword was appreciated. ============================================================================== DISCLAIMER ============================================================================== Although considerable care has gone into making this volume set, errors are both possible and likely. Users of the data are advised to exercise the same caution as they would when dealing with any other unknown data set. Reports of errors or difficulties would be appreciated. Please contact one of the persons listed below. ============================================================================== COGNIZANT PERSONNEL ============================================================================== The person most directly responsible for construction and release of this volume set is Dick Simpson, Experiment Engineer for the Mars Global Surveyor Radio Science Team and Radio Science Advisor to the Planetary Data System. Although many people contributed to the volume set, any faults in the product are his alone. Richard A. Simpson Center for Radar Astronomy Durand Bldg - Room 232 Stanford University Stanford, CA 94305-9515 Tel: 650-723-3525 FAX: 650-723-9251 rsimpson@magellan.stanford.edu G. Leonard Tyler Center for Radar Astronomy Durand Bldg - Room 232 Stanford University Stanford, CA 94305-9515 Tel: 650-723-3535 FAX: 650-723-9251 len@nova.stanford.edu