Radio Science Subsystem (RSS) Raw Data Magellan Mission to Venus This PDS4 bundle has been migrated from the PDS3 data volumes mg_2201 through mg_2214. Each document and data product in this bundle is described by a PDS4 label in a separate file with the same name but with the extension XML. PDS4 labels are XML (eXtended Markup Language) files that conform to the PDS4 Information Model XML schema at https://pds.nasa.gov/pds4/schema/released/. They are best viewed in an XML-aware text editor, and may be used by software that can manipulate XML documents. The Magellan RSS raw product bundle consists of radio science measurements made using the Magellan spacecraft and Earth-based stations of the NASA Deep Space Network (DSN). The bundle includes seven collections: Code Product Type Description Storage Format data_browse BROWSE Quick look browse products PNG calib Calibration Doppler predict and uplink frequency files CSV data_attitude Spacecraft Attitude Quaternions and HGA pointing CSV data_odr ODR Original Data Record RSC-11-11 Open Loop data Binary data_tdf TDF Archival Tracking Data File TRK-2-25 Binary document Document Documentation files ASCII spice_kernels SPICE SPICE Kernels ASCII This bundle was created by the Radio Science Sub-Node of the Ring Moon Systems Node of the Planetary Data System. It was archived by the Atmospheres Node Node of the Planetary Data System. Questions about this bundle may be directed to rssn@jpl.nasa.gov. Contents of the original PDS3 AAREADME.txt follow below: ---------------------------------------------------------------------------- PDS_VERSION_ID = PDS3 RECORD_TYPE = FIXED_LENGTH RECORD_BYTES = 80 OBJECT = TEXT INTERCHANGE_FORMAT = ASCII PUBLICATION_DATE = 1996-09-16 NOTE = "N/A" END_OBJECT = TEXT END Magellan Radio Occultation Raw Data Archive (MGN-V-RSS-1-ROCC-V2.0) AAREADME.TXT 16 September 1996 R.A. Simpson Stanford University ============================================================================== INTRODUCTION ============================================================================== This compact disc contains archival raw and partially processed data acquired during radio occultation observations of Venus. The experiments were carried out using the Magellan spacecraft and Earth-based transmitting and receiving stations of the NASA Deep Space Network. Each disc in the volume set contains data from a limited number of radio occultation observations. The disc identifiers and the coverage are given in the table below. Where no specific time is shown, the entire day is included. VOLUME_ID Start Date/Time End Date/Time --------- ------------------------- ------------------------- MG_2201 05 October 1991 21 February 1992 MG_2202 07 March 1992 11 March 1992 MG_2203 07 December 1992 03:21:45 07 December 1992 06:52:08 MG_2204 07 December 1992 06:52:09 24 June 1994 21:34:39 MG_2205 24 June 1994 22:20:01 30 July 1994 13:57:08 MG_2206 30 July 1994 13:57:09 30 July 1994 18:36:12 MG_2207 30 July 1994 18:36:13 01 October 1994 13:20:13 MG_2208 01 October 1994 13:23:47 01 October 1994 16:58:56 MG_2209 01 October 1994 16:58:57 02 October 1994 MG_2210 06 October 1994 08 October 1994 21:46:59 MG_2211 08 October 1994 21:47:00 10 October 1994 16:57:10 MG_2212 10 October 1994 16:57:11 11 October 1994 14:26:55 MG_2213 11 October 1994 14:26:56 11 October 1994 22:26:40 MG_2214 11 October 1994 22:26:41 12 October 1994 10:07:26 ============================================================================== VOLUME SET INFORMATION ============================================================================== This disc is one of fourteen which contain raw radio occultation data from the Magellan Mission at Venus. Each archive volume has the structure illustrated in the diagram below. Not all directories or file types will be populated on every disc; for example, only the first volume will have TUN files. In cases where the directory contains no files, the directory itself has been omitted from the CD-WO volume. The primary data type for these volumes is the DSN Original Data Record (ODR). ODR files are stored in the ODR directory; they are organized chronologically within the volume set with the earliest ODRs appearing on the first CD-WO volume. Archival Tracking Data Files (ATDFs or TDFs) are considered backup data to the ODR; they also appear chronologically on the volume set, synchronized with ODRs. Each ODR and TDF file appears only once in the volume set. Each ODR is accompanied by a number of ancillary files in the CALIB and GEOMETRY directories. Documentation is in the DOCUMENT directory. Ancillary and document files appear on every volume where they could be useful in analyzing the corresponding ODRs. TDFs also serve in an ancillary role; as noted above and because of their volume, TDFs are not repeated, however. The BROWSE directory appears only on the last volume. It contains PostScript plot files which summarize the contents of each ODR file. Each file is a set of three 'landscape' plots arranged for printing on a single 8-1/2 x 11 inch page. Each page includes a histogram of data samples, a plot of 60-second averaged power spectra, and a plot of 1-second averages of sample power versus time for each receiver channel recorded. These plots were not originally planned for inclusion in the archival data set; a few were incorrectly set up and/or calculated, and those erroneous PostScript files have not been updated. For example, the volume of data was incorrectly estimated in 42741734.ODR and the power vs time plot was not completed; instead, a second copy of the power spectra appears in the lower left panel in BROWSE files 42741734.PS1 and 42741734.PS2. Even in this case, the histograms and power spectra should allow browsers to inspect the data at low resolution before selecting which ODR files to study in detail. PostScript files were created using MATLAB 4.1 routines running under SunOS 4.1.3 on a SPARC-2 UNIX workstation. Individual plot files were combined using the utility 'psmulti', a PERL script written by D. Murray Laing. Filenames within the BROWSE directory have the form ydddhhmm.PSc where y is the least significant digit of the data acquisition year, ddd is the 3-digit day-of-year, hh is the 2-digit hour, and mm is the 2-digit minute. The suffix character 'c' denotes the receiver channel in the corresponding ydddhhmm.ODR raw sample file from which the plot data were derived; 'c' is a digit in the range 1-4. root | |- AAREADME.TXT |- ERRATA.TXT |- VOLDESC.CAT | |- CALIB | | | |- CALINFO.TXT Overview of directory | |- DSSnnnnn.TAB S-band Doppler predicts (MG_2201 only) | |- DSXnnnnn.TAB X-band Doppler predicts (MG_2201 only) | |- TUNnnnnn.TAB Uplink tuning file (MG_2201 only) | |- ... ... | |- HGA_DOC.ASC HGA antenna pattern description, | |- ... appendices, and figures (all CDs) | |- *.LBL Detached PDS labels | |- DOP_PRED.FMT Detached format file (MG_2201 only) | |- TUN.FMT Detached format file (MG_2201 only) | |- CATALOG | | | |- CATINFO.TXT Streamlined PDS templates | |- MISSION.CAT for mission, host, | |- INSTHOST.CAT instrument, references, | |- INST.CAT personnel, and data set. | |- REF.CAT | |- PERSON.CAT | |- DATASET.CAT | |- DOCUMENT | | | |- DOCINFO.TXT Overview of directory | |- DAT_IOM.ASC Experiment and data description, | |- ... appendices, and figures | |- FILELIST.TAB Table of file inter-relationships | |- QUA_DOC.TXT Quaternion description for 5 Oct 91 | |- ROCC_SIS.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 | |- *.LBL Detached PDS labels | |- GEOMETRY | | | |- GEOMINFO.TXT Overview of directory | |- MGNnnnnn.TSP SPK file for orbit nnnnn | |- SPK files for other orbits | |- DRFnnnnn.TAB Quaternion and HGA pointing files | |- FILnnnnn.TAB for orbit nnnnn (MG_2201 only) | |- HGAnnnnn.TAB | |- QCFmmmmm.TXT Quaternion coefficients for day mmmmm | |- QUAmmmmm.TAB Quaternion values for day mmmmm | |- ... Files for other orbits | |- *.FMT Detached format files | |- *.LBL Detached PDS labels | |- INDEX | | | |- INDXINFO.TXT | |- INDEX.LBL | |- INDEX.TAB | |- CUMINDEX.LBL | |- CUMINDEX.TAB | |- ODR Data directories |- TDF | |- BROWSE | |- ydddhhmm.PS1 Summary plots in PostScript format |- ydddhhmm.PS2 (included on MG_2214 only) |- ydddhhnn.PS1 |- ... ============================================================================== 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. During peer review of the volume set, a number of errors were identified in both file format and content. For the most part, these could be remedied editorially; but some encapsulated PostScript files in the DOCUMENT directory were regenerated and version 1 (black and white) PostScript versions of EPS files were added in both the DOCUMENT and CALIB directories. Revised files were included in a remastered version of the final volume (MG_2214). Users should refer to ERRATA.TXT on MG_2214 for details and take final versions of these files from MG_2214 wherever possible. ============================================================================== 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 tables of predicted Doppler offsets on received signals and tables from which transmitted signal frequencies can be calculated (MG_2201 only), and reports on measurement of high-gain antenna patterns. CATALOG contains descriptive files for cataloging each of the data types included in this disc. DOCUMENT contains a plain text Software Interface Specification (SIS) for each data type, if available, plus other documentation. GEOMETRY contains NAIF SPK files giving spacecraft and planetary ephemerides during the observation period, and contains one or more types of attitude information for reconstructing spacecraft antenna pointing if the high- gain antenna was not continuously pointed toward Earth. 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. BROWSE contains PostScript files which provide an overview of ODR contents (included only on the last volume, MG_2214). The remaining directories at the root level (ODR and TDF) contain data files and detached PDS labels. ============================================================================== FILE FORMAT ============================================================================== All data files (ODRs and TDFs) on the disc are accompanied by detached PDS labels, which describe their contents. Ancillary files also have PDS labels, most of which are detached. 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 ODR and TDF file types in Software Interface Specifications in the DOCUMENT directory. 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. NB: A 32-byte label record at the beginning of each data tape (see Section D1 in RSC11_11.TXT, DOCUMENT directory) been preserved in the PDS label for each ODR. It is NOT retained in the data file. 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, catalog files, and text files (*.TXT or *.ASC file names) have record lengths of 80 bytes so can be handled either as fixed-length record files or as stream files with carriage-return line-feed delimiters. ============================================================================== 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 ============================================================================== This archiving project was initiated by Steve Lee of the Planetary Data System (PDS) Atmospheres (ATM) Discipline Node (DN) at the University of Colorado. A prototype CD (MG_2201 Version 1) containing the radio occultation files from 5-6 October 1991 was delivered to the ATM DN in early 1995. Version 2 of the archive -- including raw data from all Magellan radio occultations -- was completed with support from the Central Node of PDS (Jet Propulsion Laboratory, Pasadena, CA). The archival products which resulted from this activity have been delivered to PDS. Assistance in developing PDS formats was provided principally by Ron Joyner of PDS at JPL. The overall design was based on an archival data set from Mars Observer Cruise radio science observations. Assistance and review by the investigators for the Magellan radio occultation experiment (Jon Jenkins and Paul Steffes) was also important. ============================================================================== 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 Richard 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. The Team Leader for the Mars Global Surveyor Radio Science Team and Principal Investigator for this archiving activity is G. Leonard Tyler. The investigator most directly involved with analysis of the data was Jon Jenkins. Richard A. Simpson Center for Radar Astronomy Durand Bldg - Room 232 Stanford University Stanford, CA 94305-9515 Tel: 415-723-3525 FAX: 415-723-9251 rsimpson@magellan.stanford.edu G. Leonard Tyler Center for Radar Astronomy Durand Bldg - Room 232 Stanford University Stanford, CA 94305-9515 Tel: 415-723-3535 FAX: 415-723-9251 len@nova.stanford.edu Jon M. Jenkins MS 245-3 NASA Ames Research Center Moffett Field, CA 94035-1000 Tel: 415-604-0208 FAX: N/A jenkins@nova.stanford.edu