PDS_VERSION_ID = PDS3 LABEL_REVISION_NOTE = "2018-10-16 GEO:SHS Added pointer to README.TXT for the PDS4 archive" RECORD_TYPE = STREAM OBJECT = TEXT PUBLICATION_DATE = 2017-05-12 NOTE = "AAREADME.TXT describes this volume." END_OBJECT = TEXT END PLEASE NOTE: This archive has been migrated from PDS3 to PDS4. The contents and directory structure of the PDS3 archive have not changed, but PDS4 metadata in the form of XML files have been added. The file README.TXT in the root directory has more information. The file you are now reading, AAREADME.TXT, was written for the original PDS3 archive and does not have information about the PDS4 additions. ---- Original contents of AAREADME.TXT are below this line. ---- MESSENGER X-Ray Spectrometer Reduced Data Archive Prepared for the Geosciences Discipline Node of the Planetary Data System. ============================================================================== Introduction ============================================================================== This volume contains reduced (RDR) data and associated documentation from the MESSENGER X-Ray Spectrometer (XRS). A complete description of the design of this volume is given in the XRS CDR-RDR software interface specification. An electronic copy of this document is located on this volume in the DOCUMENT directory. This volume is intended for the use of scientists and students in the study of the geography and geochemistry of the planet Mercury. The data may be used for research and publication. ============================================================================== Volume Format ============================================================================== All science data are located under the DATA directory. The INDEX directory contains a listing of all of the data products included on this volume. The CATALOG directory contains PDS documentation describing the mission, spacecraft, instrument, and data set. These include: CATINFO.TXT Description of the CATALOG directory contents. RDR_MAP_DS.CAT RDR Map data set description. RDR_FOOTPRINT_DS.CAT RDR Footprint data set description. DSMAP.CAT Description of the map projection used. INSTRUMENT_HOST.CAT MESSENGER spacecraft description. INSTRUMENT.CAT XRS instrument description. MISSION.CAT MESSENGER mission description. PERSON.CAT MESSENGER mission personnel contact information including XRS personnel, identified as such. REF.CAT MESSENGER mission reference information, including XRS references. Additional information on volume organization is given in the CDR-RDR SIS (described above), and in section the 'Volume Contents' below. ============================================================================== File Formats ============================================================================== The map data products on this volume are provided in JPEG-2000 binary format with extension .JP2; these files conform to ISO/IEC 15444, "JPEG 2000 Image Coding System". The footprint data products on this volume are provided in comma-separated value ASCII format with extension .CSV. Each data file is also accompanied by a detached PDS label file with extension .LBL, an ASCII file containing information describing the data file and data record format. Catalog files (extension .CAT) are provided in ASCII format. Document files describing the volume and the data are given in HTML and PDF formats. Text files and detached label files contain ASCII records terminated with a carriage-return character (ASCII 13) and a line-feed character (ASCII 10). This format allows the files to be read by Mac OS X, MS Windows, UNIX and Linux operating systems. Note that while both label and catalog files are ASCII, some operating systems will not recognize the .LBL and .CAT extensions as ASCII types. It may be necessary to either remap these extensions as ASCII in the system or text browser, or else to open the files from within the text browser. ============================================================================== Volume Contents ============================================================================== Directory Structure and Contents for XRS RDR Data Archive Volume The following illustration shows the directory structure overview for the XRS RDR archive volume, which bears the PDS-assigned volume id MESSXRS_3001. This volume contains the XRS RDR data products, supporting documentation, and any additional files required for the volume to be compliant with PDS standards. The content of the volume is expected to be updated with periodic releases according to the schedule found in the MESSENGER Data Management and Science Analysis Plan (DMSAP). Revised RDRs (if needed) will also be delivered according to the same schedule. Revised RDRs will have an incremented version number in the PDS label. Directory Structure Overview: _________________|___________________ | | | | | ______|______ | | Directory Contents: Directory This is the top-level directory of the data volume. The following are files contained in the root dirctory. AAREADME.TXT: (This file) General information file. Provides users with information about the MESSENGER XRS RDR data products. Directs user to other documents on the volume containing more detailed information. ERRATA.TXT: Text file for identifying and describing errors and/or anomalies found in the current volume, and possibly previous volumes of a set. Any known errors for the associated volume will be documented in this file. This includes revised RDRs meant to replace RDRs in a previous PDS delivery. VOLDESC.CAT: PDS file containing the VOLUME object. This gives a high-level description of the contents of the volume. Information includes: production date, producer name and institution, volume ID, etc. Directory This directory contains files that describe how the reduced data records were derived from the calibrated data records. CALINFO.TXT: Description of CALIB directory files. Directory This subdirectory contains the catalog object files for the entire volume. The following files are included in the catalog subdirectory. CATINFO.TXT: Identifies and describes the function of each file in the catalog directory. RDR_MAP_DS.CAT: Describes the general content of the RDR Map data set. RDR_FOOTPRINT_DS.CAT: Describes the general content of the RDR Footprint data set. DSMAP.CAT: Describes the map projection used to create the elemental ratio maps that form the basis of the RDR Map data set. INSTRUMENT.CAT: Describes physical attributes of the XRS instrument and provides relevant references to published literature. INSTRUMENT_HOST.CAT: Describes the MESSENGER spacecraft. MISSION.CAT: Describes the scientific goals and objectives of the MESSENGER program. It also identifies key people and institutions. PERSON.CAT: Lists and provides contact information for the people involved in the MESSENGER mission, including those involved with XRS. REF.CAT: Provides references (reference objects) to scientific papers and other publications of interest to those using the data, both for XRS and the mission as a whole. Data Directory This is the top level of the directories containing RDRs. Data Directory Subdirectory of the directory which contains the RDR maps. Data Directory Subdirectory of the directory which contains the RDR footprints. Directory This subdirectory contains the documentation that is needed in order to understand and analyze the RDR data products. Files are stored in PDF and HTML format. DOCINFO.TXT: Identifies and describes the function of each file in the DOCUMENT directory. JP2INFO.TXT: Describes the JPEG2000 format in which the map images are stored. Subdirectory XRS_CDR_RDR_SIS.LBL: Detached PDS label for XRS_CDR_RDR_SIS.PDF and XRS_CDR_RDR_SIS.HTM. XRS_CDR_RDR_SIS.PDF: The XRS CDR-RDR SIS: 'MESSENGER Software Interface Specification For The X-Ray Spectrometer Calibrated and Reduced Data Records' in Adobe Acrobat format. XRS_CDR_RDR_SIS.HTM: The XRS CDR-RDR SIS: 'MESSENGER Software Interface Specification For The X-Ray Spectrometer Calibrated and Reduced Data Records' in HTML format. Subdirectory Contains the *.JPG and *.GIF image files called by XRS_CDR_RDR_SIS.HTM. Subdirectory XRS_EDR2CDR2RDR.LBL: Detached PDS label for XRS_EDR2CDR2RDR.PDF and XRS_EDR2CDR2RDR.HTM. XRS_EDR2CDR2RDR.PDF: Description of how the calibrated data records were derived from the experimental data records and how the reduced data records were derived from the calibrated data records in Adobe Acrobat format. XRS_EDR2CDR2RDR.HTM: Description of how the calibration data records were derived from the experimental data records and how the reduced data records were derived from the calibrated data records in HTML format. Directory This subdirectory contains the indices for the XRS RDR data products. The following files are contained in the index subdirectory. INDEX.LBL: Detached PDS label for INDEX.TAB. INDEX.TAB: The RDR index file is organized as a table: there is one entry for each of the data files included in the XRS RDR data sets; the columns contain parameters that describe the observation as well as instrument and spacecraft parameters. INDXINFO.TXT: Identifies and describes the function of each file in the index subdirectory. This includes a description of the structure and contents of each index table in the subdirectory AND usage notes. MD5.LBL: Detached PDS label for MD5.TAB. MD5.TAB: Provides the MD5 checksum (message digest) for each file in the archive, with the exception of the MD5.TAB file itself. ============================================================================== Related PDS Products ============================================================================== The XRS EDR volume (MESSXRS_1001) from which the CDRs were generated is available on the PDS website (http://pds.jpl.nasa.gov), as are the CDRs (MESSXRS_2001) from which the RDRs were derived. ============================================================================== Errata ============================================================================== Every effort has been made to ensure that the data and documentation are of the best possible quality. However, all users are encouraged to verify the correctness of the data prior to submitting any publications or other work based on these data. The file ERRATA.TXT at the root level of this volume contains a list of known deficiencies or caveats associated with data on this volume at the time it was published, if any. It also lists any revisions that have been made to the data set as a whole or to individual products. If you find an error on this volume, please report the error to the PDS Geosciences Node at geosci@wunder.wustl.edu. ============================================================================== Contacts ============================================================================== For questions concerning these data products and documentation, contact: PDS Geosciences Node Washington University Dept. of Earth and Planetary Sciences 1 Brookings Drive St. Louis, MO 63130 314-935-5493 WWW Site: http://pds-geosciences.wustl.edu Electronic mail address: geosci@wunder.wustl.edu For questions regarding PDS Standards or other archive volumes available from the PDS, please contact PDS Operator at the PDS Central Node (at JPL): Internet pds_operator@jpl.nasa.gov Telephone (818) 354-4321 U.S. Mail Planetary Data System, PDS Operator Jet Propulsion Laboratory Mail Stop 202-101 4800 Oak Grove Dr. Pasadena, CA 91109-8099