PDS_VERSION_ID = PDS3 RECORD_TYPE = STREAM OBJECT = TEXT PUBLICATION_DATE = 2013-06-02 NOTE = "This file provides an overview of the Mars Express OMEGA Mars Global Maps Data Set." END_OBJECT = TEXT END The Mars Express OMEGA Mars Global Maps Data Set Introduction ======================================================================== This data set contains high-level map products derived from observational data acquired by the Observatoire pour la Mineralogie, l'Eau, les Glaces et l'Activite (OMEGA) imaging spectrometer on board the Mars Express (MEX) spacecraft. It is intended that this data set will continue to evolve to contain more maps in future releases. The first release of this data set contains 8 global maps of the surface albedo and minerals on Mars. Together they constitutes a unique atlas that will enable users to study the surface of Mars in a global context, providing an unparallelled view into its history and identifying regions of strong interest for future exploration. All maps provided within this data set are results from published scientific work. The maps included are: NIR Albedo Map -------------------------------------- This is a NIR 1.08 micrometer albedo map. Consistent with previous space and ground-based observations it shows that the bright regions are localized in the northern hemisphere over the regions of Tharsis, Arabia Terra and Elysium. In the southern highlands, the regions with the highest albedo are found over the Hellas basin and the region of Promethei. Publication reference [ODY_JGR2012] Ferric Oxide Map -------------------------------------- The identification of ferric oxide (Fe3+), the mineral phase of iron, is made by means of the 0.53 micrometer absorption band. Ferric oxides are both present within the bulk crust and lava outflows, and within the dust oxidized by alteration at the surface. Publication reference [ODY_JGR2012] Dust Map -------------------------------------- This map indicates the presence of ferric oxides in the form of nanoparticles (a few tens of nm in size), responsible for the red colour of Mars. They are interpreted to be the result of a surface highly oxidizing alteration, dominated by an atmospheric interaction, without liquid water playing a role. Publication reference [ODY_JGR2012] Hydrated Mineral Map -------------------------------------- This map shows individual sites where hydrated minerals, formed only in the presence of water, were detected by MEX/OMEGA and MRO/CRISM instrument. More than ten different hydrous minerals have been found on Mars, with many occurrences found in the same site. The distribution of hydrated minerals shows that aqueous alteration began very early in Mars' history, more than 4Gyrs ago. Their presence shows that in its ancient history Mars has harbored at least transient habitable conditions, and this map indicates sites with well preserved records of them. Publication reference [CARTER_JGR2013] Olivine Maps (3 maps) -------------------------------------- Olivine and pyroxene tell the story of volcanism, with differences in the chemical composition of the solidified lavas representing the evolution of the temperature and pressure inside the planet. Some of the most pristine olivines are found around impact craters that have excavated very ancient samples of the mantle from below the crust. Olivine has a broad, complex absorption centered near 1 micrometer that varies in width, position, and shape with grain size and Fo number. Three different spectral parameters are used to detect olivine with: - rich Mg content and/or small grain size and/or low abundance, - high iron content and/or large grain size and/or high abundance, - large Fe content and/or with large grain size and/or with high abundance. Publication reference [ODY_JGR2012] Pyroxene Map -------------------------------------- The identification of pyroxene is made by means of the 2 micrometer absorption band. Like olivine, pyroxene results from volcanic processes that trace the evolution of the planet's interior, its chemical composition acting as a tracer of the evolution of the temperature and pressure inside the planet. The widespread pyroxene-bearing terrains result from magmatic and volcanic processes, translating the evolution of Mars upper mantle and crust. Publication reference [ODY_JGR2012] Data Formats ======================================================================== The OMEGA Mars Global Maps data products are primarily available in PDS format in the DATA directory of this data set. Raster maps are formatted using the PDS IMAGE object, and vector maps are formatted using the PDS SPREADSHEET object. Data products are also available in Geographic Information System (GIS) format in the EXTRAS directory of this data set. Raster maps are provided in ISIS and GeoTiff format, and vector maps are provided in ESRI Shapefile and KML format. Applicable Software ======================================================================== PDS data products can be read using the PDS SBN IDL Reader available here: http://pds-smallbodies.astro.umd.edu/tools/tools_readPDS.shtml In addition, the CSV format can be loaded into Microsoft Excel or any other spreadsheet software. GIS data products can be read using GIS software such as: ISIS, ArcGIS, or Quantum GIS. Additionally the overall data set maps can be quickly visualised using the Google Earth interface through the KML file located at the root of the EXTRAS directory. Google Earth is freely downloadable from: http://www.google.com/earth/download/ge Data Set Contents ======================================================================== Files within this data set are organized into a series of subdirectories below the top-level directory. Top-level Directory -------------------------------------- AAREADME.TXT The file you are currently reading ERRATA.TXT This file lists known errors and anomalies for this data set. It is occasionally updated if additional notes about the data set are needed. VOLDESC.CAT This text file contains a description of the volume contents as a PDS catalog object. It is a required file for PDS data sets. BROWSE Directory -------------------------------------- The BROWSE directory contains the OMEGA Global Maps images in reduced size and converted to PNG for quickly visualising the corresponding data products available in the DATA directory. It follows the same directory structure and files naming scheme as the DATA directory. Note that map color legend corresponding to the each browse image is available in the EXTRAS directory. CATALOG Directory -------------------------------------- Files in the CATALOG directory are text files containing documentation formatted in PDS object description language. The files contain information about the MEX mission and spacecraft, the OMEGA instrument, this data set, cited references, and used map projections. DATA Directory -------------------------------------- Data files in PDS format are organised in the DATA directory using the following directory structure and naming scheme: |___ ALBEDO | |___ ALBEDO_R1080_EQU_MAP.IMG NIR Albedo Map | |___ ALBEDO_R1080_EQU_MAP.LBL | |___ FERRIC | |___ FERRIC_BD530_EQU_MAP.IMG Ferric Oxide Map | |___ FERRIC_BD530_EQU_MAP.LBL | |___ FERRIC_NNPHS_EQU_MAP.IMG Dust Map | |___ FERRIC_NNPHS_EQU_MAP.LBL | |___ HYDROUS | |___ HYDROUS_SITES_GEO_MAP.CSV Hydrated Mineral Map | |___ HYDROUS_SITES_GEO_MAP.LBL | |___ OLIVINE | |___ OLIVINE_OSP1_EQU_MAP.IMG Olivine OSP1 Map | |___ OLIVINE_OSP1_EQU_MAP.LBL | |___ OLIVINE_OSP2_EQU_MAP.IMG Olivine OSP2 Map | |___ OLIVINE_OSP2_EQU_MAP.LBL | |___ OLIVINE_OSP3_EQU_MAP.IMG Olivine OSP3 Map | |___ OLIVINE_OSP3_EQU_MAP.LBL | |___ PYROXENE |___ PYROXENE_BD2000_EQU_MAP.IMG Pyroxene Map |___ PYROXENE_BD2000_EQU_MAP.LBL Each PDS data product consist of an object data file containing the actual data (IMG, CSV) and a corresponding label file (LBL) with descriptive meta-data. DOCUMENT Directory -------------------------------------- The DOCUMENT directory contains the OMEGA Experiment to Archive Interface Control Document (EAICD). It also contains the scientific papers in PDF format corresponding to the map products archived in this data set. EXTRAS Directory -------------------------------------- The EXTRAS directory contains all data products available in the DATA directory in GIS format. It also contains a KML file allowing to visually browse the content of the data set. It follows the same directory structure and files naming scheme as the DATA directory. See the file EXTRINFO.TXT file for details. INDEX Directory -------------------------------------- The INDEX directory contains PDS index files for this data set. An index file is an ASCII table with each record (or line) in the table containing information about a single product in the DATA or in the BROWSE directory. Whom To Contact For Information ======================================================================== The maps archived in this data set were produced and provided by Jean-Pierre Bibring, OMEGA Principal Investigator, and his team members: Francois Poulet, francois.poulet@ias.u-psud.fr Institut d'Astrophysique Spatiale Anouck Ody, aody@ias.u-psud.fr Institut d'Astrophysique Spatiale John Carter, john.carter@ias.u-psud.fr Institut d'Astrophysique Spatiale This data set was designed and produced by Nicolas Manaud, European Space Astronomy Centre, Madrid, Spain. Nicolas Manaud, nmanaud@sciops.esa.int ESA/ESAC, Mars Express Data Handling and Archiving Scientist Dave Heather, dheather@rssd.esa.int ESA/ESAC, ESA's Planetary Science Archive Coordinator Olivier Witasse, owitasse@rssd.esa.int ESA/ESTEC, Mars Express Project Scientist