PDS_VERSION_ID = PDS3 LABEL_REVISION_NOTE = "2011-08-29, L. Granroth (UIowa) clarifications; 2016-02-29, C. Piker (UIowa) updates;" RECORD_TYPE = STREAM INSTRUMENT_HOST_NAME = "MARS EXPRESS" INSTRUMENT_HOST_ID = "MEX" MISSION_NAME = "MARS EXPRESS" OBJECT = TEXT PUBLICATION_DATE = 2016-07-22 NOTE = "AAREADME.TXT describes the MEX MARSIS AIS data archive for the Planetary Science Archive, PSA, and the Planetary Data System, PDS." END_OBJECT = TEXT END Mars Express Active Ionospheric Sounder (AIS) Volume MEXMDI_1006, Release 5, Revision 0 Covering Orbits 13970 to 15520 * Introduction * Volume Overview - Quick Start Guide * Volume Contents and Structure * Disclaimer * Acknowledgments ============================================================================== Introduction ============================================================================== This release of volume MEXMDI_1006 contains documentation and all available Mars Express Active Ionospheric Sounding (AIS) Science data for the fifth extended mission, from spacecraft event time (SCET) 2015-01-03T15:34:25.000 to 2016-03-30T13:02:56.000. AIS is a component of the Mars Advanced Radar for Subsurface and Ionospheric Sounding (MARSIS) instrument. The scientific objectives of AIS are the mapping and study of the ionosphere around Mars, as well as its solar interactions. Note that in this and other documents in this volume orbit numbers or ranges of orbit numbers are often designated with four lower-case x characters, as in xxxx. Orbit numbers before orbit 10000 actually occupy four characters, but from 10000 onward, it should be noted that five characters are used for orbit numbers in file names, directory names, etc. ============================================================================== Volume Overview - Quick Start Guide ============================================================================== All calibrated binary data contained in the MEX AIS volume is viewable in the Portable Network Graphics (PNG) format. The PNGs reside in the BROWSE/ACTIVE_IONOSPHERIC_SOUNDER subdirectory and are grouped into ten- orbit subdirectories; these are overview plots of the entire orbit. [BROWSE] | |-[ACTIVE_IONOSPHERIC_SOUNDER] | |-[RDRxxxX] | |-FRM_AIS_RDR_xxxx.PNG One directory below the spectrogram plots are ionograms for each ionospheric sounding event, grouped into single orbit directories. [BROWSE] | |-[ACTIVE_IONOSPHERIC_SOUNDER] | |-[RDRxxxX] | |-[RDRxxxx] | |-FRM_AIS_RDR_xxxx_nnn.PNG The overview spectrogram plots are accessable through HTML files located in the EXTRAS directory. The HTML files contain links to the browse products, i.e. one may "browse" the BROWSE products via HTML. [EXTRAS] | |-[BROWSEALL] |-[ACTIVE_IONOSPHERIC_SOUNDER] | | | |-[RDRxxxX] Thumbnails for the ionograms grouped into | | ten-orbit directories. | | | |-BROWSE.HTM HTML file containing the thumbnail | ionograms for the ten orbits. |-[ANCILLARY] Thumbnails HTML page decoration | |-INDEX.HTM Links to the thumbnail plots of the Active Ionospheric Sounder data. The data files from which the browse products are produced are located in the DATA directory and grouped in sets of ten orbits. [DATA] | |-[ACTIVE_IONOSPHERIC_SOUNDER] | |-[RDRxxxX] | |-FRM_AIS_RDR_xxxx.DAT The binary data format is 4-byte aligned, containing MSB (big-endian) integers, ASCII text, and IEEE floating point values. Format details are given in the file LABEL/AIS_FORMAT.FMT and in the label files associated with each individual data file, DATA/ACTIVE_IONOSPHERIC_SOUNDER/ RDRxxxX/FRM_AIS_RDR_xxxx.LBL. Following is a general overview of the data file format. BINARY DATA FORMAT +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ record 1 | TIME | INSTRUMENT_STATUS | FREQUENCY | SPECTRAL_DENSITIES | +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ record 2 | TIME | INSTRUMENT_STATUS | FREQUENCY | SPECTRAL_DENSITIES | +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ record 3 | TIME | INSTRUMENT_STATUS | FREQUENCY | SPECTRAL_DENSITIES | +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ * **** ***************** ********* ****************** record n | TIME | INSTRUMENT_STATUS | FREQUENCY | SPECTRAL_DENSITIES | +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Byte 1 49 77 81 400 TIME - The beginning of the sounding event in the following formats SCLK - spacecraft clock with partition flag UTC_DAY - days since 1958-01-01 00:00 and millisecond of day (the JPL historical epoch) UTC_ASCII - Spacecrafte event time in human readable ISO-8601 format INSTRUMENT_STATUS - Instrument parameters such as gain settings, and transmit power levels. FREQUENCY - The transmit frequency used for the sounding activity. SPECTRAL_DENSITIES - A time series of 80 samples corresponding to the received power. To calculate apparent range to the source of each reflection, constants provided in: [CATALOG] | |-AISDS.CAT are required. Many spectral densities measured by MARSIS are not generated via remote reflection but instead are due to excitations of the local plasma. ============================================================================== Volume Contents and Structure ============================================================================== This volume follows ISO 9660 Level 2 standards with respect to file and directory naming. The volume layout is as follows: [MEX-M-MARSIS-3-RDR-AIS-EXT5-V1.0] (root directory) | |-AAREADME.TXT Plain text describing volume contents, | organization, and its use (this file). | |-ERRATA.TXT Describes known deficiencies or caveats in the | data on this volume. | |-VOLDESC.CAT High level description of volume contents. | |-[BROWSE] Contains browse plots depicting the data. | | | |-[ACTIVE_IONOSPHERIC_SOUNDER] | | | |-[RDRxxxX] Plots of the Active Ionospheric Sounder | | Spectrograms for each orbit | | | |-[RDRxxxx] Plots of each Ionogram in the | orbit xxxx. | |-[CATALOG] Information about the Mars Express mission, spacecraft, | and Active Ionospheric Sounder (AIS) Instrument; lists | the cognizant personnel and references relevant | documentation. | |-[DATA] Binary archived data from the Active Ionospheric | | Sounder instrument. | | | |-[ACTIVE_IONOSPHERIC_SOUNDER] | | | |-[RDRxxxX] Data from the Active Ionospheric Sounder | for each orbit. | |-[DOCUMENT] Instrument papers, Data Management Plans, Electronic | Interface Control Documents, etc. | |-[EXTRAS] Bonus content not necessarily conforming to archiving | standards. Included are HTML files with thumbnails | to navigate the browse products. | |-[INDEX] Volume and cumulative indices of archive products. | |-[LABEL] Format descriptions of the archived data products. ============================================================================== Whom to Contact for Information ============================================================================== MEX Project Scientist Dmitri Titov email: dmitri.titov@esa.int Mars/Venus Express Archive Scientist: Emmanuel Grotheer email: egrotheer@sciops.esa.int For any PSA related issues: PSA Helpdesk: psahelp@rssd.esa.int ============================================================================== * Disclaimer All trademarks are acknowledged as the property of their respective owners. The producers and publishers of this archive do not endorse any commercial entities which may be mentioned for clarity. ============================================================================== * Acknowledgments These data were collected under the auspices of the Mars Express project. Donald A. Gurnett was the Active Ionospheric Sounder Principal Investigator. Over the years, the archiving effort at The University of Iowa was supported by R. Huff, L. Granroth, R. Johnson, C. Piker and D. Morgan. The archiving effort was supported by the Planetary Science Archive and the extraordinary assistance of D. Heather. ==============================================================================