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NASA Space Science Data Coordinated Archive Header



Availability: Archived at NSSDC, accessible from elsewhere


This description was generated automatically using input from the Planetary Data System.

Data Set Overview ================= This data set contains all the unchannelized telemetry from the Microscopy, Electrochemistry, and Conductivity Analyzer (MECA), a payload on the Phoenix 2007 Mars mission, with the exception of the optical microscope images, which can found on the Imaging node. Included here are data from the Wet Chemistry Laboratory (WCL), Thermal and Electrical Conductivity Probe (TECP), Atomic Force Microscope (AFM), and all the ancillary electronic data that describe the configuration of the instrument when the data was acquired. Collectively, the data set is useful for characterizing the icy soils on the northern plains of Mars, at and slightly below the surface. Specifically, data from the WCL is useful in determining the major aqueously solvated components of martian soil; data from the AFM complements the OM data in characterizing dust-size particles that contribute to Aeolian processes; and data from the TECP is useful in understanding the state and transport of water in all phases both under and above the surface. More information is found in HECHTETAL2008, KOUNAVESETAL2008, and ZENTETAL2008. Processing ========== The Committee On Data Management and Computation (CODMAC) data level numbering system is used to describe the processing level of the EDR data product. MECA Non-Imaging EDR data products are considered CODMAC Level 2 or Edited Data (equivalent to NASA level 0) products. The EDR data files are generated from Level 1 or Raw Data, which are the telemetry packets within the project specific Standard Formatted Data Unit (SFDU) record. The philosophy of this Level 2 product archive is to preserve all the data in the most pristine form, edited only to consolidate packets, eliminate gaps, and remove redundant packet header information. Thus the data that appears here is in the form of binary tables preceded by binary headers, nearly identical to how they were presented in the original packetized data but without the length restriction imposed on the packets. The intention is that this archive is the primary repository of all primary data, but that most users will reference RDR products in more accessible formats. The MECA Non-Imaging EDR data products were generated by the MIPL (Multimission Image Processing Laboratory) at JPL. The MECA subsystem contains no independent memory, and all MECA data is stored in Phoenix ROM or flash memory until it can be transmitted to an orbital relay. Lander to orbiter bandwidth is limited, and there is typically no retransmission of data. Data ==== Each MECA Non-Imaging EDR consists of a single file containing binary data preceded by an ASCII PDS label. The body of the file is a binary data set consisting of one of sixteen format types as described in the Software Interface Specification. Types 0-3 contain data pertinent to an AFM measurement; the actual scan data is a table in type 2. Types 4-6 are data returned by common electronics functions, including power monitoring (type 5). Type 7 contains all the TECP data. Types 8-15 pertain to the WCL: Type 8 contains data from all the potentiometric WCL sensors such as pH and ion-selective electrodes; type 9 contains conductivity data; types 10-14 contains various voltammetries and potentiometries, all in a common format; and type 15 contains pressure and temperature data. Software ======== Data reduction software for the MECA Non-Imaging EDRs is coded in the Matlab programming environment (Mathworks, Inc.) Matlab is a privately maintained, closed source language that does not conform to an industry standard, and consequently it has been decided not to include the Matlab code as part of the PDS archive. The Matlab scripts may be obtained free of charge by contacting members of the MECA science team. Media/Format ============ The data set will stored and distributed online. These data are available on-line from the Planetary Data System (PDS) at:

Alternate Names



  • Planetary Science: Geology and Geophysics

Additional Information



Questions and comments about this data collection can be directed to: Dr. David R. Williams



NameRoleOriginal AffiliationE-mail
Dr. Michael H. HechtData ProviderNASA Jet Propulsion
Dr. Michael H. HechtGeneral ContactNASA Jet Propulsion
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