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

Data Set Overview ================= The Thermal Evolved Gas Analyzer (TEGA) is designed to analyze ~50 mg of fine grained Martian soil or rock fragments. TEGA consists of four basic components: a soil delivery system, an oven/calorimeter thermal analyzer (TA), a gas storage and handling system, and a mass spectrometer acting as an evolved-gas analyzer (EGA). A full description of the TEGA instrument can be found in [BOYNTONETAL2008]. The data set PHX MARS THERMAL EVOLVED GAS ANALYZER 3 RDR is a time series collection of TA, EGA, engineering, and commanding measurements from the TEGA aboard the Mars Phoenix Lander. The RDR data are converted from the EDR raw values to scientifically useful data including physical units. Data types included in this data set are engineering data, calorimeter data from the TA,sweep mode EGA data, and mass hopping mode EGA data. Data are sorted by time, with each data file containing one measurement day's worth of data from midnight to midnight UTC. TEGA is designed to analyze 8 individual Martian regolith samples, one sample in each of the eight single use ovens. The EGA portion of the instrument will not only analyze the gases evolved from the samples heated in the ovens, but will also analyzed samples of the Martian atmosphere. TEGA is expected to operate for 45 days. During operations science, engineering and housekeeping data are downloaded from the lander by the Jet Propulsion Laboratory (JPL) into the Telemetry Data System(TDS). The TDS sends data to a process that translates data packets and examines instrument health via messages. Data are output to a spooler that passes them to the University of Arizona (UA) database ingest process. The ingest process inputs raw data into the UA database. Data are retrieved from the UA database to build the TEGA RDR data products. The TEGA RDR data set is intended to be the first reduced data product for the TEGA instrument. It should be useful to those scientists who are experienced in calorimetry and mass spectrometry. Parameters ========== The TEGA RDR data set is composed of four data types. The objective of compiling the TEGA RDR is to create a record of of data that has been converted to scientifically useful physical units and has been combined with useful calibration information. The following paragraphs discuss the parameters of interest in each of the data types. SCRDR ----The SC data are time series records taken over the course of a measurement day. Data files are labeled with the date. Individual records are a single data collection interval. SC data are the science data produced by the TA. EGSRDR -----The EGA data are time series records taken over the course of a measurement day. Data files are labeled with the date. Individual records are a single data collection interval. EGA data are the science data produced by the EGA mass spectrometer in sweep mode. EGHRDR -----The EGH data are time series records taken over the course of a measurement day. Data files are labeled with the date. Individual records are a single data collection interval. EGH data are the science data produced by the EGA mass spectrometer in mass hopping mode. ENGRDR -----The Engineering data are time series records for each engineering parameter taken over the course of a measurement day. Data files are grouped in the ENG folder and are labeled with the engineering parameter name. Individual records are a single data collection interval that is variable in duration. Engineering values are reported by parameter name and include collection time, and parameter value. In general, temperatures are reported in Celsius, currents in milliamps, and potentials in volts. The ENGRDR label file is the definitive source for the units of measure. Engineering values are specific monitor values recorded by TEGA. Processing ========== TEGA data (both science and engineering) are downloaded from the Phoenix Mars Lander by JPL into the Telemetry Data System (TDS). The TDS sends the data to a process called TEGA_tl, that translates GRS packets from any source to any destination and examines instrument health via messages. The data are checked for packet types, header information, messages, or errors. Data are output to a spooler, which passes data to the UA database ingestion process. The ingestion process inputs raw telemetry data into the database. A function reads the data header to get the total number of bytes in the packet, and the sequence bytes. The rest of the packet is then read. The data type, read from the common header, is returned, determining the next step in the processing. One of a number of different procedures is run to insert packet data into the appropriate database tables. If the data type returned is less than or equal to 0 an error message is returned stating that the packet was not inserted. The initialization of the ingestion process also sets up the necessary connections to the SPICE kernel information (Navigation and Ancillary Information Facility (NAIF) system designed to provide scientists with ancillary observation geometry data useful in interpretation of science instrument observations returned from planetary spacecraft), the database, and the input data. The appropriate SPICE kernels are loaded and opened, and a connection is initiated with the database. SPICE kernels are used to compute the local solar time of the measurements from the spacecraft or instrument clock times. As engineering values are entered into the database, stored database procedures are called to convert raw engineering DN values into physical units. The raw DN values are converted using stored polynomials unique to each engineering parameter.. The polynomials were derived through hardware calibrations, see the TEGA RDR SIS Appendix 7.3 for a table of the engineering conversions. Data ==== The TEGA RDR data set is composed of a series of date stamped files that contain 1 day's worth (24 hours, 00:00:00 UTC to 23:59:59 UTC) of data for 4 different data types. The following sections describe each data type. SCRDR ----SC data are composed of scanning calorimeter data. These data are composed of data collection time and oven and sheild temperature and duty cycle data. EGSRDR -----EGSRDR data are mass spectrometer data collected in sweep mode. These data are composed of timing, mass spectrometer emission, temperature and voltage parameters, as well as detector counts at each of the four detectors. EGHRDR -----EGHRDR data are mass hopping mode EGA data. These data include start and stop times for the collection, voltage, emission energy and level, and counts at the detector. ENGRDR -----Engineering data are composed of the 84 different engineering readings monitored in TEGA. ENGRDR data is composed of collection time information and engineering value. The following is a list of all the engineering readings and a description of each. TA_MANIFOLD_PRES Manifold Pressure TA_PLUS_5_VREF +5V REF TA_OUTLET_PRES Outlet Pressure TA_MANIFOLD_TEMP TA Manifold Temperature TA_EGA_PLUMB_TEMP MS Plumbing Temperature TA_EGA_BAKEOUT_TEMP Bakeout temperature TA_PLUMBING_1_TEMP Plumbing 1 Temperature TA_PLUMBING_2_TEMP Plumbing 2 Temperature TA_EGA_MAN_TEMP MS Manifold Temperature TA_CAL_TANK_TEMP Cal Tank Temperature TA_CPU_TEMP CPU Temperature TA_PWR_SPLY_1_TEMP Power Supply 1 Temperature TA_PWR_SPLY_2_TEMP Power Supply 2 Temperature TA_PWR_CNTL_1_TEMP Power Control 1 Temperature TA_PWR_CNTL_2_TEMP Power Control 2 Temperature TA_A2D_TEMP ADC Temperature TA_COVER_1_TEMP cover 1 temperature TA_INPUT_FUNNEL_1_LO_TEMP Funnel 1 Temperature TA_PRES_SENSE_FD_BK Pres Sense Exc. Feedback TA_INPUT_FUNNEL_2_LO_TEMP Funnel 2 Temperature TA_OVEN_TEMP Oven Temperature TA_SHLD_TEMP Shield Temperature TA_EGA_ELECT_BOX_TEMP TEB Temperature TA_T_HEATER_TEMP 'T' Heater Temperature TA_TRANS_TUBE_TEMP Transfer Tube Temperature TA_EGA_GEC_TEMP GEC Temperature TA_BUS_A_VOLT Bus A Voltage TA_AGD_0_1 AGD_0_3 ground TA_AGD_3_1 AGD_3_1 ground TA_CPU_PLUS_5_VOLT CPU Voltage TA_ANLG_PLUS_12_VOLT Analog +12V Voltage TA_ANLG_MINUS_12_VOLT Analog -12V Voltage TA_OVEN_PLUS_15_VOLT Oven Voltage TA_SHIELD_PLUS_30_VOLT Shield Voltage TA_BUS_A_CUR Bus A Current TA_BUS_B_CUR Bus B Current TA_EGA_CUR EGA Current TA_CPU_PLUS_5_CUR CPU Current TA_ANLG_PLUS_12_CUR Analog +12V Current TA_ANLG_MINUS_12_CUR Analog -12V Current TA_OVEN_PLUS_15_CUR Oven Current TA_SHIELD_PLUS_30_CUR Shield Current TA_FULL_DETECT Full Detect Integrated TA_FULL_DETECT_RAW Full Detect Raw TA_OVEN_ERR Oven Error TA_SHLD_ERR Shield Error TA_CAL_TANK_COLD_TEMP Cal Tank Cold Temperature TA_COVER_2_TEMP cover 2 Temperature MEM_OVEN_INT_LO Oven integrator val lo bytes MEM_OVEN_INT_HI Oven integrator val hi bytes MEM_SHLD_INT_LO Shield integrator val lo bytes MEM_SHLD_INT_HI Shield integrator val hi bytes MEM_OVEN_VOLT Oven voltage MEM_OVEN_CUR Oven current MEM_SHLD_VOLT Shield voltage MEM_SHLD_CUR Shield current MEM_MANIFOLD_PRES Manifold pressure MEM_OVEN_ERR Oven error MEM_SHLD_ERR Shield error MEM_T_WIDTH T pulse width COVER1_DONE Cover1 Limit Switch COVER2_DONE Cover2 Limit Switch MEM_OVEN_WIDTH Oven pulse width MEM_SHLD_WIDTH Shield pulse width EGA_STATUS_BITS Status bits value EGA_TRAP_CUR Trap current monitor EGA_EMISSION_CUR Emission current monitor EGA_FILAMENT_1 Filament 1 in use EGA_FILAMENT_2 Filament 2 in use EGA_PLUS_5_VOLT +5 volt monitor EGA_PLUS_12_VOLT +12 volt monitor EGA_MINUS_12_VOLT -12 volt monitor EGA_FILAMENT_CUR_1 Filament 1 current monitor EGA_FILAMENT_CUR_2 Filament 2 current monitor EGA_MULTIPLIER_VOLT Multiplier voltage monitor EGA_ION_PUMP_VOLT Ion Pump voltage monitor EGA_ION_PUMP_CUR Ion Pump Current monitor EGA_SWEEP_VOLT Sweep voltage monitor EGA_GEC_CUR GEC current monitor EGA_MAGNET_TEMP_1 Magnet 1 temperature EGA_MAGNET_TEMP_2 Magnet 2 temperature EGA_PROC_TEMP CPU temperature EGA_AVG_CALLS Average # calls to Task Queue EGA_MIN_CALLS Minimum # calls to Task Queue EGA_SPARE_3 Spare EGA_SPARE_4 Spare Ancillary Data ============== No ancillary data are included with this data set. Coordinate System ================= Several coordinate systems are used by the Phoenix project. A detailed description can be found in the TEGA RDR SIS document found in the Documents directory. Software ======== No TEGA specific software is provided with this data set. PDS-labeled images and tables can be viewed with the program NASAView, developed by the PDS and available for a variety of computer platforms from the PDS web site There is no charge for NASAView. Media/Format ============ The TEGA RDR will be delivered using DVD media. Formats will be based on standards for such products established by the Planetary Data System (PDS) [PDSSR2001]. 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. William V. BoyntonData ProviderUniversity of
Dr. William V. BoyntonGeneral ContactUniversity of
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