The Mars Express PFS data set contains raw (CODMAC Level 2) measurements from the Planetary Fourier Spectrometer collected during the first extension Mars orbit phases.
Description
Data Set Overview ================ The Mars Express (MEX) Planetary Fourier Spectrometer (PFS) Data Archive is a collection of raw data collected during the MEX Mission to Mars. For more information on the investigations proposed see the PFS documentations in the DOCUMENT/ folder. This data set was collected during the MEX Mission phases: - First Extension Mission Phase Mission Phase Definition ======================== It should be noted that the Mars Express (MEX) Planetary Fourier Spectrometer (PFS) group uses mission phases which deviate from the ones defined in the MISSION.CAT files given by ESA in order to keep the keywords and abbreviations consistent for Mars Express, Venus Express and Rosetta. Those mission phase abbreviations are also used in the data description field of the dataset_id. MaRS mission name | abbreviation | time span ================================================================ Near Earth Verification | NEV | 2003-06-02 - 2003-07-31 ---------------------------------------------------------------Interplanetary Cruise | IC | 2003-08-01 - 2003-12-25 ---------------------------------------------------------------Nominal Mission | Nominal | 2003-12-26 - 2005-11-30 ---------------------------------------------------------------First Extension Mission | EXT1 | 2006-01-01 - 2007-09-30 ---------------------------------------------------------------Second Extension Mission| EXT2 | 2007-10-01 - 2009-12-31 ---------------------------------------------------------------Data files ---------Data files are: The tracking files from Deep Space Network (DSN) and from the Intermediate Frequency Modulation System (IFMS) used by the ESA ground station New Norcia. Level 1b data are archived. The Geometry files All Level binary data files will have the file name extension eee = .DAT Data levels ---------It should be noted that these data levels which are also used in the file names and data directories are PSA data levels whereas in the PDS label files CODMAC levels are used. PSA data level | CODMAC level ----------------------------1a | 1 1b | 2 2 | 3 Data Set Identifier ------------------The DATA_SET_ID is a unique alphanumeric identifier for the data sets. The PFS data set ID is generated using the follow syntax: ------V Acronym | Description -------------------------------------------------------------------- | MEX this is fixed, and is the mission ID for | Mars Express. -------------------------------------------------------------------- | M this is fixed, and refers to the target of Mars -------------------------------------------------------------------- | PFS this is fixed and identifies the instrument | as PFS (Planetary Fourier Spectrometer) --------------------------------------------------------------------| 2 this number indicates the level of processing | the data has undergone on the CODMAC scale -------------------------------------------------------------------- | EDR this represents the type of data in the data | set. For the standard PFS deliveries, this will | always be set to EDR meaning Experimental Data | Record -------------------------------------------------------------------- | this is a descriptive secion of the ID and will | typically refer to the mission phase ID or an | orbital range for the nominal mission. Values are: | | NOMINAL nominal mission phase. | EXT1 first extended mission phase. | EXT2 second extended mission phase. -------------------------------------------------------------------- | <1.0> this is the version of the data set, | starting at 1.0 and increasing incrementally if | changes are made to the products or the dataset | itself. --------------------------------------------------------------------When all of this is put together, it provides a data set ID of the form MEX-M-PFS-2-EDR-NOMINAL-V1.0 or MEX-M-PFS-2-EDR- EXT1-V1.0 VOLUME -----The VOLUME_SET_ID follows a strict formation rule defined in 1, section 19.5.1, with the Country > IT for Italy Government Branch > CNR Discipline within government branch > IFSI mission and instrument ID > MEXPFS and a 4-digit sequence number > 1001 For the number, the first digit represents the VOLUME_SET and the last number the VOLUME within the VOLUME_SET. Descriptive files ----------------Descriptive files contain information in order to support the processing and analysis of data files. The following file types are defined as descriptive files with extension eee = .LBL PDS label files .TXT Information (text) files Data Directory Naming Convention and Structure =============================================== Inside the DATA directory, the data products are organized into several subdirectories. The structure of the directories will depend upon the phase of the mission in the dataset. IC and NEV ========== During the Near Earth Verification (NEV) and Interplanetary Cruise (IC) phases of the mission, PFS only took measurements of the internal calibration source (Internal Black Body and Lamp) and of deep space. The limited number of observations are simply divided by sensor into the following directory structure: DATA | |-NEV | |- LWC Long Wave detector | |- SWC Short Wave detector Nominal and Extended Mission ============================ For the nominal and extended mission phases at Mars, data will be split into groups of 10 orbits, whith the following syntax: The base directory will be MARS as all products from these phases will be from the planet. Beneath this, data will be separated into observations from the long-wave (LWC) and short-wave (SWC) sensors. Finally, data will be divided into blocks of 10 orbits using the following taxonomy: ORBX Acronym | Description --------------------------------------------------------------------ORB | This is fixed and means ORBIT -------------------------------------------------------------------- | This will be the first 3 digits of all orbits contained | in this directory --------------------------------------------------------------------X | This is fixed and means that inside this directory are data | from orbits YYY0 to YYY9. --------------------------------------------------------------------For example, the directory ORB000X will contain all products from orbit 0001 to 0009. The DATA subdirectory structure for the nominal mission data will therefore follow the scheme: DATA | |-NEV | | | |-LWC | |-SWC | |- IC | |-LWC | |-SWC | |-MARS | | | |-LWC | | |-ORB001X | | |-ORB002X | | | |-SWC | | |-ORB001X | | |-ORB002X File naming Convention ====================== The data products are identified principally by orbit numer and detector type, following the scheme: PFS____. Orbit number. For the Near Earth Verification and Interplanetary Cruise Phase the field is substituted with the name of the Phase and Sub-phase as : = . For the files in the CALIB/ directory the field is substitute with the field, Responsivity or Deep Space observation, and the field, Forward or Reverse pendulum motion, as: = _ -------------------------------------------------------------------- | IC for Interplanetary Cruise Phase | NEV for Near Earth Verification Phase -------------------------------------------------------------------- | C Check Out Sub-phase | D Dry Earth Sub-phase | E Earth Moon Sub-phase (Observation to Earth and Moon) | 1 PS001 Sub-phase (First Switch ON) | 2 PS002 Sub-phase (Calibration) | 3 PS003 Sub-phase (DTM, Pericenter Pass Simulation , | Calibration) | 4 PS004 Sub-phase (FOV, Calibration) | 5 PS005 Sub-phase (Calibration, heating of SW detector) | S Star Calibration Sub-phase | M Mars Crossing Sub-phase | | all the sub-phases reffer to specific PFS test | operation performed during the NEV phases. -------------------------------------------------------------------- | Defines if the instrument is in calibration mode or | in measurement mode: | | CAL Calibration | MEAS Measurement | | For the HK file field is referred to the | corrisponding RAW file field. -------------------------------------------------------------------- | indicates the type of data provided: RAW-HK-RAD | | RAW contains interferogram | HK contains the HK information about PFS during the | acquisition | RAD contains radiance spectra (calibrated data only) -------------------------------------------------------------------- | defines the type of the detector used for the | interferogram acquisition: Short wavelength (SW) or Long | wavelength (LW). -------------------------------------------------------------------- | the extension depends on the type of file (LBL for a | label file, DAT for the data product associated with | the label) --------------------------------------------------------------------For Mars: PFS_0010_ MEAS_HK_SW.LBL PFS_0010_ MEAS_HK_SW.DAT would be a PFS product from Mars orbit 0010. It would be a raw calibration data product from the short wavelength sensor with its associated label. For the Near Earth Verification and Interplanetary Cruise Phase: PFS_NEV1_MEAS_HK_SW.DAT PFS_NEV1_MEAS_HK_SW.LBL would be a PFS product from the PS001 Sub-phase of the Near Earth Verification phase. It would be a raw calibration product from the short wavelength sensor with its associated label. PFS_IC_CAL_HK_SW.DAT PFS_IC_CAL_HK_SW.LBL would a PFS product from the Check Out sub-phase of the Interplanetary Cruise. It would be a raw calibration product from the long wavelength sensor with its associated label. Ancillary Data - EXTRAS ====================== The EXTRAS directory contains items that may be useful to a user, but are non-essential for the use of the data in the PFS data sets and are not essential for the PSA or compliance to the PDS Standards. The contents of the EXTRAS directory do not need to conform to PDS standards, and all files within this directory are produced and presented by the PFS team. In the PFS EXTRAS directory is a file that describes any special features of a given orbit. For example, any specific scientific objectives targeted, special events that occurred or tests that were completed for a given orbit are listed in this file. The file is presented in ASCII format. Software ======== PFS software (IDL version) febrary 2007 When downloading a ZIP file, the user should put it in a working directory dedicated to PFS software,then unzip it. This will create a two subdirectory : /SOFTWARE/ | |- /CALIB/ | |- /DATA/ | |- /GEOMETRY/ The essential functions to open and read the data are in the FUNCTIONS subdirectory of each directory. The examples programs given in both DATA and GEOMETRY are intended only as reader of the PFS data. The CALIB subdirectory contains both the programs to read calibrated PFS spectra stored in the /CALIB_SAMPLE/ directory at root level and the code to produce that outputs starting from the RAW data and the calibration tables stored in the /CALIB / directory at root level. Essentially the software in the /SOFTWARE/CALIB/CALIBRATOR/ use the same functions stored in the /SOFTWARE/CALIB/DATA/ to read raw data, then read the right calibration tables and apply the calibration operation to obtain the calibrated spectra (further details should be found in the calibration documents PFS_LWC_CALIB.PDF and PFS_SWC_CALIB.PDF as well in the PFS_CAL_LAB_1.PDF , PFS_CAL_LAB_2.PDF and PFS_CAL_NEAREARTH.PDF, in the /DOCUMENT/ directory). To run example code do the following steps: - open a .PRJ file (for DATA or for GEOMETRY) - change the PATH variable to your PFS Data directory - Project > Compile > All Files - Project > Run Only for the software stored in the /CALIBRATOR/ subdirectory, the last step must be substituted with : - Run > Run program_name The LWC_CAL.pro, SWC_CAL_LASER-OFF.pro and SWC_CAL_LASER-ON.pro will give to the user the calibrated spectra calculated directly from the raw data and from the calibration tables. --------Function and Resulting Variables -------read_pfs_data(FILE,NUM,RECORDS): return a structured variable array whith the data. Array lenght is NUM. Each array element is defined as : OBT_OBSERVATION_TIME : DOUBLE PRECISION FLOAT SCET_OBSERVATION_TIME : UNSIGNED LONG INTEGER INTERFEROGRAM : INTEGER ARRAY WHITH LENGHT : RECORDS INPUT: FILE : path of the data file to open NUM : total number of the field (: observation) stored in the file RECORDS : length of a single interferogram -------read_pfs_hk(FILE,NUM): return a structured variable array whith the housekeeping data. Array lenght is NUM. Each array element is defined as : OBT_OBSERVATION_TIME : DOUBLE PRECISION FLOAT SCET_OBSERVATION_TIME : UNSIGNED LONG INTEGER TypeOfMes : UNSIGNED LONG INTEGER SD_Version : UNSIGNED LONG INTEGER ZOPD_SW_FWD : UNSIGNED LONG INTEGER ZOPD_SW_REV : UNSIGNED LONG INTEGER ZOPD_LW_FWD : UNSIGNED LONG INTEGER ZOPD_LW_REV : UNSIGNED LONG INTEGER SCANPOS : UNSIGNED LONG INTEGER SW_ZeroX_Cutoff_Status : DOUBLE PRECISION FLOAT LW_ZeroX_Cutoff_Status : DOUBLE PRECISION FLOAT SPEEDCLOCK_Status : DOUBLE PRECISION FLOAT ADCCLOCK_Status : DOUBLE PRECISION FLOAT SW_Detector_Cutoff_Status : DOUBLE PRECISION FLOAT LW_Detector_Cutoff_Status : DOUBLE PRECISION FLOAT SWGAIN_Status : UNSIGNED LONG INTEGER LWGAIN_Status : UNSIGNED LONG INTEGER First_ADC_1_Status : UNSIGNED LONG INTEGER Second_ADC_1_Status : UNSIGNED LONG INTEGER First_ADC_2_Status : UNSIGNED LONG INTEGER Second_ADC_2_Status : UNSIGNED LONG INTEGER Select_Motor_Coil_Status : UNSIGNED LONG INTEGER DPDIR_Status : UNSIGNED LONG INTEGER SW_ZOPD_Position : UNSIGNED LONG INTEGER LW_ZOPD_Position : UNSIGNED LONG INTEGER Right_Collisions : UNSIGNED LONG INTEGER Left_Collisions : UNSIGNED LONG INTEGER SWLASERPWR_10V : DOUBLE PRECISION FLOAT LWLASERPWR_10V : DOUBLE PRECISION FLOAT SWPHOTODIODEPWR_10V : DOUBLE PRECISION FLOAT LWPHOTODIODEPWR_10V : DOUBLE PRECISION FLOAT T1_10V : DOUBLE PRECISION FLOAT T2_10V : DOUBLE PRECISION FLOAT T3_10V : DOUBLE PRECISION FLOAT T4_10V : DOUBLE PRECISION FLOAT T5_10V : DOUBLE PRECISION FLOAT T6_10V : DOUBLE PRECISION FLOAT T7_10V : DOUBLE PRECISION FLOAT T8_10V : DOUBLE PRECISION FLOAT LDTEMPSW_10V : DOUBLE PRECISION FLOAT LDTEMPLW_10V : DOUBLE PRECISION FLOAT SWTEMP_10V : DOUBLE PRECISION FLOAT LWTEMP_10V : DOUBLE PRECISION FLOAT TEMPA1_10V : DOUBLE PRECISION FLOAT TEMPA2_10V : DOUBLE PRECISION FLOAT SWTRW_10V : DOUBLE PRECISION FLOAT LWTRW_10V : DOUBLE PRECISION FLOAT CLVOLTAGE_10V : DOUBLE PRECISION FLOAT INPUT: FILE : path of the data file to open NUM : total number of the field (: observation) stored in the file -------read_pfs_label(FILE,NAME): return value stored in a PDS label file in the NAME field INPUT: FILE : path of the label file to open NAME : name if the fiel to search for (i.e. ROWS or FIELDS) -------reader_geometry(FILE,NUM): return a structured variable array whith all the geometrical information.Array lenght is NUM. Each array element is defined as : SCET : DOUBLE PRECISION FLOAT LONGITUDE : DOUBLE PRECISION FLOAT LATITUDE : DOUBLE PRECISION FLOAT SPACECRAFT_ALTITUDE : DOUBLE PRECISION FLOAT Local_Time : SINGLE PRECISION FLOAT Solar_Longitude : DOUBLE PRECISION FLOAT INCIDENC_EANGLE : SINGLE PRECISION FLOAT EMISSION_ANGLE : SINGLE PRECISION FLOAT PHASE_ANGLE : SINGLE PRECISION FLOAT MOLA_ALTIMETRY : SINGLE PRECISION FLOAT LW_TANGENT_ALTITUDE : SINGLE PRECISION FLOAT LW_TARGET_DISTANCE : SINGLE PRECISION FLOAT SOLAR_DISTANCE : SINGLE PRECISION FLOAT SUBSOLAR_LONGITUDE : DOUBLE PRECISION FLOAT SUBSOLAR_LATITUDE : DOUBLE PRECISION FLOAT PLANETARY_PHASE_ANGLE : SINGLE PRECISION FLOAT SUB_SPACECRAFT_LONGITUDE : DOUBLE PRECISION FLOAT SUB_SPACECRAFT_LATITUDE : DOUBLE PRECISION FLOAT JULIAN_DATE : DOUBLE PRECISION FLOAT AIR_MASS : SINGLE PRECISION FLOAT INPUT: FILE : path of the geometry file to open NUM : total number of the field (: observation) stored in the file Definiton of field in Geometry File: -----------------------------------------------------------------Label | Description | Range | Units -----------------------------------------------------------------SCET | Value of the Spacecraft clock | | LONG_LW | Mars Longitude for the LWC | -180/+180 | deg LAT_LW | Mars Latitude for the LWC | - 90/+ 90 | deg LONG_SW | Mars Longitude for the SWC | -180/+180 | deg LAT_SW | Mars Latitude for the SWC | - 90/+ 90 | deg | The Longitudes are expressed | | following the Eastward convention | | SC_ALT | Spacecraft altitude | | km LT | Local Time at the SWC target | |hours LS | Solar Longitude | 0/+360 | deg INC_SW | Incidence angle for the SWC | 0/+180 | deg EM_SW | Emission angle for the SWC | 0/+180 | deg PH_SW | Phase angle for the SWC | 0/+180 | deg ALTM | Mola Altimetry | | m TG_ALT | Limb altitude for the SWC | | km | This parameter is not null only | | | for limb observations | | TG_DIST | Distance from the spacecraft to | | km | the target point (SWC) | | S_DIST | Solar distance | | au SS_LONG | Longitude of the sub-solar point | -180/+180 | deg SS_LAT | Latitude of the sub-solar point | - 90/+ 90 | deg PL_PH | Planetary phase angle | 0/+180 | deg SSC_LONG | Longitude of the sub-spacecraft | -180/+180 | deg SSC_LAT | Latitude of the sub-spacecraft | - 90/+ 90 | deg JD | Julian Date | | Airmass | Secant of the emission angle | | ------------------------------------------------------------------------read_pfs_data_calib(FILE,NUM,RECORDS): return a structured variable array whith the data. Array lenght is NUM. Each array element is defined as : OBT_OBSERVATION_TIME : DOUBLE PRECISION FLOAT SCET_OBSERVATION_TIME : DOUBLE PRECISION FLOAT WAVENUMBER : DOUBLE PRECISION ARRAY WHITH LENGHT : RECORDS RADIANCE : DOUBLE PRECISION ARRAY WHITH LENGHT : RECORDS INPUT: FILE : path of the data file to open NUM : total number of the field (: observation) stored in the file RECORDS : length of a single spectra, the same for the WAVENUMBER and RADIANCE fields. -------Documents ============ Documents directory contains all of the Flight user manual documents, which have been divided into 9 chapters, describing in detail all of the features of the experiment. In addition, the ICD (this document) is provided also in ASCII format, and papers describing the calibration procedures for PFS are provided. A complete list and a short description: --------------------------------------------------------------------Name | Description --------------------------------------------------------------------DOCINFO.TXT | DOCUMENTS directory content list --------------------------------------------------------------------CALIBR_REPORTS_LONG_TERM.TXT| Calibration Reports, warnings on | Calibration and long term calibration | notes. --------------------------------------------------------------------CALIBR_REPORTS_LONG_TERM.LBL| Label file for the Calibration Reports --------------------------------------------------------------------CALIB_SAMPLES_NOTE.TXT | Reports on how to obtain the files in | CALIB_SAMPLES/ from the RAW data. --------------------------------------------------------------------CALIB_SAMPLES_NOTE.LBL | Label file for the Calibration notes. --------------------------------------------------------------------MEX-PFS-PSA-ICD-24.ASC | Interface Control Document in ASCII --------------------------------------------------------------------MEX-PFS-PSA-ICD-24.LBL | Label file for Interface Control Document --------------------------------------------------------------------MEX-PFS-PSA-ICD-24.PDF | Interface Control Document in Portable | Document Format --------------------------------------------------------------------MEX-PFS-PSA-ICD_FIG_1.PNG | ICD figure 1 - Pfs optical scheme --------------------------------------------------------------------MEX-PFS-PSA-ICD_FIG_2.PNG | ICD figure 2 - Data acquisition and | processing scheme --------------------------------------------------------------------MEX-PFS-PSA-ICD_FIG_3.PNG | ICD figure 3 - High level directory | structure --------------------------------------------------------------------MEX-PFS-PSA-ICD_FIG_4.PNG | ICD figure 4 -DATA directory structure --------------------------------------------------------------------MEX_ORIENTATION_DESC.LBL | Label file for Mars express spacecraft | orientation --------------------------------------------------------------------MEX_ORIENTATION_DESC.TXT | Mars express spacecraft orientation --------------------------------------------------------------------PFS_CAL_LAB_1.LBL | Label fi le for Internal Note on Pfs | Calibration - Volume I --------------------------------------------------------------------PFS_CAL_LAB_1.PDF | Internal Note on Pfs Calibration - I --------------------------------------------------------------------PFS_CAL_LAB_2.LBL | Label file for Internal Note on Pfs | Calibration - Volume I --------------------------------------------------------------------PFS_CAL_LAB_2.PDF | Internal Note on Pfs Calibration - I --------------------------------------------------------------------PFS_CAL_NEAREARTH.LBL | Label file for Internal Note on Pfs | Calibration in Space --------------------------------------------------------------------PFS_CAL_NEAREARTH.PDF | Internal Note on Pfs Calibration in Space --------------------------------------------------------------------PFS_LWC_CALIB.LBL | Label file for LWC channel Calibration --------------------------------------------------------------------PFS_LWC_CALIB.PDF | LWC channel Calibration --------------------------------------------------------------------PFS_MEX_FUM.LBL | Label file for FUMs Index --------------------------------------------------------------------PFS_MEX_FUM.PDF | FUMs Index --------------------------------------------------------------------PFS_MEX_FUM1.LBL | Label file for FUM 1 - Instrument | description --------------------------------------------------------------------PFS_MEX_FUM1.PDF | FUM 1 - Instrument description --------------------------------------------------------------------PFS_MEX_FUM2.LBL | Label file for FUM 2 - Instrument | performance budgets --------------------------------------------------------------------PFS_MEX_FUM2.PDF | FUM 2 - Instrument performance budgets --------------------------------------------------------------------PFS_MEX_FUM3.LBL | Label file for FUM 3 - Instrument | software and memory map --------------------------------------------------------------------PFS_MEX_FUM3.PDF | FUM 3 - Instrument software and memory | map --------------------------------------------------------------------PFS_MEX_FUM4.LBL | Label file for FUM 4 - Housekeeping | information --------------------------------------------------------------------PFS_MEX_FUM4.PDF | FUM 4 - Housekeeping information --------------------------------------------------------------------PFS_MEX_FUM5.LBL | Label file for FUM 5 - Operating, | non-operating conditions and interfaces --------------------------------------------------------------------PFS_MEX_FUM5.PDF | FUM 5 - Operating, non-operating conditions | and interfaces --------------------------------------------------------------------PFS_MEX_FUM7.LBL | Label file for FUM 7 - Instrument operation | manual --------------------------------------------------------------------PFS_MEX_FUM7.PDF | FUM 7 - Instrument operation manual --------------------------------------------------------------------PFS_MEX_FUM8.LBL | Label file for FUM 8 - Science operations --------------------------------------------------------------------PFS_MEX_FUM8.PDF | FUM 8 - Science operations --------------------------------------------------------------------PFS_MEX_FUM9.LBL | Label file for FUM 9 - Tm_tc interface | data base --------------------------------------------------------------------PFS_MEX_FUM9.PDF | FUM 9 - Tm_tc interface data base --------------------------------------------------------------------PFS_ON_MARS_EXPRESS.LBL | Label file for Instruments description --------------------------------------------------------------------PFS_ON_MARS_EXPRESS.PDF | Instruments description --------------------------------------------------------------------PFS_SWC_CALIB.LBL | Label file for SWC channel Calibration --------------------------------------------------------------------PFS_SWC_CALIB.PDF | SWC channel Calibration ---------------------------------------------------------------------
Instrument
PFS
Temporal Coverage
2003-06-23T00:00:00Z/2005-12-31T00:00:00Z
Version
V1.0
Mission Description
Mission Overview ================ Mars Express was the first flexible mission of the revised long-term ESA Science Programme Horizons 2000 and was launched to the planet Mars from Baikonur (Kazakhstan) on June 2nd 2003. A Soyuz-Fregat launcher injected the Mars Express total mass of about 1200 kg into Mars transfer orbit. Details about the mission launch sequence and profile can be obtained from the Mission Plan (MEX-MMT-RP-0221) and from the Consolidated Report on Mission Analysis (CREMA)(MEX-ESC-RP5500). The mission consisted of (i) a 3-axis stabilized orbiter with a fixed high-gain antenna and body-mounted instruments, and (ii) a lander named BEAGLE-2, and was dedicated to the orbital and in-situ study of the interior, subsurface, surface and atmosphere of the planet. After ejection of a small lander on 18 December 2003 and Mars orbit insertion (MOI) on 25 December 2003, the orbiter experiments began the acquisition of scientific data from Mars and its environment in a polar elliptical orbit. The nominal mission lifetime for the orbiter was 687 days following Mars orbit insertion, starting after a 5 months cruise. The nominal science phase was extended (tbc) for another Martian year in order to complement earlier observations and allow data relay communications for various potential Mars landers up to 2008, provided that the spacecraft resources permit it. The Mars Express spacecraft represented the core of the mission, being scientifically justified on its own by investigations such as high- resolution imaging and mineralogical mapping of the surface, radar sounding of the subsurface structure down to the permafrost, precise determination of the atmospheric circulation and composition, and study of the interaction of the atmosphere with the interplanetary medium. The broad scientific objectives of the orbiter payload are briefly listed thereafter and are given more extensively in the experiment publications contained in ESAs Special Publication Series. See NEUKUM&JAUMANN2004, BIBRINGETAL2004, PICARDIETAL2004, FORMISANOETAL2004, BERTAUXETAL2004, PAETZOLDETAL2004 and PULLANETAL2004. The Mars Express lander Beagle-2 was ejected towards the Mars surface on 19 December 2003, six days before the orbiters capture manoeuvre. The probe mass was limited to about 70 kg by the mission constraints, which led to a landed mass of 32 kg. The complete experimental package was weighed in approximately at 9kg. The landers highly integrated scientific payload was supposed to focus on finding whether there is convincing evidence for past life on Mars or assessing if the conditions were ever suitable. Following safe landing on Mars, this lander mission would have conducted dedicated studies of the geology, mineralogy, geochemistry, meteorology and exobiology of the immediate landing site located in Isidis Planitia (90.74?E, 11.6?N), as well as studies of the chemistry of the Martian atmosphere. Surface operations were planned to last about 180 sols or Martian days ( about 6 months on Earth), see SIMSETAL1999. As no communication could be established to the BEAGLE-2 lander, it was considered lost in February 2004 after an extensive search. A nominal launch of Mars Express allowed the modify the orbit to a G3-ubeq100 orbit. The G3-ubeq100 orbit is an elliptical orbit, starting with the sub-spacecraft point at pericentre at the equator and a sun ^ation of 60 degrees. At the beginning of the mission, the pericentre moves southward with a shift of 0.54 degree per day. At the same time the pericentre steps towards the terminator which will be reached after about 4 months, giving the optical instruments optimal observing conditions during this initial period. Throughout this initial phase lasting until midMay 2004, the downlink rate will decrease from 114 kbit/s to 38 kbit/s. After an orbit change manoeuvre on 06 May 2004 the pericentre latitude motion is increased to guarantee a 50/50 balance between dayside and nightside operations. With this manoeuvre, the apocentre altitude is lowered from 14887 km to 13448 km, the orbital period lowered from ~7.6 hours to 6.645 hours, and the pericentre latitude drift slightly increased to 0.64 degree per day. After 150 days, at the beginning of June 2004, the South pole region was reached with the pericentre already behind the terminator. Following, the pericentre moves northward with the Sun ^ation increasing. Thus, the optical instruments covered the Northern Mars hemisphere under good illumination conditions from mid-September 2004 to March 2005. During the next mission phase, lasting until July 2005, the pericentre was again in the dark. It covered the North polar region and moves southward. Finally, throughout the last 4 months of the nominal mission, the pericentre was back to daylight and moves from the equator to the South pole, and the downlink rate reached its highest rate of 228 kbit/s. The osculating orbit elements for the eq100 orbit are listed below: Epoch 2004:1:13 - 15:56:0.096 Pericentre (rel. sphere of 3397.2 km) 279.29 km Apocentre (rel. sphere) 11634.48 km Semimajor axis 9354.09 km Eccentricity 0.60696 Inclination 86.583 Right ascension of ascending node 228.774 Argument of pericentre 357.981 True anomaly -0.001 Mission Phases ============== The mission phases are defined as: (i) Pre-launch, Launch and Early Operations activities, including (1) science observation planning; (2) payload assembly, integration and testing; (3) payload data processing software design, development and testing; (4) payload calibration; (5) data archive definition and planning; (6) launch campaign. (ii) Near-Earth verification (EV) phase, including (1) commissioning of the orbiter spacecraft; (2) verification of the payload status; (3) early commissioning of payload. (iii) Interplanetary cruise (IC) phase (1) payload checkouts (2) trajectory corrections (iv) Mars arrival and orbit insertion (MOI) (1) Mars arrival preparation; (2) lander ejection; (3) orbit insertion; (4) operational orbit reached and declared; (5) no payload activities. (v) Mars commissioning phase (1) final instrument commissioning, (2) first science results, (3) change of orbital plane. (vi) Routine phase; Opportunities for dawn/dusk observations, mostly spectroscopy and photometry. This phase continued into a low data rate phase (night time; favorable for radar and spectrometers). Then daylight time, and went into a higher data rate period (medium illumination, zenith, then decreasing illumination conditions). Observational conditions were most favorable for the optical imaging instruments at the end of the routine phase, when both data downlink rate and Sun ^ation are high. (vii) MARSIS Deployment The dates of the MARSIS antenna deployment is not known as of writing this catalogue file. (viii) Extended operations phase A mission extension will be proposed in early 2005 to the Science Programme Committee (SPC). (ix) Post-mission phase (final data archival). Science Subphases ================= For the purpose of structuring further the payload operations planning, the mission phases are further divided into science subphases. The science subphases are defined according to operational restrictions, the main operational restrictions being the downlink rate and the Sun ^ation. The Mars Commissioning Phase and the Mars Routine Phase are therefore divided into a number of science subphases using various combinations of Sun ^ations and available downlink bit rates. The discrete downlink rates available throughout the nominal mission are: - 28 kbits/seconds - 38 kbits/seconds - 45 kbits/seconds - 57 kbits/seconds - 76 kbits/seconds - 91 kbits/seconds - 114 kbits/seconds - 152 kbits/seconds - 182 kbits/seconds - 228 kbits/seconds The adopted Sun ^ation coding convention is as follows: - HSE for High Sun Elevation (> 60 degrees) - MSE for Medium Sun Elevation (between 20 and 60 degrees) - LSE for Low Sun Elevation (between -15 and 20 degrees) - NSE for Negative Sun Elevation (< -15 degrees) The science subphase naming convention is as follows: - Science Phase - Sun Elevation Code - Downlink Rate - Science Subphase Repetition Number The following tables gives the available Science Subphases: NAME START END ORBITS BIT SUN RATE ELE ---------------------------------------------------------MC Phase 0 2003-12-30 - 2004-01-13 1 - 16 MC Phase 1 2004-01-13 - 2004-01-28 17 - 58 114 59 MC Phase 2 2004-01-28 - 2004-02-12 59 - 105 91 69 MC Phase 3 2004-02-12 - 2004-03-15 106 - 208 76 71 MC Phase 4 2004-03-15 - 2004-04-06 209 - 278 57 51 MC Phase 5 2004-04-06 - 2004-04-20 279 - 320 45 33 MC Phase 6 2004-04-20 - 2004-06-04 321 - 475 38 22 MR Phase 1 2004-06-05 - 2004-08-16 476 - 733 28 -13 MR Phase 2 2004-08-16 - 2004-10-16 734 - 951 28 -26 MR Phase 3 2004-10-16 - 2005-01-07 952 - 1250 28 16 MR Phase 4 2004-01-08 - 2005-03-05 1251 - 1454 45 63 MR Phase 5 2004-03-05 - 2005-03-24 1455 - 1522 76 16 MR Phase 6 2004-03-25 - 2005-07-15 1523 - 1915 91 0 The data rate is given in kbit per seconds and represents the minimal data rate during the subphase. The sun ^ation is given in degrees and represents the rate at the beginning of the subphase. Detailed information on the science subphases can be found in MEX-EST-PL-13128.
