Space Research Institute Dep. for experimental space research Austrian Academy of Sciences Graz - Austria VENUS EXPRESS MAGNETOMETER To Planetary Science Archive Interface Control Document VE-MAG-EAICD Version 1.4 18 November 2009 Prepared by: Magda Delva. W.Zambelli, Ch. Dunford Approved by: Tielong Zhang, PI Distribution List Recipient Organisation Recipient Change Log Date Sections Changed Reasons for Change 14. Dec. 2006 all First issue 18. Oct. 2007 3.1.1 Deliveries and Archive Volume Format Directory SOFTWARE added May 2008 All According to VE-EST-RID-MAG from first peer review, 2008-03 23 Sept. 2008 § 2.2.4 Operation and Data Sampling § 2.5.3 In-Flight Data Products § 3.1 Format and Conventions § 4.2 Data Sets, Definition and Content CODMAC2 in nT; higher data-rates added 20. Jan 2009 §2.5.3.2 §4.2.3 Data contents § Appendix I Description of RAW data modified 18. Nov. 2009 §2.5.3.2 Measurement data §3.2.3 Reference Systems §4.3.1 Data resolution for inflight products §4.3.2 Data contents Appendix II and III TBD ITEMS Section Description Table Of Contents 1 Introduction 3 1.1 Purpose and Scope 3 1.2 Archiving Authorities 3 1.2.1 ESA's Planetary Science Archive (PSA) 3 1.3 Contents 3 1.4 Intended Readership 3 1.5 Scientific Objectives 3 1.6 Applicable Documents 4 1.7 Relationships to Other Interfaces 4 1.8 Acronyms and Abbreviations 4 1.9 Contact Names and Addresses 4 2 Overview of Instrument Design, Data Handling Process and Product Generation 6 2.1 Science Background 6 2.2 Instrument Design 6 2.2.1 Introduction 6 2.2.2 Fluxgate Sensors 7 2.2.3 Sensor Position and Orientation 8 2.2.4 Operation and Data Sampling 8 2.2.5 Data filtering onboard 9 2.3 Data Handling Process 14 2.3.1 Overview 14 2.3.2 RAW data correction for sensor & filtering effects, synchronisation 14 2.3.3 RAW to CALIBRATED: correction for spacecraft stray field effects 14 2.4 Product Generation 15 2.5 Overview of Data Products 15 2.5.1 Pre-Flight Data Products 15 2.5.2 Instrument Calibrations 15 2.5.3 In-Flight Data Products 15 2.5.4 Software 16 2.5.5 Ancillary Data Usage 16 3 Archive Format and Content 17 3.1 Format and Conventions 17 3.1.1 Deliveries and Archive Volume Format 17 3.1.2 Data Set ID Formation 17 3.1.3 Data Directory Naming Convention 18 3.1.4 File-naming Convention 18 3.2 Standards Used in Data Product Generation 20 3.2.1 PDS Standards 20 3.2.2 Time Standards 20 3.2.3 Reference Systems 20 3.2.4 Other Applicable Standards 20 3.3 Data Validation 20 3.4 Content 20 3.4.1 Volume Set 20 3.4.2 Data Set 21 3.4.3 Directories 21 4 Detailed Interface Specifications 23 4.1 Structure and Organization Overview 23 4.2 Data Sets, Definition and Content 24 4.2.1 Data resolution for in-flight products 24 4.2.2 Data coverage 25 4.2.3 Data contents 25 4.3 Data Product Design 26 4.3.1 Data Product Design RAW_SENSOR_DATA 26 4.3.2 Data Product Design CALIBRATED_DATA 26 4.3.3 Data Product Design RESAMPED_CALIBRATED_DATA 26 APPENDIX I: Product Design RAW_SENSOR_DATA 27 APPENDIX II: Product Design CALIBRATED_DATA 37 APPENDIX III: Product Design RESAMPLED_CALIBRATED_DATA 45 1 Introduction 1.1 Purpose and Scope The purpose of this EAICD (Experimenter to (Science) Archive Interface Control Document) is two fold. First it provides users of the MAG magnetometer instrument with detailed description of the product and a description of how it was generated, including data sources and destinations. Secondly, it is the official interface between MAG magnetometer and ESA?s Planetary Science Archive. 1.2 Archiving Authorities The Planetary Data System Standard is used as archiving standard by * NASA for U.S. planetary missions, implemented by PDS * ESA for European planetary missions, implemented by the Research and Scientific Support Department (RSSD) of ESA 1.2.1 ESA's Planetary Science Archive (PSA) ESA implements an online science archive, the PSA, * to support and ease data ingestion * to offer additional services to the scientific user community and science operations teams as e.g. o search queries that allow searches across instruments, missions and scientific disciplines o several data delivery options as * direct download of data products, linked files and data sets * ftp download of data products, linked files and data sets The PSA aims for online ingestion of logical archive volumes and will offer the creation of physical archive volumes on request. 1.3 Contents This document describes the data flow of the MAG instrument on the Venus Express mission from the S/C until the insertion into the PSA for ESA. It includes information on how data were processed, formatted, labeled and uniquely identified. The document discusses general naming schemes for data volumes, data sets, data and label files. Standards used to generate the product are explained. Software that may be used to access the product is explained further on. The design of the data set structure and the data product is given. Examples of these are given in the appendix. 1.4 Intended Readership The staff of the archiving authority (Planetary Science Archive, ESA, RSSD, design team) and any potential user of the MAG magnetometer data. 1.5 Scientific Objectives The magnetometer aboard Venus Express (MAG) will conduct the following studies: * Provide the magnetic field data for any combined field, particle and wave studies such as lightning and planetary ion pickup processes; * Map with high time resolution the magnetic properties in the magnetosheath, magnetic barrier, the ionosphere, and the magnetotail. Identify the plasma boundaries between the various plasma regions. * Study of the solar wind interaction with the Venus atmosphere 1.6 Applicable Documents General PDS documents Planetary Data System Preparation Workbook, February 1, 1995, Version 3.1, JPL, D-7669, Part1 Planetary Data System Standards Reference, June 1, 1999, Version 3.3, JPL, D-7669, Part 2 Specific Venus Express and MAG instrument documents Document description Document reference Venus Express Archive Generation, VEX-RSSD-PL-001 Validation and Transfer Plan, in the current version VEX MAG instrument description ZHANGAL-MAG-ESA-SP1295 VEX MAG science data processing VE-MAG-SCIENCE-DATA- description, in the current version PROCESSING-DESCRIPTION (IWF) 1.7 Relationships to Other Interfaces None 1.8 Acronyms and Abbreviations PSA Planetary Science Archive MAG Venus Express magnetometer VEX Venus Express IWF Space Research Institute, Graz, Austria IC Imperial College, London, UK IGeP Institut fuer Geophysik und extraterrestrische Physik, TU Braunschweig, BRD EAICD Experimenter to (Science) Archive Interface Control Document ESA European Space Agency RSSD Research and Scientific Support Department of ESA S/C Spacecraft ASCII American Standard Code for Information Interchange UTC Coordinated Universal Time B Magnetic Field IS Inboard Sensor OS Outboard Sensor QF Quality Flag SW Software 1.9 Contact Names and Addresses PI: Dr. Tielong Zhang tielong.zhang@oeaw.ac.at +43 316 4120 - 552 Space Research Institute, Austrian Academy of Sciences Schmiedlstrasse 6, A 8042 Graz, Austria Archive responsibles: Dr. Magda Delva magda.delva@oeaw.ac.at +43 316 4120 - 553 Space Research Institute, Austrian Academy of Sciences Schmiedlstrasse 6, A 8042 Graz, Austria DI. Werner Zambelli werner.zambelli@oeaw.ac.at +43 316 4120 - 528 Space Research Institute, Austrian Academy of Sciences Schmiedlstrasse 6, A 8042 Graz, Austria Mr. Chris Carr c.m.carr@imperial.ac.uk Imperial College London Space & Atmospheric Physics Group The Blackett Laboratory London SW7 2BW, UK Ms. Charlotte Dunford c.dunford@imperial.ac.uk Imperial College London Space & Atmospheric Physics Group The Blackett Laboratory London SW7 2BW, UK 2 Overview of Instrument Design, Data Handling Process and Product Generation 2.1 Science Background Venus, like other planets in the solar system, is under the influence of a continuous flow of charged particles from the Sun, the solar wind. Lacking an intrinsic magnetic field makes Venus a unique object for studying the interaction between the solar wind and the planetary body. The planetary body has a dense atmosphere, but no magnetic field, thus the solar wind interacts directly with the upper atmosphere. The highly electrically conductive ionosphere deflects the oncoming supersonic solar wind around the planet so that a bow shock is formed. The interaction of post-shock solar wind flow and the ionosphere also results in a distinct boundary, the so-called ionopause. This ionopause separates the thermal plasma of the ionosphere from the hot magnetized plasma of the magnetosheath which is defined as the region between the ionopause and the bow shock. The absence of a planetary magnetic field leads to important differences between Venus' and Earth's atmospheric escape and energy deposition processes. The upper atmosphere of Venus is not protected by the magnetic field from direct interaction with the solar wind. As a result, a large portion of the exosphere resides in the shocked solar wind flow; the photo ionisation, charge exchange and electron impact ionisation effectively remove ionised exospheric components by the plasma flow. The tailward convection of the plasma mantle, situated between the shocked solar wind flow and the ionosphere, leads to another type of atmospheric loss. The ions gyrating around the magnetic field embedded in plasma may re-enter the atmosphere causing its massive sputtering. Finally, erosion of the Venusian ionosphere under varying solar wind conditions provides an additional loss mechanism for atmospheric constituents. The solar wind interacts with the top of the ionosphere to form a complex array of plasma clouds, tail rails, filaments and ionospheric holes on the night side through those a substantial amount of material leaves the planet. Figure 1 illustrates associated electrodynamics processes and plasma domains of the Venus upper ionosphere. The earlier missions, Venera and Pioneer orbiters found that the current induced by the solar wind electric field forms a magnetic barrier that deflects the most of the solar wind flow around the planet and leads to the formation of the bow shock. The ionosphere is terminated on the dayside, developing rapid anti-sunward convection and tail rays. However, the short lifetime of the Venera-9 and -10 orbiters, and insufficient temporal resolution of the Pioneer plasma instrument did not allowed a study of the mass exchange between the solar wind and the upper atmosphere of Venus and energy deposition to the upper atmosphere in sufficient detail. 2.2 Instrument Design 2.2.1 Introduction A short description of the instrument can be found in MAG: The Fluxgate Magnetometer of Venus Express Zhang, T.L. et al., 2005, ESA ? SP1295. (see DOCUMENT file: ZHANGAL-MAG-ESA-SP1295) The VEX magnetometer MAG measures the 3D magnetic field in the frequency bandwidth from DC to 128 Hz. It consists of two triaxial fluxgate sensors (MAGOS and MAGIS). The dual sensor configuration was chosen for a better monitoring of the stray magnetic fields produced from other S/C units. The electronics box comprises two sensor electronics boards, the DPU board and the DC/DC converter. MAGOS is mounted to the tip of a deployable boom whereas the inboard sensor (MAGIS) is directly attached to the +Z panel of the spacecraft. Sub-unit identification as well as a basic overview of the MAG functional blocks is given in the following figure. Fig. 2.2.1 Instrument hardware building blocks 2.2.2 Fluxgate Sensors Both fluxgate sensors, featuring low mass and power consumption, consist of two single ring-core sensors measuring the magnetic field in X- and Y-direction. The magnetic field in Z-direction is measured by a coil surrounding both single sensors. The side length of the cubic shaped sensor triad is approx. 5 cm. The sensor is identical to the ones of Rosetta Lander and MIR instrument package and similar to the ones flown on Equator-S (same soft-magnetic ringcores made of an ultra-stable 6-81 Mo permalloy band: 2 mm x 20 um). The ringcores have been tested under extreme environmental conditions aboard numerous space missions as well as in applied geophysics. The excellent low noise and stability behaviour of the sensor material has especially been proven aboard Equator-S. Because of the wide operating temperature range of the fluxgate sensor from -160C up to +120C, the sensor can be mounted outside of the temperature controlled S/C only covered by a passive multi-layer insulation blanket. No active heating or cooling is needed for the sensors. The instrument performed very well during ground calibration. At 1 Hz the noise density is less than 10 pT/(Hz for a sensor temperature range from 0C to +90C (the range in orbit around Venus) and the offset stability is better than 2 nT over the sensor temperature range from -75C to 90C. 2.2.3 Sensor Position and Orientation The following tables show the magnetic centers of the MAG sensors - deployed situation - with respect to the S/C coordinate system. Unit Xs Ys Zs [mm] [mm] [mm] MAGIS 247 -709 1683 MAGOS 377 -510 2622 Delta: 130 199 939 OS minus IS Tab. 2-1 Magnetic centers of MAGIS/OS in S/C coordinate system (deployed) Fig. 2.2-2 Instrument axes and orientation w.r.t spacecraft axes 2.2.4 Operation and Data Sampling MAG is based on the dual-magnetometer method to allow separation of the spacecraft stray field from the ambient space field. Therefore, both sensors always take measurements simultaneously. 2.2.4.1 The possible science modes are: Instrument Mode Sensors active Data Rate transmitted to Earth Solar wind OS and IS 1 Hz Pericenter OS and IS 32 Hz Burst OS and IS 128 Hz When MAG is active, data sampling onboard is always with 128 Hz data rate. For operation of the instrument in "Solar wind mode" and "Pericenter mode", the data samples are reduced by filtering methods to the required lower data rate by the onboard processor. Only for "Burst mode" the full set of data samples at 128 Hz data rate is transmitted to Earth. After switching on, MAG automatically operates in the standard mode which is "Solar wind mode" with simultaneous 1 Hz data of both sensors transmitted to Earth. 2.2.4.2 CRUISE phase: MAG was the first instrument to be commissioned on Venus Express, 10 days after launch, and its boom deployed. Afterwards, it remained ON during the commissioning of all the other instruments, to enable registration and characterisation of the magnetic disturbances generated during payload operation. During the CRUISE phase, only "Solar wind mode" is default and 1 Hz data rate is transmitted. Instrument Sensors active Data Rate Nominal operation Mode in cruise phase Solar wind OS and IS 1 Hz always active 2.2.4.3 Nominal science modes in nominal orbit around Venus (= after start of "nominal mission" 14-05-2006): MAG is operating continuously in orbit around Venus (which is in principle 24 hr per 24 hr orbit around Venus) and mostly in an autonomous mode, requiring little or no commanding. Higher data- rates are started only after start of the nominal mission in orbit around Venus (14 May 2006). During a typical science orbit, MAG is switched to "Pericenter mode" one hour before pericenter, and then back to "Solar wind mode" one hour after pericenter. The instrument is commanded to the high resolution "Burst mode" one minute before pericenter for duration of 2 min in order to detect lightning. Instrument Sensors active Data Rate Nominal operation Mode in cruise phase Solar wind OS and IS 1 Hz always active i.e. full orbit sampling coverage, except if mode with higher data rate is active Pericenter OS and IS 32 Hz 1 hr before and after pericenter Burst OS and IS 128 Hz 1 min before and after pericenter 2.2.5 Data filtering onboard Within the VEX-MAG software packet three different filter modes are implemented: * No Filter (FilterID = 0) * Averaging Filter (FilterID = 1) * FIR Filter (FilterID = 2) Using the telecommands MAGOSSetFilter and MAGISSetFilter the Filter option for each sensor can be selected. 2.2.5.1 No Filter This filter mode shall only be used when the raw data, sampled with 128 Hz is requested. In all other cases the Nyquist?Shannon sampling theorem is not satisfy and aliasing will be produced. If the data rate is set to 64Hz, each odd sample is transmitted while the even samples are dropped. In the case of 32Hz data rate each 4th sample is transmitted (1st, 5 th, 9 th...) while the other ones are dropped. 2.2.5.2 Averaging Filter Using this filter mode the 128 Hz raw data from the sensor electronics are averaged with an overlapping box car (averaging) filter. The frequency response for different data rates are shown in Fig. 2.2-3, Fig. 2.2-4 and Fig. 2.2-5. Fig. 2.2-3 Frequency response of the box car filter (data rate 64 Hz) Fig. 2.2-4: Frequency response of the box car filter (data rate 32 Hz) Fig. 2.2-5: Frequency response of the box car filter (data rate 2 Hz) 2.2.5.3 FIR Filter Using this filter mode the 128 Hz raw data from the sensor electronics are averaged with a cascade of FIR half band filter 17th order with Hanning characteristic. The Fig. 2.2-6 below shows the structure of the used FIR half band filter: Fig. 2.2-6: FIR half band filter 17th order The coefficients of this half band filter are given in the Table 2.2-1 : Coefficient Value a0 0 a1 -0.00531893983961 a2 0 a3 0.02629639672517 a4 0 a5 -0.07956381221274 a6 0 a7 0.30864305659745 a8 0.49988659745946 a9 0.30864305659745 a10 0 a11 -0.07956381221274 a12 0 a13 0.02629639672517 a14 0 a15 -0.00531893983961 a16 0 Table 2.2-1: Coefficients of the used 17th order FIR half band filter The complete filter bank is composed of a cascade of seven stages of the previous described FIR half band filter to achieve the decimation from 128Hz input data to 1Hz output data. The frequency response for different data rates are shown in Fig. 2.2-8 and Fig. 2.2-9. Fig: 2.2-7 Cascade of seven FIR half band filters Fig. 2.2-8: Frequency response of the FIR filter (data rate 64 Hz) Fig. 2.2-9: Frequency response of the FIR filter (data rate 32 Hz) 2.2.5.4 Applied filter to the in-flight 1Hz data For the 1 Hz data in-flight (and later also on ground) only the FIR filter was used. 2.3 Data Handling Process 2.3.1 Overview Data processing is executed in several steps and with various methods. Processing of the data received from the spacecraft to obtain RAW data: * Correction of spacecraft received data for known sensor effects * Synchronisation of the two sensor data-sets From RAW to CALIBRATED data: * Raw-data correction for variable S/C stray field effects (neural networks, fuzzy logics, model fitting) * Raw-data correction for secular S/C stray field effects (Solar Wind methods) * The calibration procedure on the measurements of the two sensors yields the space magnetic field vector as result, in spacecraft coordinates From CALIBRATED to RESAMPLED data: Here mainly averaging methods are used. 2.3.2 Data correction for sensor & filtering effects, synchronisation to get RAW data (CODMAC level 2) This part of the data-correction is an INTERNAL pipeline done at IWF-Graz and described in the IWF-INTERNAL document in the current version: VE-MAG-SCIENCE-DATA-PROCESSING-DESCRIPTION 2.3.3 RAW to CALIBRATED: correction for spacecraft stray field effects The measurements during flight are the sum of the ambient space field and stray fields from the spacecraft, with the space field the same at both sensors. When the magnetometers are well-calibrated, i.e. they perform identically, then any difference is attributable to the spacecraft. If a single source is identified at a known position on the spacecraft, a model dipole field can be determined from the dual magnetometer measurement and subtracted to obtain the ambient space field. From this initial state, any change in the spacecraft effects is indicated by a change in the difference between the measurements at both sensors. In principle, identification of the disturbing source (and its temporal changes) from the in-flight telemetry enables a correction of the data for the stray field effects. Optimally, the corresponding model dipoles known from the ground survey can be used. However, the Venus Express stray field effects are much more complicated and of a multi-dipole nature, so a combination of different methods is used. In the solar wind, well-known statistical methods, using time series of solar wind measurements, are used to determine an initial ambient space field level from the measurements at both sensors, with the data-difference only due to some initial state of the spacecraft effects. Temporal variations from this initial state are detected and, if possible, allotted to a single source on the spacecraft to allow correction. For Venus Express, routine manual identification of stray field patterns and their sources (known from the magnetic survey) and subsequent correction are beyond the resources of the MAG team. This raises the need for an automated correction procedure. Since 2003, a new method of combining dual magnetometry and high performance computation using neural networks has been under consideration. A neural network pattern-recognition algorithm was developed to identify stray field patterns in the differences of the magnetic field measurements at the sensors. A test algorithm was applied to simulated measurement data (ambient field and disturbance from up to seven simultaneous model dipoles), producing satisfactory results. The algorithm was successfully tested on real magnetic field measurements from Double Star. MAG data from the commissioning of the other instruments and the cruise data provided a "learning sequence" for the neural network algorithm. For the science data at Venus, a combination of the automated neural network algorithm and, in the worst case, correction by human resources is being applied. 2.4 Product Generation The available data-sets at IWF are transformed by the IWF archiving team to the required PDS structure. 2.5 Overview of Data Products 2.5.1 Pre-Flight Data Products NO pre-flight products are included in the archive. 2.5.2 Instrument Calibrations NO calibration functions are included in the archive. information about the calibration and details is stored at IWF. 2.5.3 In-Flight Data Products In-flight data products are restricted to the measured data only. 2.5.3.1 Housekeeping data (HK) NO HK data (temperatures, voltages) are injected into the archive, since they are NOT used for calibration. They are stored at IWF and are used for monitoring the health of the instrument. Since this is in perfect order, NO HK data were used for calibration. 2.5.3.2 Measurement data The following types of data are in the archive: RAW_SENSOR DATA = data in nano Tesla, CODMAC level 2 : Raw, synchronized sensor data Data from the two sensors MAG-IS, MAG-OS in S/C coordinates, synchronized, in nano Tesla [nT]. Data are corrected for known sensor-effects; at certain times the data from both sensors still consist of a significant amount of variable spacecraft background field; the ratio of the background spacecraft field at the sensors is variable in time. Data of this type are available for different data resolutions: 1 Hz, 32 Hz, 128 Hz. WARNING: Due to the variability of the spacecraft field in the RAW sensor data, these data should be used with caution and in collaboration with the MAG-team. CALIBRATED DATA = Space magnetic field data, in physical units, CODMAC level 3: Space magnetic field data in physically meaningful coordinates (HSE;VSO) in nanoTesla; position of S/C in meaningful coordinate system. Data of this type are available for data resolution of 1 Hz. RESAMPLED CALIBRATED DATA = Averaged space magnetic field data, in physical units, CODMAC level 4: Space magnetic field data in physically meaningful coordinates (HSE, VSO) in nanoTesla; averaged from space magnetic field data; position of S/C in meaningful coordinate system. Data of this type are available with data resolution lower than 1Hz Definition of the coordinate systems is given in chapter 3.2.3 Reference Systems. IMPORTANT NOTES: * In-flight data products are restricted to "Solar wind mode" (=1 Hz) data only. All data intervals of higher data rate are down-sampled with the same methods as onboard (see chapter 2.2.4 ) and merged into the 1 Hz data set, to enable a full coverage with equidistant samples in time. * So 1 Hz data are available for the whole mission duration (after Venus orbit insertion, 12 April 2006) and nearly without data-gaps, since MAG is ON in principle at ALL times. * CODMAC LEVEL 2 data, i.e. RAW SENSOR DATA, are available in the archive on a regular basis for the 1 Hz, 32 Hz, 128 Hz data. * CODMAC 3 and CODMAC 4 data-levels are processed from the 1 Hz raw data and therefore include the downsampled and calibrated higher data rates. A single calibration of the higher data rate 32Hz is only possible on request for specific users and for specific dates. 2.5.4 Software The data processing software is available at IWF-Graz, but NOT available in the archive, since there is no single straight-forward pipeline; data are run through several single packages by various groups. These data-processing steps cannot be performed in a straight forward way and, therefore, no software is delivered. 2.5.5 Ancillary Data Usage MAG uses orbit, attitude, orbit number data from ESOC within the data processing chain, to produce data in a physically meaningful coordinate system. 3 Archive Format and Content 3.1 Format and Conventions 3.1.1 Deliveries and Archive Volume Format Each MAG archive data-set has the following structure, where one volume is one data-set, i.e. volume and data-set are identical. DATASET_ID |--- CATALOG |--- DATA |--- DOCUMENT |--- INDEX 3.1.2 Data Set ID Formation The maximum length of the DATA_SET_ID is 40 characters. Multiple targets will be referenced by concatenation of the values with a "/", which is interpreted as "and" and is formatted like this: DATA_SET_ID = " - - - - " For example: 123456789012345678901234567 VEX-V/Y-MAG-2-V1.0 where: Element Value Status VEX req V/Y req MAG req CODMAC level 2,3,4 req e.g. V1.0 req Table 1 Elements for the DATA_SET_ID formation. TARGET_NAME TARGET_TYPE in in DATA_SET_NAME DATA_SET_ID "VENUS" "PLANET" VENUS V "EARTH" "PLANET" EARTH E "MARS" "PLANET" MARS M "CALIBRATION" "CALIBRATION" CAL CAL "CHECKOUT" "N/A" CHECK X "SOLAR WIND" "SOLAR SYSTEM" SW Y Table 2 Standard values related to targets. 3.1.3 Data Directory Naming Convention In the DATA-directory, data are archived according to different phases from the flight before the Venus Orbit Insertion. After Venus orbit injection, data directories are archived according to DATA PHASE NAME, which is according to DATE and not according to orbit numbers. Therefore, all DATA-directory-names contain a " DATA PHASE NAME", as defined in Table 3, and an indication of the data- or time-resolution of the data. No directory name is longer than 32 characters and the data directory has the following structure: |--- DATA |--- XXXXXXXXX_ZZZZ Filename1 per DOY Filename2 per DOY Etc. |--- XXXXXXXXX_ZZZZ where: XXXXXXXXX : data phase name ID ZZZZ : denotes the data-rate or resolution of the data in the files. DZZZ : denotes the DATA-rate of the data in the file for the products RAW_SENSOR_DATA CALIBRATED_DATA values are according to the sheme: D001 for 1 Hz data-rate [D032 for 32 Hz data-rate (NOT in the archive)] [D128 for 128 Hz data-rate (NOT in the archive)] RZZZ : denotes the DATA-rate in the file for the product RESAMPLED_CALIBRATED_DATA values are according to the sheme: SZZZ (Resolution in ZZZ Seconds) MZZZ (Resolution in ZZZ Minutes) HZZZ (Resolution in ZZZ Hours) DATA_PHASE_NAME DATA_PHASE_NAME_ID in DATA-Directory-names "XXXXXXXXX" "Commissioning at Earth" "COMMEARTH" ?Cruise Phase year month? "CRU200601" "CRU200602" "CRU200603" ?Capture Orbit at Venus? "CAPTORBIT" ?Commissioning at Venus? "COMMVENUS" ?Orbit at Venus year month? "ORB200605" "ORB200606" Etc ... Table 3 Data Phase name descriptions 3.1.4 File-naming Convention This is the MAG file-naming convention for the data-files in the DATA-sub-directories. File-names are NOT longer than 31 digits, ie. name(<=27).ext(3) (PDS standard). All data are archived in ASCII-files. * Data Product RAW_SENSOR_DATA : = Raw synchronized sensor data, CODMAC Level 2: Position: 123456789012345678901234567.123 Filename: BIO_YYYYMMDD_DOYXXX_DZZZ_VN.TAB where YYYYMMDD : date XXX : day of the year DZZZ : denotes the DATA-rate of the data in the file, where D is used for original data-rate files from the S/C; values are according to the sheme: D001 for 1 Hz data-rate [D032 for 32 Hz data-rate (NOT in the archive)] [D128 for 128 Hz data-rate (NOT in the archive)] N : Version number Example: BIO_20061115_DOY319_D001_V1.TAB * Data Product CALIBRATED data: = Space magnetic field data, CODMAC Level 3: Position: 123456789012345678901234567.123 Filename: MAG_YYYYMMDD_DOYXXX_DZZZ_VN.TAB where YYYYMMDD : date XXX : day of the year DZZZ : denotes the DATA-rate of the data in the file, where D is used for original data-rate files from the S/C; values are according to the sheme: D001 for 1 Hz data-rate [D032 for 32 Hz data-rate (NOT in the archive)] [D128 for 128 Hz data-rate (NOT in the archive)] N : Version number Example: MAG_20061115_DOY319_D001_V1.TAB * Data Product RESAMPLED CALIBRATED DATA: = Resampled space magnetic field data, CODMAC Level 4: Position: 123456789012345678901234567.123 Filename: MAG_YYYYMMDD_DOYXXX_RZZZ_VN.TAB where YYYYMMDD : date XXX : day of the year RZZZ : denotes the DATA-rate of the data in the file, with possibilities: (same as defined above for the directory names) SZZZ (Resolution in ZZZ Seconds) MZZZ (Resolution in ZZZ Minutes) HZZZ (Resolution in ZZZ Hours) N : Version number Example: MAG_20061115_DOY319_S004_V1.TAB 3.2 Standards Used in Data Product Generation 3.2.1 PDS Standards MAG complies to PDS version 3, and uses version 3.6 of the PDS standard reference. 3.2.2 Time Standards Time (UTC) in files: CCJJ-MM-DDT-HH:MM:SS.sss 3.2.3 Reference Systems * Spacecraft coordinates (S/C coordinates): as defined by the spacecraft team; Used for all phases of the Venus Express mission for RAW SENSOR DATA CALIBRATED DATA * HSE : solar ecliptic coordinates, only applicable during the CRUISE phase (x,y)-plane is the ecliptic plane, x axis positive to the Vernal Equinox, z axis positive to Ecliptic North. Used for: RESAMPLED CALIBRATED DATA in CRUISE phase only. * VSO : Venus solar orbit coordinates (x,y) plane is the orbital plane of Venus; x-axis is pointing to the solar direction, i.e. on the line Venus-Sun and positive towards the Sun y-axis is perpendicular to the x-axis, but positive in direction of negative orbital velocity of Venus z-axis completes the right hand system (i.e. z-axis is parallel to the Venus orbital angular momentum vector) Used for RESAMPLED CALIBRATED DATA after Venus Orbit Insertion only. * Earth Equatorial. Coord. J2000 (x,y) plane is the Earth equatorial plane x-axis is pointing to the Equinox as defined for the Epoch J2000 z-axis points to Earth Nord pole. Used for the Keywords in /* ORBITAL INFORMATION*/ about the position of the spacecraft relative to Earth in all data-files. 3.2.4 Other Applicable Standards N/A 3.3 Data Validation Data are checked for self-consistency when decommutating to edited raw format. Raw synchronized data of MAGIS and MAGOS sensors are compared. They show similar structures, originated in the solar wind, and also spacecraft field effects, which have a smaller effect on the MAGOS sensor. Before archiving a data set from some mission phase, this set has been used and validated internally by MAG scientists and engineers. 3.4 Content 3.4.1 Volume Set According to the Planetary Data Sytem Standard Ferference, Version 3.6, Chapter 19, Figure 19.1, i.e. one data-volume is identical to one data-set. 3.4.2 Data Set The data set name will follow the following convention: DATA_SET_NAME = " " 3.4.3 Directories 3.4.3.1 Root Directory The root directory for the VEX-MAG data is named with the DATA_SET_ID. File Description Responsibility AAREADME.TXT Overview description of MAG Team contents of dataset ERRATA.TXT A text file containing MAG Team a cumulative listing of comments and updates concerning all MAG standard data products on all MAG volumes in the volume set published to date VOLDESC.CAT A description of the contents MAG Team of this volume in a PSA format readable by both humans and computers 3.4.3.2 Catalog Directory File Description Responsibility CATINFO.TXT A description of the MAG Team contents of this directory DATASET.CAT A description of the MAG MAG Team dataset in the actual mission phase INSTHOST.CAT A description of the Venus VSOC Express s/c acting as instrument host for all the experiments. INST.CAT A complete instrument MAG Team description of the magnetometer MAG. MISSION.CAT A description of the Venus VSOC Express mission to Venus. PERSON.CAT PSA personnel catalog MAG Team description of MAG team members and other persons involved with generation of MAG data products REF.CAT The file contains publication MAG Team references of all publications mentioned in the CATALOG files. 3.4.3.3 Index Directory File Description Responsibility INDEXINFO.TXT A description of the contents MAG Team of this directory INDEX.TAB A detailed list of contents MAG Team for the dataset as generated by the PSA's PVV software INDEX.LBL The PSA detached label for the MAG Team INDEX file 3.4.3.4 Document Directory File Description Responsibility DOCINFO.TXT A description of the MAG Team contents of this directory VE-MAG-EAICD.DOC The EAICD (this document), MAG Team in Microsoft Word format VE-MAG-EAICD.PDF The EAICD in Adobe's Portable MAG Team Documents Format format VE-MAG-EAICD.TXT The EAICD in ASCII format MAG Team VE-MAG-EAICD.LBL A PSA detached label for MAG Team the EAICD document ZHANGAL-MAG-ESA- MAG instrument description, MAG Team SP1295.DOC ESA SP 2005, in Microsoft Word format ZHANGAL-MAG-ESA- MAG instrument description, MAG Team SP1295.PDF ESA SP 2005, in Adobe's Portable Documents Format ZHANGAL-MAG-ESA- MAG instrument description, MAG Team SP1295.TXT ESA SP 2005, in ASCII format ZHANGAL-MAG-ESA-S A PSA detached label for the MAG Team P1295.LBL ESA SP 2005 document VE-MAG-SCIENCE- MAG science data processing MAG Team DATA-PROCESSING- description in Microsoft Word DESCRIPTION.DOC format VE-MAG-SCIENCE- MAG science data processing MAG Team DATA-PROCESSING- description in Adobe's Portable DESCRIPTION.PDF Documents format VE-MAG-SCIENCE- MAG science data processing MAG Team DATA-PROCESSING- description in ASCII forma DESCRIPTION.TXT VE-MAG-SCIENCE- A PSA detached label for the MAG Team DATA-PROCESSING- MAG science data processing DESCRIPTION.LBL description 3.4.3.5 Data Directory As described in chapter 3.1.3 4 Detailed Interface Specifications 4.1 Structure and Organization Overview Different data-volumes contain the data of the different parts of the mission: Nominal mission: from start 09 Nov. 2005 to 03 Oct 2007 VEX-V/Y-MAG-2-VZ VEX-V/Y-MAG-3-VZ VEX-V/Y-MAG-4-VZ First extension of mission: from 04 Oct 2007 to 31 May 2009 VEX-V/Y-MAG-2-EXT1-VZ VEX-V/Y-MAG-3-EXT1-VZ VEX-V/Y-MAG-4-EXT1-VZ Second extension of mission: from 01 June 2009 to end of mission VEX-V/Y-MAG-2-EXT2-VZ VEX-V/Y-MAG-3-EXT3-VZ VEX-V/Y-MAG-4-EXT4-VZ The structure of each data-volume is as follows, according to § 3.1.3: DATA_SET_ROOT |---VEX-V/Y-MAG-2-VZ.0 DATA-SET for CODMAC level 2 AAREADME.TXT VOLDESC.CAT |--- CATALOG |--- DATA |--- XXXXXXXXX_D001 Filename1 per DOY Filename2 per DOY Etc. |--- XXXXXXXXX_D001 |--- DOCUMENT |--- INDEX |--- VEX-V/Y-MAG-3-VZ.0 DATA-SET for CODMAC level 3 |---VEX-V/Y-MAG-4-VZ.0 DATA-SET for CODMAC level 4 4.2 Data Sets, Definition and Content 4.2.1 Data resolution for in-flight products As already mentioned in chapter 2.2.4 Operation and Data Sampling and chapter 2.5.3 In-Flight Data Products only in-flight data and measured data are available in the archive. NO HK data (temperatures, voltages) are injected into the archive, since they are NOT used for calibration. For the in-flight data products RAW SENSOR DATA CALIBRATED DATA only 1 Hz data (= Solar wind mode) are available in the archive, since all data intervals of higher data rate are down-sampled with the same methods as onboard and merged into the 1 Hz data-set, to enable a full coverage with equidistant samples in time. So 1 Hz data are available for the whole mission duration and nearly without data-gaps, since MAG is ON in principle at ALL times. The in-flight data products RESAMPLED CALIBRATED DATA principally can be available in various resampled data resolutions, but with sampling rate slower than 1 Hz; base line is 4 secs resolution or lower. 4.2.2 Data coverage For all Venus Express mission phases, data are available on a DAY to DAY basis, i.e. one file per calender day, except where the spacecraft was in save mode or other non-measuring state. For normal operation of the spacecraft in orbit, a full 24 hr coverage of the MAG data is offered. For normal operation of MAG, data-gaps can occurr within the archived daily files; these are due to switching effects of the sensors (from mode to mode), due to lack of good calibration, due to uncorrectable magnetic effects on the spacecraft itself. 4.2.3 Data contents One data-set is generated per CODMAC level of the data; CODMAC levels were described in chapter 2.5.3: CODMAC level 2 = RAW_SENSOR DATA = Raw, synchronized sensor data, data in nano Tesla (nT). This data type is available for different data resolutions: 1 Hz, 32 Hz, 128 Hz. WARNING: Due to the variability of the spacecraft field in the RAW sensor data, these data should be used with caution and in collaboration with the MAG-team. Data from the two sensors MAG-IS, MAG-OS in S/C coordinates, synchronized, in nano Tesla. Data are corrected for known sensor-effects, at certain times the data from both sensors still consist of a sifnificant amount of variable spacecraft background field; the ratio of the background spacecraft field at the sensors is variable in time. UTC, BISX; BISY, BISZ, BIST, BOSX, BOSY, BOSZ, BOST, (BIS-BOS)X, (BIS-BOS)Y, (BIS-BOS)Z, (BIS-BOS)T UTC: Time of observation, in universal time BISX, BISY, BISZ, BIST: Components of the field and the respective total value (in nT) at the inboard sensor MAG-IS, in S/C coordinates. BOSX, BOSY, BOSZ, BOST: Components of the field and the respective total value (in nT) at the outboard sensor MAG-OS, in S/C coordinates. (BIS-BOS)X, (BIS-BOS)Y, (BIS-BOS)Z, (BIS-BOS)T: Difference (inboard minus outboard) of the field and the total of the difference (in nT), in S/C coordinates. The difference is important as indicator for changes in the S/C magnetic state. Constant differences indicate a constant magnetic background field of the S/C; as long as the difference is constant, the calibration can be regarded as stable. Changes in the difference indicate that a change in calibration of the data is required, and this can cause problems. If any problem is detected in the calibrated data or higher data products, a check of the difference (BIS-BOS) on the respective RAW_SENSOR_DATA file can directly reveal if this is due to a calibration change or not. The contents is also described in Appendix I. CODMAC level 3 = CALIBRATED DATA = Space magnetic field data, in physical units This data type is available ONLY for data resolution 1 Hz Space magnetic field data in physically meaningful coordinates (HSE;VSO) in nanoTesla; position of S/C in meaningful coordinate system UTC, BX, BY, BZ, BT, XSC, YSC, ZSC, RSC UTC: Time of observation, in universal time BX, BY, BZ, BT: Components of the space magnetic field and the respective total in physically meaningful coordinates and in nanoTesla. XSC, YSC, ZSC, RSC: Position of the spacecraft in the same coordinate system, in km. There is NO straight forward relation between the RAW_SENSOR_DATA and CALIBRATED_DATA, but depends on calibration. If any problem is detected in the calibrated data or higher data products, a check of the difference (BIS-BOS) on the respective RAW_SENSOR_DATA file can directly reveal if this is due to a calibration change or not. The contents is also described in Appendix II. CODMAC level 3 will not be generated for the data-rates 32 Hz and 128 Hz, because the calibration of these data is not possible on a regular basis. CODMAC level 4 = RESAMPLED CALIBRATED DATA = Averaged space magnetic field data, in physical units. This data type is available ONLY for data resolution lower than 1 Hz, baseline is 4 secs resolution. Space magnetic field data in physically meaningful coordinates (HSE, VSO) in nT, averaged from space magnetic field data; position of S/C in meaningful coordinate system UTC, BX, BY, BZ, BT, XSC, YSC, ZSC, RSC UTC: Time of observation, in universal time BX, BY, BZ, BT: Averaged components of the space magnetic field and the respective total, in physically meaningful coordinates and in nanoTesla. XSC, YSC, ZSC, RSC: Position of the spacecraft in the same coordinate system, in km. If any problem is detected in the calibrated data or higher data products, a check of the difference (BIS-BOS) on the respective RAW_SENSOR_DATA file can directly reveal if this is due to a calibration change or not. The contents is also described in Appendix III 4.3 Data Product Design 4.3.1 Data Product Design RAW_SENSOR_DATA See Appendix I: DATAFILELABEL_CODMAC_2 4.3.2 Data Product Design CALIBRATED_DATA See Appendix II: DATAFILELABEL_CODMAC_3 4.3.3 Data Product Design RESAMPED_CALIBRATED_DATA See Appendix III: DATAFILELABEL_CODMAC_4 APPENDIX I: Product Design RAW_SENSOR_DATA Keyword SSE Type Description Example PDS_VERSION_ID SC ID PDS3 PDS3 LABEL_REVISION_NOTE SC CHAR Release and Revision information "V1.0" /* FILE RELATED INFORMATION*/ PRODUCT_ID SC CHAR Current file name, with extension (example: ) "BIO_20061115_DOY319_D001_V1.TAB" RECORD_TYPE SC ID FIXED_LENGTH FIXED_LENGTH RECORD_BYTES SC INT Record length in bytes, constant 160 FILE_RECORDS SC INT Total file length / RECORD_BYTES 86522 (closest integer greater than or equal to this value) (123 LBL-lines+ 86400 Data-lines) LABEL_RECORDS SC INT number of physical file records that contain "BIO_20061115_DOY319_D001_V1.LBL" only label information SOURCE_NAME SC CHAR Source file name "BIO_2005-11-20T00-00-32_DOY_324_D001_1_DIF.dat" /* DATA POINTER IDENTIFICATION */ ^TABLE SC PTR only if Data and Label are in the same file 19520 (start at first entry in first data line) /* PRODUCER IDENTIFICATION */ PRODUCER_ID SC ID VEX-MAG-TEAM "VEX_MAG_TEAM" PRODUCER_FULL_NAME SC CHAR DELVA-ZAMBELLI "DELVA MAGDA, ZAMBELLI WERNER" PRODUCER_INSTITUTION_NAME SC CHAR IWF-GRAZ "INSTITUT FUR WELTRAUMFORSCHUNG - GRAZ" PRODUCT_CREATION_TIME SC TIME 2007-10-18T13:47:13 /* DATA DESCRIPTION AND IDENTIFICATION */ DATA_SET_NAME SC CHAR Description of the DATA_SET_ID (in words) "VENUS-EXPRESS VENUS MAG 2 V1.0" DATA_SET_ID SC CHAR "VEX-V/Y-MAG-2-V1.0" RELEASE_ID SC INT V1.0 1 REVISION_ID SC INT V1.0 0 PRODUCT_TYPE SC CHAR DER (Experiment Data Record) "EDR" PROCESSING_LEVEL_ID SC INT CODMAC 2 2 MISSION NAME SC CHAR VENUS EXPRESS "VENUS EXPRESS" MISSION_ID SC ID VEX "VEX" INSTRUMENT_HOST_NAME SC ID VENUS EXPRESS "VENUS EXPRESS" INSTRUMENT_HOST_ID SC ID VEX "VEX" MISSION_PHASE_NAME SC CHAR VEX MISSION PHASE "PHASE1" (defined from VEX-OrbitNr List) INSTRUMENT_NAME SC CHAR MAG "MAGNETOMETER" INSTRUMENT_ID SC CHAR MAG "MAG" INSTRUMENT_TYPE SC CHAR MAGNETOMETER "MAGNETOMETER" ^INSTRUMENT_DESC SC CHAR Pointer to file: INST.CAT "^INST.CAT" /* TARGET IDENTIFICATION */ TARGET_TYPE SC CHAR PLANET "PLANET" TARGET_NAME SC CHAR VENUS "VENUS" /* TIME RELATED INFORMATION */ START_TIME SC SC TIME 2006-11-15T00:00:00.855 STOP_TIME SC TIME 2006-11-15T23:59:59.917 SPACECRAFT_CLOCK_START_COUNT SC CHAR S/C CLOCK TICS SPACECRAFT_CLOCK_STOP_COUNT SC CHAR S/C CLOCK TICS /* ORBITAL INFORMATION */ SC_SUN_POSITION_VECTOR REAL ( 141024080.54, -45879280.26, -19810607.77) SC_TARGET_POSITION_VECTOR REAL ( 1361441.35, -325381.79, -61141.68) SC_TARGET_VELOCITY_VECTOR REAL ( -3.85, 0.87, 0.14) NOTE "The values of the keywords SC_SUN_POSITION_VECTOR, SC_TARGET_POSITION_VECTOR, SC_TARGET_VELOCITY_VECTOR in Earth Eq. Coord. J2000 are valid for the time T= 00:00:00,. Distances are given in velocities in ." PERIAPSIS_TIME TIME 2006 APR 20 08:07:37 PERIAPSIS_ALTITUDE REAL ALTITUDE ABOVE VENUS NOMINAL SURFACE 256.28 SPACECRAFT_ALTITUDE REAL SPACECRAFT ALTITUDE 256.28 SUB_SPACECRAFT_LATITUDE REAL S/C LATITUDE IN PLANETOCENTRIC COORD. 295.22 SUB_SPACECRAFT_LONGITUDE REAL S/C LONGITUDE IN PLANETOCENTRIC COORD. 77.4 ORBIT_NUMBER SC INT ORBIT NR DEFINED BY VSOC 1 NOTE "The values of the keywords ORBIT_NUMBER, SUB_SPACECRAFT_LATITUDE, SUB_SPACECRAFT_LONGITUDE are given for PERIAPSIS_TIME; altitude is in , angles in degrees" /* QUALITY IDENTIFICATION */ DATA_QUALITY_ID SC INT N/A "N/A" DATA_QUALITY_DESC SC CHAR N/A "N/A" /* INSTRUMENT RELATED INFORMATION*/ INSTRUMENT_MODE_ID SC INT Solar wind 1 "SW1" ^INSTRUMENT_MODE_CATALOG SC CHAR Pointer to file INST.CAT "^INST.CAT" NOTE "Please note that some of the values in the TABLE object are given in different reference frames. Where this is the case, it is indicated in the DESCRIPTION keyword of the relevant column" /* OBJECT DEFINITION */ OBJECT TABLE TABLE NAME CHAR MAG RAW_SENSOR_DATA INTERCHANGE_FORMAT CHAR ASCII ROWS INT 86400 COLUMNS INT 13 ROW_BYTES INT 160 OBJECT COLUMN COLUMN NAME "TIME_UTC" COLUMN_NUMBER 1 DATA_TYPE TIME START_BYTE 1 BYTES 23 DESCRIPTION "UTC TIME OF OBSERVATION:" "YYYY-MM-DDTHH:MM:SS.FFF" END OBJECT COLUMN OBJECT COLUMN COLUMN NAME "BISX" COLUMN_NUMBER 2 DATA_TYPE ASCII_INTEGER START_BYTE 25 BYTES 10 UNIT "N/A" DESCRIPTION Please note that this value is given in the spacecraft reference frame. Data from MAG inboard sensor at 1Hz, X COMPONENT, in nano Tesla; at certain times a significant amount of variable spacecraft background field is contained in the data. DATA_FLAG_VALUE = 99999.999 END OBJECT COLUMN OBJECT COLUMN COLUMN NAME "BISY" COLUMN_NUMBER 3 DATA_TYPE ASCII_INTEGER START_BYTE 36 BYTES 10 UNIT "N/A" DESCRIPTION Please note that this value is given in the spacecraft reference frame. Data from MAG inboard sensor at 1Hz, Y COMPONENT, in nano Tesla; at certain times a significant amount of variable spacecraft background field is contained in the data. DATA_FLAG_VALUE = 99999.999 END OBJECT COLUMN OBJECT COLUMN COLUMN NAME "BISZ" COLUMN_NUMBER 4 DATA_TYPE ASCII_INTEGER START_BYTE 47 BYTES 10 UNIT "N/A" DESCRIPTION Please note that this value is given in the spacecraft reference frame. Data from MAG inboard sensor at 1Hz, Z COMPONENT, in nano Tesla; at certain times a significant amount of variable spacecraft background field is contained in the data. DATA_FLAG_VALUE = 99999.999 END OBJECT COLUMN OBJECT COLUMN COLUMN NAME "BIST" COLUMN_NUMBER 5 DATA_TYPE ASCII_INTEGER START_BYTE 58 BYTES 10 UNIT "N/A" DESCRIPTION Please note that this value is given in the spacecraft reference frame. Data from MAG inboard sensor at 1Hz, TOTAL, in nano Tesla; at certain times a significant amount of variable spacecraft background field is contained in the data. DATA_FLAG_VALUE = 99999.999 END OBJECT COLUMN OBJECT COLUMN COLUMN NAME "BOSX" COLUMN_NUMBER 6 DATA_TYPE ASCII_INTEGER START_BYTE 69 BYTES 10 UNIT "N/A" DESCRIPTION Please note that this value is given in the spacecraft reference frame. Data from MAG outboard sensor at 1Hz, X COMPONENT, in nano Tesla; at certain times a significant amount of variable spacecraft background field is contained in the data. DATA_FLAG_VALUE = 99999.999 END OBJECT COLUMN OBJECT COLUMN COLUMN NAME "BOSY" COLUMN_NUMBER 7 DATA_TYPE ASCII_INTEGER START_BYTE 80 BYTES 10 UNIT "N/A" DESCRIPTION Please note that this value is given in the spacecraft reference frame. Data from MAG outboard sensor at 1Hz, Y COMPONENT, in nano Tesla; at certain times a significant amount of variable spacecraft background field is contained in the data. DATA_FLAG_VALUE = 99999.999 END OBJECT COLUMN OBJECT COLUMN COLUMN NAME "BOSZ" COLUMN_NUMBER 8 DATA_TYPE ASCII_INTEGER START_BYTE 91 BYTES 10 UNIT "N/A" DESCRIPTION Please note that this value is given in the spacecraft reference frame. Data from MAG outboard sensor at 1Hz, Z COMPONENT, in nano Tesla; at certain times a significant amount of variable spacecraft background field is contained in the data. DATA_FLAG_VALUE = 99999.999 END OBJECT COLUMN OBJECT COLUMN COLUMN NAME "BOST" COLUMN_NUMBER 9 DATA_TYPE ASCII_INTEGER START_BYTE 102 BYTES 10 UNIT "N/A" DESCRIPTION Please note that this value is given in the spacecraft reference frame. Data from MAG outboard sensor at 1Hz, TOTAL, in nano Tesla; at certain times a significant amount of variable spacecraft background field is contained in the data. DATA_FLAG_VALUE = 99999.999 END OBJECT COLUMN OBJECT COLUMN COLUMN NAME "(BIS-BOS)X" COLUMN_NUMBER 10 DATA_TYPE ASCII_INTEGER START_BYTE 113 BYTES 10 UNIT "N/A" DESCRIPTION Please note that this value is given in the spacecraft reference frame. Data from MAG inboard and outboard sensor at 1Hz, X COMPONENT, in nano Tesla; at certain times a significant amount of variable spacecraft background field is contained in the data. DATA_FLAG_VALUE = 99999.999 END OBJECT COLUMN OBJECT COLUMN COLUMN NAME "(BIS-BOS)Y" COLUMN_NUMBER 11 DATA_TYPE ASCII_INTEGER START_BYTE 124 BYTES 10 UNIT "N/A" DESCRIPTION Please note that this value is given in the spacecraft reference frame. Data from MAG inboard and outboard sensor at 1Hz, Y COMPONENT, in nano Tesla; at certain times a significant amount of variable spacecraft background field is contained in the data. DATA_FLAG_VALUE = 99999.999 END OBJECT COLUMN OBJECT COLUMN COLUMN NAME "(BIS-BOS)Z" COLUMN_NUMBER 12 DATA_TYPE ASCII_INTEGER START_BYTE 135 BYTES 10 UNIT "N/A" DESCRIPTION Please note that this value is given in the spacecraft reference frame. Data from MAG inboard and outboard sensor at 1Hz, Z COMPONENT, in nano Tesla; at certain times a significant amount of variable spacecraft background field is contained in the data. DATA_FLAG_VALUE = 99999.999 END OBJECT COLUMN OBJECT COLUMN COLUMN NAME "(BIS-BOS)T" COLUMN_NUMBER 13 DATA_TYPE ASCII_INTEGER START_BYTE 146 BYTES 10 UNIT "N/A" DESCRIPTION Please note that this value is given in the spacecraft reference frame. Data from MAG inboard and outboard sensor at 1Hz, TOTAL, in nano Tesla; at certain times a significant amount of variable spacecraft background field is contained in the data. DATA_FLAG_VALUE = 99999.999 END OBJECT COLUMN END_OBJECT END APPENDIX II: Product Design CALIBRATED_DATA Keyword SSE Type Description Example PDS_VERSION_ID SC ID PDS3 PDS3 LABEL_REVISION_NOTE SC CHAR Release and Revision information "V1.0" /* FILE RELATED INFORMATION*/ PRODUCT_ID SC CHAR Current file name, with extension (example: ) "MAG_20061115_DOY319_D001_V1.TAB" RECORD_TYPE SC ID FIXED_LENGTH FIXED_LENGTH RECORD_BYTES SC INT Record length in bytes, constant 160 FILE_RECORDS SC INT Total file length / RECORD_BYTES 86522 (closest integer greater than or equal to this value) (123 LBL-lines+ 86400 Data-lines) LABEL_RECORDS SC INT only if Data and Label are in different files "MAG_20061115_DOY319_D001_V1.LBL" SOURCE_NAME SC CHAR Source file name BAM_2006-11-15T00-00-01_DOY_319_D001_3_VSO_SAP.dat /* DATA POINTER IDENTIFICATION */ ^TABLE SC PTR only if Data and Label are in the same file 19520 (start at first entry in first data line) /* PRODUCER IDENTIFICATION */ PRODUCER_ID SC ID VEX-MAG-TEAM "VEX_MAG_TEAM" PRODUCER_FULL_NAME SC CHAR DELVA-ZAMBELLI "DELVA MAGDA, ZAMBELLI WERNER" PRODUCER_INSTITUTION_NAME SC CHAR IWF-GRAZ "INSTITUT FUR WELTRAUMFORSCHUNG - GRAZ" PRODUCT_CREATION_TIME SC TIME 2006-10-16T08:12:37 /* DATA DESCRIPTION AND IDENTIFICATION */ DATA_SET_NAME SC CHAR Description of the DATA_SET_ID (in words) "VENUS-EXPRESS VENUS MAG 3 V1.0" DATA_SET_ID SC CHAR "VEX-V/Y-MAG-3-V1.0" RELEASE_ID SC INT V1.0 1 REVISION_ID SC INT V1.0 0 PRODUCT_TYPE SC ID RDR (Reduced Data Record) "RDR" PROCESSING_LEVEL_ID SC INT CODMAC 3 3 MISSION NAME SC CHAR VENUS EXPRESS "VENUS EXPRESS" MISSION_ID SC ID VEX "VEX" INSTRUMENT_HOST_NAME SC ID VENUS EXPRESS "VENUS EXPRESS" INSTRUMENT_HOST_ID SC ID VEX "VEX" MISSION_PHASE_NAME SC CHAR VEX MISSION PHASE "PHASE1" (defined from VEX-OrbitNr List) INSTRUMENT_NAME SC CHAR MAG "MAGNETOMETER" INSTRUMENT_ID SC CHAR MAG "MAG" INSTRUMENT_TYPE SC CHAR MAGNETOMETER "MAGNETOMETER" ^INSTRUMENT_DESC SC CHAR Pointer to file: INST.CAT "^INST.CAT" /* TARGET IDENTIFICATION */ TARGET_TYPE SC CHAR PLANET "PLANET" TARGET_NAME SC CHAR VENUS "VENUS" /* TIME RELATED INFORMATION */ START_TIME SC SC TIME 2006-11-15T00:00:00.855 STOP_TIME SC TIME 2006-11-15T23:59:59.917 SPACECRAFT_CLOCK_START_COUNT SC CHAR S/C CLOCK TICS SPACECRAFT_CLOCK_STOP_COUNT SC CHAR S/C CLOCK TICS /* ORBITAL INFORMATION */ SC_SUN_POSITION_VECTOR REAL ( 141024080.54, -45879280.26, -19810607.77) SC_TARGET_POSITION_VECTOR REAL ( 1361441.35, -325381.79, -61141.68) SC_TARGET_VELOCITY_VECTOR REAL ( -3.85, 0.87, 0.14) NOTE "The values of the keywords SC_SUN_POSITION_VECTOR, SC_TARGET_POSITION_VECTOR, SC_TARGET_VELOCITY_VECTOR in Earth Eq. Coord. J2000 are valid for the time T= 00:00:00,. Distances are given in velocities in ." PERIAPSIS_TIME TIME 2006 APR 20 08:07:37 PERIAPSIS_ALTITUDE REAL ALTITUDE ABOVE VENUS NOMINAL SURFACE 256.28 SPACECRAFT_ALTITUDE REAL SPACECRAFT ALTITUDE 256.28 SUB_SPACECRAFT_LATITUDE REAL S/C LATITUDE IN PLANETOCENTRIC COORD. 295.22 SUB_SPACECRAFT_LONGITUDE REAL S/C LONGITUDE IN PLANETOCENTRIC COORD. 77.4 ORBIT_NUMBER SC INT ORBIT NR DEFINED BY VSOC 1 NOTE "The values of the keywords ORBIT_NUMBER, SUB_SPACECRAFT_LATITUDE, SUB_SPACECRAFT_LONGITUDE are given for PERIAPSIS_TIME; altitude is in , angles in degree" /* QUALITY IDENTIFICATION */ DATA_QUALITY_ID SC INT N/A "N/A" DATA_QUALITY_DESC SC CHAR N/A "N/A" /* INSTRUMENT RELATED INFORMATION*/ INSTRUMENT_MODE_ID SC INT Solar wind 1 "SW1" ^INSTRUMENT_MODE_DESC SC CHAR Pointer to file INST.CAT "^INST.CAT" /* OBJECT DEFINITIONS */ OBJECT TABLE TABLE NAME CHAR MAG CALIBRATED_DATA INTERCHANGE_FORMAT CHAR ASCII ROWS INT 86400 COLUMNS INT 9 ROW_BYTES INT 140 OBJECT COLUMN COLUMN NAME "TIME_UTC" COLUMN_NUMBER 1 DATA_TYPE TIME START_BYTE 1 BYTES 23 DESCRIPTION "UTC TIME OF OBSERVATION:" "YYYY-MM-DDTHH:MM:SS.FFF" END OBJECT COLUMN OBJECT COLUMN COLUMN NAME "BX" COLUMN_NUMBER 2 DATA_TYPE ASCII_INTEGER START_BYTE 25 BYTES 10 UNIT "NANOTESLA" UNIT_ID "nT" DESCRIPTION SPACE MAGNETIC FIELD, CALIBRATED, X COMPONENT in VSO coordinates. DATA_FLAG_VALUE = 99999.999 END OBJECT COLUMN OBJECT COLUMN COLUMN NAME "BY" COLUMN_NUMBER 3 DATA_TYPE ASCII_INTEGER START_BYTE 36 BYTES 10 UNIT "NANOTESLA" UNIT_ID "nT" DESCRIPTION SPACE MAGNETIC FIELD, CALIBRATED, Y COMPONENT in VSO coordinates. DATA_FLAG_VALUE = 99999.999 END OBJECT COLUMN OBJECT COLUMN COLUMN NAME "BZ" COLUMN_NUMBER 4 DATA_TYPE ASCII_INTEGER START_BYTE 47 BYTES 10 UNIT "NANOTESLA" UNIT_ID "nT" DESCRIPTION SPACE MAGNETIC FIELD, CALIBRATED, Z COMPONENT in VSO coordinates. DATA_FLAG_VALUE = 99999.999 END OBJECT COLUMN OBJECT COLUMN COLUMN NAME "BT" COLUMN_NUMBER 5 DATA_TYPE ASCII_INTEGER START_BYTE 58 BYTES 10 UNIT "NANOTESLA" UNIT_ID "nT" DESCRIPTION SPACE MAGNETIC FIELD, CALIBRATED, TOTAL in VSO coordinates. DATA_FLAG_VALUE = 99999.999 END OBJECT COLUMN OBJECT COLUMN COLUMN NAME "XSC" COLUMN_NUMBER 6 DATA_TYPE ASCII_INTEGER START_BYTE 69 BYTES 10 UNIT "KILOMETER" UNIT_ID "km" DESCRIPTION SPACECRAFT POSITION, X COMPONENT in VSO coordinates END OBJECT COLUMN OBJECT COLUMN COLUMN NAME "YSC" COLUMN_NUMBER 7 DATA_TYPE ASCII_INTEGER START_BYTE 80 BYTES 10 UNIT "KILOMETER" UNIT_ID "km" DESCRIPTION SPACECRAFT POSITION, Y COMPONENT in VSO coordinates END OBJECT COLUMN OBJECT COLUMN COLUMN NAME "ZSC" COLUMN_NUMBER 8 DATA_TYPE ASCII_INTEGER START_BYTE 91 BYTES 10 UNIT "KILOMETER" UNIT_ID "km" DESCRIPTION SPACECRAFT POSITION, Z COMPONENT in VSO coordinates END OBJECT COLUMN OBJECT COLUMN COLUMN NAME "RSC" COLUMN_NUMBER 9 DATA_TYPE ASCII_INTEGER START_BYTE 102 BYTES 10 UNIT "KILOMETER" UNIT_ID "km" DESCRIPTION SPACECRAFT POSITION, DISTANCE R END OBJECT COLUMN END_OBJECT END APPENDIX III: Product Design RESAMPLED_CALIBRATED_DATA Keyword SSE Type Description Example PDS_VERSION_ID SC ID PDS3 PDS3 LABEL_REVISION_NOTE SC CHAR Release and Revision information "V1.0" /* FILE RELATED INFORMATION*/ PRODUCT_ID SC CHAR Current file name, with extension (example: ) "MAG_20061115_DOY319_S004_V1.TAB" RECORD_TYPE SC ID FIXED_LENGTH FIXED_LENGTH RECORD_BYTES SC INT Record length in bytes, constant 130 FILE_RECORDS SC INT Total file length / RECORD_BYTES 21723 (closest integer greater than or equal to this value) (123 LBL-lines+ 21600 Data-lines) LABEL_RECORDS SC INT only if Data and Label are in different files "MAG_20061115_DOY319_S004_V1.LBL" SOURCE_NAME SC CHAR Source file name MAG_2006-11-15T00-00-00_DOY_319_S004_3_VSO_SAP.dat /* DATA POINTER IDENTIFICATION */ ^TABLE SC PTR only if Data and Label are in the same file 19520 (start at first entry in first data line) /* PRODUCER IDENTIFICATION */ PRODUCER_ID SC ID VEX-MAG-TEAM "VEX_MAG_TEAM" PRODUCER_FULL_NAME SC CHAR DELVA-ZAMBELLI "DELVA MAGDA, ZAMBELLI WERNER" PRODUCER_INSTITUTION_NAME SC CHAR IWF-GRAZ "INSTITUT FUR WELTRAUMFORSCHUNG - GRAZ" PRODUCT_CREATION_TIME SC TIME 2007-10-18T13:47:13 /* DATA DESCRIPTION AND IDENTIFICATION */ DATA_SET_NAME SC CHAR Description of the DATA_SET_ID (in words) "VENUS-EXPRESS VENUS MAG 4 V1.0" DATA_SET_ID SC CHAR "VEX-V/Y-MAG-4-V1.0" RELEASE_ID SC INT V1.0 1 REVISION_ID SC INT V1.0 0 PRODUCT_TYPE SC CHAR REFDR (Reformatted (Resampled)) "REFDR" PROCESSING_LEVEL_ID SC INT CODMAC 4 4 MISSION NAME SC CHAR VENUS EXPRESS "VENUS EXPRESS" MISSION_ID SC ID VEX "VEX" INSTRUMENT_HOST_NAME SC ID VENUS EXPRESS "VENUS EXPRESS" INSTRUMENT_HOST_ID SC ID VEX "VEX" MISSION_PHASE_NAME SC CHAR VEX MISSION PHASE "PHASE1" (defined from VEX-OrbitNr List) INSTRUMENT_NAME SC CHAR MAG "MAGNETOMETER" INSTRUMENT_ID SC CHAR MAG "MAG" INSTRUMENT_TYPE SC CHAR MAGNETOMETER "MAGNETOMETER" ^INSTRUMENT_DESC SC CHAR Pointer to file: INST.CAT "^INST.CAT" /* TARGET IDENTIFICATION */ TARGET_TYPE SC CHAR PLANET "PLANET" TARGET_NAME SC CHAR VENUS "VENUS" /* TIME RELATED INFORMATION */ START_TIME SC SC TIME 2006-11-15T00:00:00.855 STOP_TIME SC TIME 2006-11-15T23:59:59.917 SPACECRAFT_CLOCK_START_COUNT SC CHAR S/C CLOCK TICS SPACECRAFT_CLOCK_STOP_COUNT SC CHAR S/C CLOCK TICS /* ORBITAL INFORMATION */ SC_SUN_POSITION_VECTOR REAL ( 141024080.54, -45879280.26, -19810607.77) SC_TARGET_POSITION_VECTOR REAL ( 1361441.35, -325381.79, -61141.68) SC_TARGET_VELOCITY_VECTOR REAL ( -3.85, 0.87, 0.14) NOTE "The values of the keywords SC_SUN_POSITION_VECTOR, SC_TARGET_POSITION_VECTOR, SC_TARGET_VELOCITY_VECTOR in Earth Eq. Coord. J2000 are valid for the time T= 00:00:00,. Distances are given in velocities in ." PERIAPSIS_TIME TIME 2006 APR 20 08:07:37 PERIAPSIS_ALTITUDE REAL ALTITUDE ABOVE VENUS NOMINAL SURFACE 256.28 SPACECRAFT_ALTITUDE REAL SPACECRAFT ALTITUDE 256.28 SUB_SPACECRAFT_LATITUDE REAL S/C LATITUDE IN PLANETOCENTRIC COORD. 295.22 SUB_SPACECRAFT_LONGITUDE REAL S/C LONGITUDE IN PLANETOCENTRIC COORD. 77.4 ORBIT_NUMBER SC INT ORBIT NR DEFINED BY VSOC 1 NOTE "The values of the keywords ORBIT_NUMBER, SUB_SPACECRAFT_LATITUDE, SUB_SPACECRAFT_LONGITUDE are given for PERIAPSIS_TIME; altitude is in , angles in degrees" /* QUALITY IDENTIFICATION */ DATA_QUALITY_ID SC INT N/A "N/A" DATA_QUALITY_DESC SC CHAR N/A "N/A" /* INSTRUMENT RELATED INFORMATION*/ INSTRUMENT_MODE_ID SC INT Solar wind 1 "SW1" ^INSTRUMENT_MODE_CATALOG SC CHAR Pointer to file INST.CAT "^INST.CAT" NOTE "Please note that some of the values in the TABLE object are given in different reference frames. Where this is the case, it is indicated in the DESCRIPTION keyword of the relevant column" /* OBJECT DEFINITION */ OBJECT TABLE TABLE NAME CHAR MAG RESAMPLED_CALIBRATED_DATA INTERCHANGE_FORMAT CHAR ASCII ROWS INT 21600 COLUMNS INT 9 ROW_BYTES INT 130 OBJECT COLUMN COLUMN NAME "TIME_UTC" COLUMN_NUMBER 1 DATA_TYPE TIME START_BYTE 1 BYTES 23 DESCRIPTION "UTC TIME OF OBSERVATION:" "YYYY-MM-DDTHH:MM:SS.FFF" END OBJECT COLUMN OBJECT COLUMN COLUMN NAME "BX" COLUMN_NUMBER 2 DATA_TYPE ASCII_INTEGER START_BYTE 25 BYTES 10 UNIT "NANOTESLA" UNIT_ID "nT" DESCRIPTION SPACE MAGNETIC FIELD, RESAMPLED, CALIBRATED, X COMPONENT in VSO coordinates. DATA_FLAG_VALUE = 99999.999 END OBJECT COLUMN OBJECT COLUMN COLUMN NAME "BY" COLUMN_NUMBER 3 DATA_TYPE ASCII_INTEGER START_BYTE 36 BYTES 10 UNIT "NANOTESLA" UNIT_ID "nT" DESCRIPTION SPACE MAGNETIC FIELD, RESAMPLED, CALIBRATED, Y COMPONENT in VSO coordinates. DATA_FLAG_VALUE = 99999.999 END OBJECT COLUMN OBJECT COLUMN COLUMN NAME "BZ" COLUMN_NUMBER 4 DATA_TYPE ASCII_INTEGER START_BYTE 47 BYTES 10 UNIT "NANOTESLA" UNIT_ID "nT" DESCRIPTION SPACE MAGNETIC FIELD, RESAMPLED, CALIBRATED, Z COMPONENT in VSO coordinates. DATA_FLAG_VALUE = 99999.999 END OBJECT COLUMN OBJECT COLUMN COLUMN NAME "BT" COLUMN_NUMBER 5 DATA_TYPE ASCII_INTEGER START_BYTE 58 BYTES 10 UNIT "NANOTESLA" UNIT_ID "nT" DESCRIPTION SPACE MAGNETIC FIELD, RESAMPLED, CALIBRATED, TOTAL COMPONENT in VSO coordinates. DATA_FLAG_VALUE = 99999.999 END OBJECT COLUMN OBJECT COLUMN COLUMN NAME "XSC" COLUMN_NUMBER 6 DATA_TYPE ASCII_INTEGER START_BYTE 69 BYTES 10 UNIT "KILOMETER" UNIT_ID "km" DESCRIPTION SPACECRAFT POSITION, X COMPONENT in VSO coordinates. DATA_FLAG_VALUE = 99999.999 END OBJECT COLUMN OBJECT COLUMN COLUMN NAME "YSC" COLUMN_NUMBER 7 DATA_TYPE ASCII_INTEGER START_BYTE 80 BYTES 10 UNIT "KILOMETER" UNIT_ID "km" DESCRIPTION SPACECRAFT POSITION, Y COMPONENT in VSO coordinates. DATA_FLAG_VALUE = 99999.999 END OBJECT COLUMN OBJECT COLUMN COLUMN NAME "ZSC" COLUMN_NUMBER 8 DATA_TYPE ASCII_INTEGER START_BYTE 91 BYTES 10 UNIT "KILOMETER" UNIT_ID "km" DESCRIPTION SPACECRAFT POSITION, Z COMPONENT in VSO coordinates. DATA_FLAG_VALUE = 99999.999 END OBJECT COLUMN OBJECT COLUMN COLUMN NAME "RSC" COLUMN_NUMBER 9 DATA_TYPE ASCII_INTEGER START_BYTE 102 BYTES 10 UNIT "KILOMETER" UNIT_ID "km" DESCRIPTION SPACECRAFT POSITION, R COMPONENT. DATA_FLAG_VALUE = 99999.999 END OBJECT COLUMN END_OBJECT END