PDS_VERSION_ID = PDS3 RECORD_TYPE = STREAM RELEASE_ID = 0001 REVISION_ID = 0000 INSTRUMENT_HOST_NAME = "MARS EXPRESS" INSTRUMENT_HOST_ID = "MEX" MISSION_NAME = "MARS EXPRESS" DATA_SET_ID = "MEX-M-ASPERA3-2-EDR-ELS-V1.0" OBJECT = TEXT PUBLICATION_DATE = 2005-05-31 NOTE = "MEX ASPERA-3 ELS EDR ERRATA" END_OBJECT = TEXT END MEX ASPERA-3 ELS EDR ERRATA This file describes the known errors and anomalies for the Electron Spectrometer (ELS) EDR (RAW or Cnts/Accum) data set on this volume. Concerning ELS NEV Data: Before 2003/190 (09 July 2003), operational engineering tests were being executed on the ELS instrument. Before 2100 hours on that date, the ELS science data should be all zero (except for day 2003/183, 02 July 2003, between 0100 hours and 0200 hours). For all times other than the 2003/183 (2003-07-02) time listed above, ELS was undergoing the Near Earth Verification tests. These tests adjusted the ELS instrument voltages and the ELS science data was monitored to be sure that the science data were all zero. If ELS science data had not been zero, it would have been an indication that there was something wrong with the instrument. Thus, the zeroes in the ELS science data are normal and expected during these times. The exception for day 2003/183 (02 July 2003) between 0100 hours and 0200 hours was when the deflection plates were not stepping and the instrument voltages were increased such that a science signal could be seen. Since the ELS was not sweeping but held at a fixed value, there should be science data only at one energy (although the numeric value for each sector should be different). Science data values should show in all sectors of ELS, not just in sector zero. Tests were to include sweeping of the deflection plates at this time, but a small bug in the operations software prevented sweeping. This was not fixed until after 2100 hours on day 2003/190 (09 July 2003). Concerning ELS January 2004 Data: The Mars Express commissioning period for ASPERA-3 occurred in January 2004. Since operational engineering tests were being executed on the ELS instrument during this time, some of the ELS science data are all zeroes. The zeroes are normal and expected during January 5, 12, and 14, 2004. If the ELS science data had not been zero during these times, it would have been an indication that there was something wrong with the instrument. Additional Information in the DOCUMENT Directory: Although PDS requires documents in the DOCUMENT directory to have an ASCII form, there are several documents in PDF format only: 1. ASPERA3_FLIGHT_PERF.PDF - The ASPERA-3 Flight Performance Report Document (submitted to ESA) 2. ASPERA3_MEX_EXP.PDF - The Analyzer of Space Plasmas and Energetic Atoms (ASPERA-3) for the Mars Express Mission (Draft of ESA Publication) 3. ASPERA3_SENSOR_FRAMES.PDF - The ASPERA-3 Sensor Numbering and frames suppport document. 4. ME_ASP_DS_0002.PDF - The ASPERA-3 Design Description document. 5. ME_ASP_MA_0003_V3_0.PDF - The ASPERA-3 Flight Operation Manual. 6. ELS_CALIBRATION_REPORT.PDF - The ASPERA-3 Electron Spectrometer (ELS) Calibration Report. These documents add to the understanding of the ASPERA-3 experiment, but are considered non-critical for understanding the contents and usage of the ASPERA-3 archived data sets. All critical information for understanding the contents and usage of the ASPERA-3 archived data sets are included in the Catalog files, data labels, or some other ASCII form.