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The Hipparcos and Tycho Catalogues The Hipparcos and Tycho Catalogues SP±1200 June 1997 The Hipparcos and Tycho Catalogues Astrometric and Photometric Star Catalogues derived from the ESA Hipparcos Space Astrometry Mission A Collaboration Between the European Space Agency and the FAST, NDAC, TDAC and INCA Consortia and the Hipparcos Industrial Consortium led by Matra Marconi Space and Alenia Spazio European Space Agency Agence spatiale europeenne Cover illustration: an impression of selected stars in their true positions around the Sun, as determined by Hipparcos, and viewed from a distant vantage point. Inset: sky map of the number of observations made by Hipparcos, in ecliptic coordinates. Published by: ESA Publications Division, c/o ESTEC, Noordwijk, The Netherlands Scienti®c Coordination: M.A.C. Perryman, ESA Space Science Department and the Hipparcos Science Team Composition: Volume 1: M.A.C. Perryman Volume 2: K.S. O'Flaherty Volume 3: F. van Leeuwen, L. Lindegren & F. Mignard Volume 4: U. Bastian & E. Hùg Volumes 5±11: Hans Schrijver Volume 12: Michel Grenon Volume 13: Michel Grenon (charts) & Hans Schrijver (tables) Volumes 14±16: Roger W. Sinnott Volume 17: Hans Schrijver & W. O'Mullane Typeset using TEX (by D.E. Knuth) and dvips (by T. Rokicki) in Monotype Plantin (Adobe) and Frutiger (URW) Film Production: Volumes 1±4: ESA Publications Division, ESTEC, Noordwijk, The Netherlands Volumes 5±13: Imprimerie Louis-Jean, Gap, France Volumes 14±16: Sky Publishing Corporation, Cambridge, Massachusetts, USA ASCII CD-ROMs: Swets & Zeitlinger B.V., Lisse, The Netherlands Publications Management: B. Battrick & H. Wapstra Cover Design: C. Haakman 1997 European Space Agency ISSN 0379±6566 ISBN 92±9092±399-7 (Volumes 1±17) Price: 650 D¯ ($400) (17 volumes) 165 D¯ ($100) (Volumes 1 & 17 only) Volume 2 The Hipparcos Satellite Operations Compiled by: M.A.C. Perryman & K.S. O'Flaherty (ESA±ESTEC) D. Heger (ESA±ESOC) & A.J.C. McDonald (ESOC/Logica UK Ltd) with the support of The Hipparcos Science Team, M. Bouffard (Matra Marconi Space), and B. Strim (Alenia Spazio) Launch of the Hipparcos Satellite by Ariane 4 Flight V33, 8 August 1989 (Photo: CSG Kourou) ix Volume 2: The Hipparcos Satellite Operations Contents Foreword...............................xiii Prologue................................1 Section A: Background 1. Overview of the Hipparcos Satellite . ............... 11 1.1.OperatingPrinciple....................... 11 1.2. Constraints and Properties of the Nominal Orbit .......... 17 1.3. Satellite Environmental Conditions . ............... 18 1.4.AttitudeControlConcept.................... 21 1.5.DataHandlingandProcessing.................. 22 1.6.OperationalConcept...................... 24 1.7. Satellite Mechanical and Electrical Design ............. 25 1.8.GroundSegmentOverview................... 29 2.ThePayload:OverviewandOpticalElements ............. 33 2.1.Introduction.......................... 33 2.2.PayloadCon®gurationandLayout................ 35 2.3.PayloadHardware....................... 41 2.4.TelescopeMirrors....................... 43 2.5.ModulatingGridandBaf¯eUnit................. 47 2.6.RelayLensSystems....................... 56 3.ThePayload:Detectors,Electronics,andStructure........... 65 3.1.Detectors........................... 65 3.2.PayloadElectronicsandMechanisms............... 71 3.3.Baf¯es............................ 75 3.4.PayloadStructure....................... 79 Section B: Launch and Early Orbit Phases 4.LaunchandRevisedMissionDe®nition................ 85 4.1.Introduction.......................... 85 4.2.OperationsUntilRevisedMissionImplementation......... 86 4.3. Apogee Boost Motor Failure Investigations ............ 87 4.4.RevisedMissionDe®nition................... 88 4.5. Ground Station Utilisation ................... 91 4.6.MissionPlanning........................ 94 4.7. Orbit Manoeuvres and Commissioning Activities .......... 97 x 5.InitialPayloadCalibration......................103 5.1.CalibrationPlan........................103 5.2.DetectorNoise.........................104 ..traprigeSiRsos ................106 5.3.StarMapperSingle-SlitResponse 5.4.InitialImageDissectorTubePiloting...............107 5.5.TransverseandLongitudinalOffsets...............111 5.6.Focusing...........................112 5.7.InstantaneousFieldofViewPro®le................113 ..hoaiiy.........................1145.8.Chromaticity 5.9. Straylight . ..........................115 6. The Operational Orbit ........................117 6.1. Orbital Elements ........................117 6.2.RadiationEnvironment.....................119 6.3.Eclipses............................119 6.4.Occultations..........................121 6.5.GroundStationCoverage....................121 6.6.PerturbingTorques.......................122 6.7.LossofReal-TimeAttitudeDetermination ............122 6.8.Micrometeoroids........................123 7.RadiationBackgroundandRelatedEffects...............127 7.1.Introduction..........................127 7.2.TheRadiationEnvironmentinSpace...............128 7.3. Modelling the Radiation Dose Absorbed by the Satellite . ....132 7.4.EffectsoftheRadiationBackgroundontheMission.........135 Section C: Interfaces with the Scienti®c Consortia 8. The Observation Programme and Interface with the INCA Consortium . 143 8.1.ScanningLaw.........................143 8.2.StarObservations .......................150 8.3.InputCatalogueConsortiumInterfaceswithESOC.........156 8.4.ProgrammeStarFileGeneration.................160 8.5.ModulationStrategy......................163 9.InterfaceswiththeDataReductionConsortia..............167 9.1.Introduction..........................167 9.2.DataDistributionfromESOCtotheConsortia ..........169 9.3. Data from FAST to ESOC in Support of Satellite Operations ....175 9.4. Data from NDAC to ESOC in Support of Satellite Operations ....176 xi Section D: Payload and Spacecraft Performances 10.RoutineCalibrationandPayloadEvolution...............179 10.1. Routine Monitoring Activities at ESOC .............179 10.2.PayloadCalibration......................182 10.3.FocusEvolution .......................185 10.4.PhotometricEvolution.....................193 10.5. Payload Modelling ......................193 10.6. Star Mapper Sensitivity during Suspended Operations . ....207 11.SolarArrayPerformance.......................209 11.1.Introduction.........................209 11.2.PowerSubsystemDegradation.................211 11.3.SolarArrayDegradation....................214 11.4.Eclipse-InducedAttitudeJitter.................224 12.ThermalControl..........................227 12.1.Introduction.........................227 12.2.HeaterDesign........................229 12.3.PayloadThermalControlHistory................229 12.4. Thermal Anomalies and the Basic Angle .............232 Section E: Real-Time Attitude Control and Determination 13. Attitude and Orbit Control System and Performances ..........237 13.1. Functions of the Attitude and Orbit Control System ........237 13.2.EquipmentDescription....................238 13.3.ReactionControlAssembly...................241 13.4.InertialReferenceUnit.....................244 13.5.GyroPerformances......................245 13.6.GyroRelatedGroundInvestigations...............249 13.7.GasConsumption.......................252 13.8.NormalModeController....................252 13.9.ThrusterMonitoringandNormalModeSoftwarePatch......255 13.10.DisturbanceTorques.....................256 13.11.Real-TimeAttitudeDetermination...............256 14.Real-TimeAttitudeDeterminationwithThreeGyros..........257 14.1.IntroductionandOverallConcept................257 14.2. On-Board Real-Time Attitude Determination using Three Gyros . 260 14.3.On-GroundReal-TimeAttitudeDetermination..........265 14.4.Real-TimeAttitudeDeterminationPerformance..........281 xii 15.Real-TimeAttitudeDeterminationwithTwoGyros...........287 15.1.Two-GyroOperationsDevelopmentHistory...........287 15.2.OperationalRequirements...................289 15.3.On-BoardSoftware......................291 15.4.On-GroundSoftware.....................294 15.5.OperationalExperience....................300 16.Real-TimeAttitudeDeterminationwithZeroGyros...........305 16.1. Activities during Suspended Operations .............305 16.2.On-BoardSoftware......................307 16.3.On-GroundSoftware.....................311 16.4.OperationalExperience....................315 Section F: End of Mission 17. End of Mission Activities and Conclusions ...............317 17.1. End-of-Life History ......................317 17.2. End-of-Life Tests .......................318 17.3. Satellite Reliability Assessment . ...............322 17.4. Data Archiving Policy .....................322 17.5. Miscellaneous Considerations . ...............322 17.6. Overall Success of the Hipparcos Mission .............329 Appendices AppendixA.TheESA-ESOCOperationsTeam..............331 Appendix B. Satellite Anomalies .....................337 AppendixC.References.........................349 AppendixD.Bibliography........................351 AppendixE.TheHipparcosMissionCosts ................379 Appendix F. The Hipparcos Satellite During Development ..........383 Index.................................397 xiii Foreword The Hipparcos astrometry mission was accepted within the European Space Agency's scienti®c programme in 1980. The Hipparcos satellite was designed and constructed under ESA responsibility by a European industrial consortium led by Matra Marconi Space (France) and Alenia Spazio (Italy), and launched by Ariane 4 ¯ight V33 on 8 August 1989. High-quality scienti®c data were acquired between November 1989 and March 1993,
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