ENVISAT

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ENVISAT OVERVIEW 6 MONTHS IN ORBIT
J. Louet ENVISAT Programme Manager ESA ESTEC
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Launch, 1st March 2002, 10759 UT

• Separation at H0 26 minutes
• High precision injection
• Altitude within 100 meters
• Inclination within 13 millidegrees
• Solar array deployment within Perth coverage,
  completed at H070
• Attitude acquisition completed at H080 within
  Kerguelen coverage
• Solar array rotation release on the next
  descending pass
• above 8000 watts of energy

All launch critical activities completed
successfully
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Launch Early Orbit Phase

• Deployment of the ASAR antenna completed by 5
  March
• Activation of the Payload Equipment Bay and
  Payload Module Computer, 6 March
• Activation of on board Solid State Recorders and
  X band data links 6 March with successful
  reception at Kiruna and Matera
• ARTEMIS Ka band antenna mast deployed 7 March, no
  communication attempt with ARTEMIS, planned for
  later on during the commissioning phase.
• Satellite attitude control converged in yaw
  steering mode, ready for instrument activation,

Successful end of the LEOP phase, on schedule, 7
March
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Instrument Activation

• Switch-on of Instrument Control Units
• ASAR 7 March
• GOMOS 8 March
• AATSR, MERIS, RA-2 9 March
• MIPAS, SCIAMACHY 11 March
• DORIS/MWR 13 March
• First Instrument activations
• RA-2 in routine measurement mode 12 March
• ASAR first Cal mode (Module Stepping) 11 March
• ASAR first Wave mode 12 March
• ASAR first HR mode (Image and Wide Swath) 13
  March

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Organisation Teams Boards
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Organisation contd
Satellite Operation
CAL/VAL
Astrium supporting engineers
FOS GS teams
CAL/VAL
CAL/VAL
Report
Report
Commissioning Management Team
Satellite operations and performance Team
Instrument Performance Team
SODAP or CAL-VAL plans - GSOCP
Report
SODAP or CAL-VAL plans and GSOCP
Mission Plan
Products
Ground Segment Team
Payload Data Acquisition
FOS MPS Team
PDS Teams
SODAP or CAL-VAL plans and GSOCP
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First Check-up of the Earth 28 March 2002
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SODAP Review 16-17 April 2002 at ESOC

• All instruments operating (coolers being
  activated for AATSR, still some doors to be
  opened on SCIAMACHY)
• Mission Planning activated at PDS and FOS,
  (actions taken to solve the remaining issues SSR
  dump and link operation control, GOMOS operation
  planning tools, ASAR operation programming, etc)
• PDS Problems (lack of robustness identified,
  incomplete data recovery, priority to be given to
  the complete level 0 recovery and serving the Cal
  groups)

System ready to support the calibration activities
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Major Operation Issues after SODAP

• Mission Planning Issues have been solved (at FOS
  and PDS)
• PMC software did trigger 3 complete switch-off of
  the payload over the May-early June timeframe,
  very stable since then
• Various problems encountered with the
  instruments, not exhaustive
• ASAR on board timing anomalies
• GOMOS CCD sensitivity to protons increasing the
  dark current background, decision to operate the
  CCD at a lower temperature
• RA-2 corrections of the on board tracker and the
  S band echo accumulation anomaly from time to
  time
• DORIS/MWR ICU wrong handling of SEUs
• MIPAS procedure to unblock the interferometer and
  then the anomaly induced by the cooler vibration
  control device, ice forming on the detector
• SCIAMACHY ICU anomalies and the ice forming
  (especially channels 7 and 8).

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Overall Status Today

• Satellite Instruments
• Excellent stability and availability of the
  service module and of the Payload Module
  (sustained operation of the PMC since mid June)
• Excellent and stable performances of the
  instruments, most of the small anomalies
  encountered in orbit already corrected.
• Calibration validation Activities
• On schedule despite the encountered difficulties
  with data retrieval an delivery from the PDS
• Calibration Review 9-13 September 2002
• Validation Workshop 9-13 December 2002 (to be
  kept on schedule)

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Near Real Time Data Processing Dissemination
X-Band
SVALBARD
KIRUNA PDHS
Near Real Time processing
Data Dissemination by Satellite using an EUTELSAT
DVB channel
ESRIN PDCC PDHS
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Problems Encountered with the PDS

• Difficulty to produce the complete level 0 data
  set (Kiruna scenario workload)
• All production dependent upon the availability of
  the Kiruna PDHS-K
• Difficulty to achieve the robustness of the
  system (despite significant progress, in
  particular with the production level 0, 1b and 2
  basically solved)
• Data product archiving and distribution not
  robust enough (loss of products, media copying
  less reliable than online distribution DDS
  providing and excellent service)
• Phasing in of LRAC and PACs delayed by the PDHS-K
  encountered problems

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PDS Next Steps

• Work Plan put in place to recover the situation
  over the last quarter 2002
• Priority still given to Cal/Val members, while
  starting other PIs phase in
• Need to ensure complete level 0 production at the
  PDHS and feeding of the LRAC for level 0 and
  level 1b consolidation
• Need to ensure all ASAR HR and MERIS FR level 0
  production at the PDHS and feeding of the PACs
  for offline image production
• Use of the PACs in the archiving and media
  duplication of level 1b and 2 products to the
  Cal/val Pis and other users (starting with PDHS
  products)
• Introduction of the Kiruna-Svalbard scenario mid
  October

ENVISAT Mission Operational End 2002, for a
Subset of Products Services