News

30 April 2016: SOST-DLR Phase F has ended

08 March 2013: Update of SODAP information

31 January 2013: Update of data quality information

09 August 2012: SCIAMACHY Preliminary In-orbit Mission Report

31 July 2012: SOST website migration

09 May 2012: ENVISAT mission ended!

10 April 2012: ENVISAT anomaly

04 April 2012: SCIAMACHY cold restart

02 March 2012: March/April planning

29 February 2012: Orbit control manoeuvre

23 February 2012: SCIAMACHY in HEATER/REFUSE mode and recovery

14 February 2012: March planning

24 January 2012: ENVISAT service module anomaly

17 January 2012: SCIAMACHY in HEATER/REFUSE mode and recovery

20 December 2011: Operations support over Christmas/New Year

19 December 2011: Modified January/February planning

02 December 2011: January/February planning

11 November 2011: December planning

14 October 2011: ENVISAT manoeuvre and attitude mode change

23 September 2011: SCIAMACHY in HEATER/REFUSE mode and recovery

08 September 2011: SCIAMACHY in HEATER/REFUSE mode and recovery

30 August 2011: October/November planning

29 August 2011: SCIAMACHY in HEATER/REFUSE mode and recovery

17 July 2011: SCIAMACHY in HEATER/REFUSE mode and recovery

12 July 2011: August/September planning

12 June 2011: June/July planning

27 May 2011: SCIAMACHY transfer to STANDBY and recovery

12 April 2011: April/May/June planning (cycles 102/103)

04 MApril 2011: ENVISAT payload switch-off and recovery

23 March 2011: SCIAMACHY transfer to STANDBY and recovery

18 February 2011: March/April planning

11 January 2011: New final flight configuration

23 December 2010: Operations support over Christmas/New Year

10 December 2010: January/February planning

22 November 2010: Transfer to R/W WAIT and recovery

05 November 2010: Transfer to R/W WAIT and recovery

21 October 2010: October/November/December planning

12 October 2010: ENVISAT orbit manoeuvre and SCIAMACHY operations

06 October 2010: SCIAMACHY transfer to STANDBY and recovery

26 August 2010: Short unplanned MEASUREMENT IDLE phase

24 August 2010: SCIAMACHY transition to HTR/RF and recovery

11 August 2010: New final flight configuration

10 August 2010: Transfer to HTR/RF and recovery

10 August 2010: September/October planning

14 July 2010: August planning

02 July 2010: Next orbit control manoeuvre

17 June 2010: New final flight configuration

07 June 2010: July planning

26 May 2010: Platform attitude anomaly

23 April 2010: Next orbit control manoeuvre

15 April 2010: Transfer to R/W WAIT and recovery

12 April 2010: May/June planning

04 March 2010: SCIAMACHY transition to R/W WAIT and recovery

22 February 2010: Transfer to HTR/RF and recovery

12 February 2010: March/April planning

12 February 2010: Next orbit control manoeuvre

01 February 2010: SCIAMACHY transition to R/W WAIT and recovery

20 January 2010: New monitoring features - scanner monitoring, detector, OBM and PMD temperature summaries

18 January 2010: SCIAMACHY transition to STANDBY and recovery

12 January 2010: Platform attitude anomaly

21 December 2009: Operations support over X-mas/New Year

07 December 2009: January/February planning

07 December 2009: Next orbit control manoeuvre

19 November 2009: Transfer to R/W WAIT and recovery

06 October 2009: November/December planning

25 September 2009: Next orbit control manoeuvre

10 August 2009: SCIAMACHY transition to HTR/RF and recovery

06 August 2009: September/October planning

20 July 2009: August planning

17 July 2009: Next Orbit control manoeuvre

26 June 2009: Successful Venus observation

23 June 2009: SCIAMACHY transition to HTR/RF and recovery

17 June 2009: SCIAMACHY transition to STANDBY and recovery

05 June 2009: SCIAMACHY transition to STANDBY and recovery

29 April 2009: June/July planning

06 April 2009: Next Orbit control manoeuvre

01 April 2009: May planning

01 April 2009: SOST website availability

20 March 2009: cL0 data availability 2002-2007

06 March 2009: Platform attitude anomaly

06 March 2009: SCIAMACHY transition to STANDBY and recovery

16 February 2009: Platform attitude anomaly

12 February 2009: March/April planning

28 January 2009: Light path monitoring

22 January 2009: Orbit control manoeuvre

07 January 2009: Decontamination status

22 December 2008: Operations support over X-mas/New Year

19 December 2008: Decontamination started

12 December 2008: January/February planning

17 November 2008: December planning

14 November 2008: Orbit control manoeuvre

03 November 2008: Transfer to HTR/RF and recovery

30 October 2008: Limb_Mesosphere_Thermosphere planning information

16 October 2008: New ATC configuration

10 October 2008: New final flight configuration

10 October 2008: November planning

09 September 2008: Orbit control manoeuvre

24 August 2008: SCIAMACHY transition to STANDBY and recovery

12 August 2008: September/October planning

04 July 2008: August planning

20 June 2008: SOST website modification

16 June 2008: July planning

16 June 2008: Next orbit control manoeuvre

09 May 2008: June planning

21 April 2008: Next orbit control manoeuvre

03 April 2008: May planning

14 March 2008: Platform attitude anomaly

14 February 2008: March/April planning

11 February 2008: Next orbit control manoeuvre

30 January 2008: SCIAMACHY state search engine

18 January 2008: ENVISAT HSM anomaly and recovery

21 December 2007: Operations support over X-mas/New Year

17 December 2007: January/February planning

10 December 2007: Another service module maintenance

05 December 2007: SCIAMACHY back to MEASUREMENT

03 December 2007: SCIAMACHY transition to STANDBY and recovery

30 November 2007: Orbit control manoeuvre and service module maintenance

19 November 2007: December planning

09 October 2007: November planning

28 September 2007: ENVISAT recovered

25 September 2007: ENVISAT service module anomaly

21 September 2007: Orbit control manoeuvre and service module maintenance

14 August 2007: SOST web support in vacation period

07 August 2007: September/October planning

01 August 2007: SCIAMACHY recovered

30 July 2007: SCIAMACHY in HTR/RF - recovery started

23 July 2007: Unavailability history for 2002 added

12 July 2007: August planning

12 June 2007: Next orbit control manoeuvre

02 July 2007: SCIAMACHY recovered

29 June 2007: Transfer to HTR/RF

25 June 2007: Subsolar window unobscured again

18 June 2007: July planning

18 June 2007: Subsolar window currently obscured

21 May 2007: Short unplanned MEASUREMENT IDLE phase

10 May 2007: June planning

30 March 2007: Figures of SCIAMACHY book

30 March 2007: Next orbit control manoeuvre

12 March 2007: April/May planning

14 February 2007: March planning

06 February 2007: SCIAMACHY book online version

05 February 2007: Light path monitoring modification

22 January 2007: Next orbit control manoeuvre

21 December 2006: Operations support over X-mas/New Year

18 December 2006: ENVISAT recovered

13 December 2006: ENVISAT payload switch-off

12 December 2006: January/February planning

24 November 2006: Planned ENVISAT payload switch-off

24 November 2006: SCIAMACHY recovered

23 November 2006: Transfer to HTR/RF (with update)

10 November 2006: December planning

12 October 2006: November planning

06 October 2006: cL0 data availability updated

29 September 2006: ENVISAT Ka-band antenna recovery and data acquisition

27 September 2006: ENVISAT Ka-band antenna anomaly

11 September 2006: ENVISAT recovered

08 September 2006: ENVISAT payload switch-off

07 September 2006: Next orbit control manoeuvre

29 August 2006: October planning

21 August 2006: September planning modified

20 July 2006: September planning

10 July 2006: Spectral monitoring results download

20 June 2006: SCIAMACHY book printed

12 June 2006: July/August planning

29 May 2006: Transfer to HTR/RF and recovery (with update)

19 April 2006: SCIACHAMY recovery after April 16 anomaly

16 April 2006: Transfer to HTR/RF

13 April 2006: Transfer to HTR/RF and recovery

12 April 2006: May/June planning

10 April 2006: ENVISAT recovered

06 April 2006: ENVISAT payload swith-off

27 March 2006: Next orbit control manoeuvre

07 February 2006: March/April planning

07 February 2006: Transfer to HTR/RF and recovery

06 February 2006: Transfer to R/W WAIT and recovery

09 January 2006: Next orbit control manoeuvre

22 December 2005: Operations support over X-mas/New Year

16 December 2005: SOST webserver has moved

12 December 2005: January/February planning

16 November 2005: No decontamination

07 November 2005: December planning

29 September 2005: November planning

24 August 2005: New feature - cL0 availability

23 August 2005: Next orbit control manoeuvre

29 July 2005: September/October planning

28 July 2005: Spectral light path monitoring results

14 June 2005: July/August planning

13 May 2005: Recovery started

12 May 2005: Transfer to R/W WAIT

10 May 2005: Back in MEASUREMENT

09 May 2005: June planning

09 May 2005: Transfer to HTR/RF and recovery

08 April 2005: Instrument availability display added in operations summary

04 April 2005: May planning

10 March 2005: Next orbit control manoeuvre

18 February 2005: March to April planning

20 January 2005: February to March planning

20 January 2005: Modified limb state 32 during TROCCINOX-2 campaign

10 January 2005: Decontamination status

23 December 2004: Operations support over X-mas/New Year

21 December 2004: Next orbit control manoeuvre

21 December 2004: Decontamination started

12 December 2004: January to February planning

25 November 2004: December to January planning

24 November 2004: Reference time information added

17 November 2004: Transfer to HTR/RF and recovery

11 November 2004: Next decontamination

21 October 2004: November to December planning

15 October 2004: Mozilla access to geolocation information restored

08 October 2004: Limited access to to geolocation information

04 October 2004: Transfer to R/W WAIT and recovery

27 September 2004: October to November planning

27 September 2004: Back in MEASUREMENT

23 September 2004: Transfer to HTR/RF and recovery

15 September 2004: Next orbit control manoeuvre

13 September 2004: Manoeuvre information

03 August 2004: August to October planning

06 July 2004: SCIAMACHY back to measurement

05 July 2004: Transfer to R/W WAIT mode

02 July 2004: Decontamination status

30 June 2004: July/August planning

22 June 2004: Attitude anomaly

18 June 2004: Decontamination starts today

17 May 2004: June/July planning

17 May 2004: Next decontamination

10 May 2004: Transfer to HTR/RF and recovery

26 April 2004: May/June planning

06 April 2004: Measurement interrupt due to orbit control manoeuvre

30 March 2004: Operations summary added to website

24 March 2004: April/May planning

24 March 2004: Detector 7 & 8 temperature monitoring enabled

11 March 2004: Limb with higher vertical sampling

11 March 2004: Trim heater adjustment

20 February 2004: March/April planning cycle

03 February 2004: Measurement interrupt

29 January 2004: Next planning cycle

21 January 2004: Return to operations

20 January 2004: Transfer to HTR/RF and recovery

07 January 2004: Decontamination status

07 January 2004: Transfer to R/W WAIT mode and recovery

23 December 2003: Operations support over X-mas/New Year

23 December 2003: SCIAMACHY back to measurement

22 December 2003: Recovery and a second HTR/RF

19 December 2003: Transfer to HTR/RF and recovery

18 December 2003: Decontamination started

08 December 2003: ENVISAT attitude mode

08 December 2003: SCIAMACHY back to operations

05 December 2003: SCIAMACHY recovery in progress

03 December 2003: ENVISAT payload switch-off

02 December 2003: Planning November 2003 to February 2004

28 November 2003: Next decontamination

20 November 2003: New monitoring table

05 November 2003: Solar activity and light path monitoring

05 November 2003: Parameter table update

24 October 2003: Measurement interrupt

24 October 2003: November/December planning

17 October 2003: Possible measurement interrupt

15 October 2003: Improved limb/nadir matching implemented

29 September 2003: Limb/nadir matching implementation

29 September 2003: October/November planning

10 September 2003: October planning, part 1

08 September 2003: ENVISAT recovery/SCIAMACHY back to operations

05 September 2003: ENVISAT payload switch-off

03 September 2003: Limb/nadir matching test

01 September 2003: Decontamination status

18 August 2003: Transfer to HTR/RF and recovery

12 August 2003: Decontamination started

29 July 2003: Next planning cycle

28 July 2003: SCIAMACHY back to operations

25 July 2003: SCIAMACHY in HTR/RF

11 July 2003: Limb_mesophere re-established

11 July 2003: Next decontamination

09 July 2003: Timelines for all mission scenarios

01 July 2003: Next planning cycle

17 June 2003: OCR 9 to be repeated

22 May 2003: OCR 8 / limb_mesosphere

22 May 2003: June, part 2 / July planning

21 May 2003: Decontamination started

20 May 2003: June planning, part 1

19 May 2003: May reduced operations

08 May 2003: May operations

24 April 2003: Completion of delta SODAP measurements

10 April 2003: Next planning cycle

04 April 2003: Non-nominal decontamination

03 April 2003: More OCR information

03 April 2003: April planning, part 2

31 March 2003: Nadir swath modification

21 March 2003: Planning modification

21 March 2003: SCIAMACHY off ..... and on

19 March 2003: April planning, part 1

19 March 2003: SCIAMACHY back to operations

17 March 2003: Next decontamination

15 March 2003: ENVISAT payload switch-off

14 March 2003: Final Flight state description

14 March 2003: Monitoring information

26 February 2003: OCR description

24 February 2003: Modified planning

24 February 2003: SCIAMACHY back to operations

20 February 2003: SCIAMACHY recovery and ENVISAT payload switch-off

17 February 2003: Transfer to R/W WAIT mode

12 February 2003: New planning files

04 February 2003: Time reference information added

16 January 2003: Final flight state tables available

09 January 2003: New planning files

07 January 2003: HEATER/REFUSE and recovery

20 December 2002: Operations support over X-mas/New Year

17 December 2002: December planning - part 3

17 December 2002: SOST website inaccessible tomorrow

16 December 2002: ASM diffuser state modified

12 December 2002: Another HEATER/REFUSE and recovery

06 December 2002: December planning - part 2

06 December 2002: Final flight configuration achieved

04 December 2002: Another HEATER/REFUSE and recovery

02 December 2002: ..... and back to MEASUREMENT

02 December 2002: SCIAMACHY in HEATER/REFUSE

27 November 2002: December planning

21 November 2002: SCIAMACHY Realtime Orbit Display

21 November 2002: Full nadir/limb matching achieved

20 November 2002: Recovery after Leonids

18 November 2002: Test of Nadir states with dark current

14 November 2002: SCIAMACHY data interrupt and recovery

12 November 2002: New feature on web-page

12 November 2002: Leonid meteor shower

28 October 2002: ICU patch executed

28 October 2002: November measurement plans available

24 October 2002: Bug in co-adding table corrected

11 October 2002: Geolocation in orbits 3324-3329 updated

24 September 2002: October measurement plans available

16 September 2002: Modified geolocation maps for Falcon campaign

08/11 September 2002: SCIAMACHY OCM/PMC upgrade interrupt

28/29 August 2002: SCIAMACHY off.... and on again

14 August 2002: September measurement plan available

02 August 2002: Validation measurements started and geolocation update

24 July 2002: Geolocation Sun and moon occultation

23 July 2002: SCIAMACHY August measurement plan

17 July 2002: News about geolocation

16 July 2002: SCIAMACHY is back in MEASUREMENT mode

15 July 2002: MCMD CCA check error strikes back

09 July 2002: Modified geolocation information

25 June 2002: Ancillary MCMD spacing and geolocation

20 June 2002: SCIAMACHY Elevation Cover released

18 June 2002: SCIAMACHY ..... and on again

17 June 2002: SCIAMACHY ..... and off again

14 June 2002: SCIAMACHY back in SODAP operations

13 June 2002: SCIAMACHY switched off again

11 June 2002: SCIAMACHY recovery

06 June 2002: ENVISAT payload safing

26 May 2002: SCIAMACHY switched to RESET/WAIT

17 May 2002: SCIAMACHY switched to RESET/WAIT

13 May 2002: SCIAMACHY recovery started

11 May 2002: ENVISAT payload safing

03 May 2002: SCIAMACHY 'sub-solar mystery' explained

28-30 April 2002: SCIAMACHY in HEATER/REFUSE mode

24 April 2002: Kiruna coverage parameters available

23 April 2002: Swath Visualization file access available

15 April 2002: Successful opening of SRC door

13/14 April 2002: SCIAMACHY anomaly causes brief interrupt of operations

5 April 2002: First 'real' Sun and limb measurements in Measurement Window 2

3 April 2002: Successful opening of azimuth cover

22 March 2002: LLI prediction started and SAA flag in ROE Excerpt

17 March 2002: First MPS driven timeline operations

15 March 2002: First successful measurements of on-board light sources performed

12 March 2002: Successful SCIAMACHY switch-on and updated SCIAMACHY SODAP overview

6 March 2002: First 'real' mission planning information - ROE Excerpt & SODAP Plans

25 February 2002: Test Reference Orbit Event File Excerpt

25 February 2002: SCIAMACHY SODAP details

20 February 2002: SCIAMACHY SODAP overview

20 February 2002: SOST goes online




30 April 2016: SOST-DLR Phase F has ended

Today the phase F for the DLR part of the SCIAMACHY Operations Support has ended. In a two-year phase from May 2014 to April 2016 all relevant operations and instrument performance information, which had in the past been generated by SOST-DLR, was collected, harmonized and prepared for long-term preservation. This gives a complete overview of important system aspects of the SCIAMACHY mission.

Details are described in three documents which had been prepared in phase F by SOST. They can be found under Mission Documents. Additional operations knowhow can further be retrieved from the SOST websites which will continue to exist.

SOST-DLR greatly appreciates to have participated for more than 20 years in the exciting SCIAMACHY mission and to have contributed to its success.




08 March 2013: Update of SODAP information

Because consolidation of SODAP orbits with measurement data has become a topic for longterm data preservation, we have added to the SODAP Specific Info a SODAP Timeline Sequence list for the period orbit 197 (14th March 2002) to orbit 2203 (1st August 2002).




31 January 2013: Update of data quality information

We have updated the information concerning data quality. Now the website distinguishes between periods with degraded data quality due to thermal activities (Data Quality Thermal) and those caused by orbit manoeuvres / attitude events (Data Quality Pointing 2002-2007 and Data Quality Pointing 2008-2012).




09 August 2012: SCIAMACHY Preliminary In-orbit Mission Report

We have generated the document entitled SCIAMACHY Preliminary In-orbit Mission Report (note: The final mission report shall be prepared as part of SCIAMACHY's phase F activities and will be more comprehensive). It is available via the SOST website and can be accessed under Mission Documents.




31 July 2012: SOST website migration

In the course of preparing the phase F of the SCIAMACHY mission, the SOST website will migrate to another webserver and operating environment. This action is planned for July 31th. It shall be completely transparent for the users of the SOST website. However, if you experience a reduced performance when accessing the webpages, please let us know to fix potential inconsistencies.




09 May 2012: ENVISAT mission ended!

After one month of attempts to recover ENVISAT following the anomaly from April 8th, ESA has today declared the ENVISAT mission ended. More details can be found on ESA's news website.

How SOST will proceed will be specified in the coming weeks. Since there is a wealth of information from the areas of instrument operations and in-orbit performance required for future usage, our focus will shift to detailed analyses of certain instrument aspects and the archiving and documentation of what has been done in the past 10 years. The SOST websites will continue to exist and will even undergo modifications whenever necessary.




10 April 2012: ENVISAT anomaly

Since the Kiruna pass in orbit 52868 (April 8th, 12:28:00 UTC), the ENVISAT platform is not transmitting any telemetry or measurement data (X-band and Ka-band) anymore. There are indications that ENVISAT is in Safe Mode. Anomaly Review Boards convened to understand the problem and to decide how to proceed. Further information will be reported here once available.




04 April 2012: SCIAMACHY cold restart

Between the late afternoon of April 10th and around noon on April 11th, SCIAMACHY will be unavailable due to a Cold Restart. This activity is planned in support of an anomaly investigation concerning the Elevation Scanner Mechanism (ESM) when being controlled by the Sun Follower (SF). The exact period in modes lower than MEASUREMENT will be provided on the SOST website under Data Unavailability History once they are available.




02 March 2012: March/April planning

The planning documents for the period March 20th - April 30th, 2012 (orbit 52601-53191) can be found on the SOST webpages (OSDF, SIM_SDMOP, limb_mesosphere_thermosphere, State_Summary, limb_geolocation and nadir_geolocation).

All measurements are nominal.




29 February 2012: Orbit control manoeuvre

On March 1st in the early morning an out-of-plane ENVISAT manoeuvre is planned. The MPS schedule stops on February 29th at 21:16 UTC (orbit 52313) and will resume on March 1st at 06:47 UTC (orbit 52318).




23 February 2012: SCIAMACHY in HEATER/REFUSE mode and recovery

In orbit 52204 (February 22nd, 08:08:07 UTC) SCIAMACHY was transferred to HTR/RF mode triggered by an ASM Overcurrent (I0111 OOL). A Single Event Upset (SEU) is considered to be the cause of the anomaly.

Since the anomaly is a known feature, recovery was started immediately. In orbit 52219 (February 23rd, 09:25:00 UTC) SCIAMACHY continued the planned measurement schedule.




14 February 2012: March planning

The planning documents for the period March 1st - 20th, 2012 (orbit 52315-52600) can be found on the SOST webpages (OSDF, SIM_SDMOP, limb_mesosphere_thermosphere, State_Summary, limb_geolocation and nadir_geolocation). This planning ends with cycle 112 because starting with cycle 113 a slightly modified ENVISAT orbit will be applicable.

All measurements are nominal.




24 January 2012: ENVISAT service module anomaly

On January 23rd the ENVISAT payload has to be switched off for curing a service module memory fault. SCIAMACHY's MPS schedule stops in orbit 51772 (January 23rd, 06:45 UTC), transition back to HEATER started around 11:36 UTC the same day and measurements finally resumed in orbit 51688 (January 24th, 09:28 UTC).




16 January 2012: SCIAMACHY in HEATER/REFUSE mode and recovery

In orbit 51670 (January 16th, 03:27:20 UTC) SCIAMACHY was transferred to HTR/RF mode triggered by a SDPU_Tx buffer overflow. A Single Event Upset (SEU) is considered to be the cause of the anomaly.

Since the anomaly is a known feature, recovery was started immediately. In orbit 51687 (January 17th, 08:45:00 UTC) SCIAMACHY continued the planned measurement schedule.




20 December 2011: Operations support over Christmas/New Year

SCIAMACHY operations over the Christmas/New Year period will consist of nominal measurements. Operations support over the holiday period includes weekly monitoring but will be limited otherwise to urgent requests in case of anomalies. From January 9th onwards SOST will be fully operational again. Then the monitoring results will be put onto the webpages as usual.

The SCIAMACHY Operations Support Team wishes everyone involved in the SCIAMACHY mission Merry Christmas, a happy New Year and all the best for 2012.




19 December 2011: Modified January/February planning

The planning for the period January 1st - February 29th, 2012 (orbit 51453-52314) had to be modified in response to OCR 52 (increased_monitoring). This OCR requires, for monitoring the current rapid throughput recovery, additional monitoring measurements. They are implemented via a daily subsolar observation and an execution of the WLS state 61 (lwc01) in the eclipse phase of the same orbit. The WLS measurement occurs in the new timelines 61_02 and 62_02 of the timeline set 36 which are uploaded on January 9th, 2012 (orbit 51570), i.e. they define the new timeline final flight configuration FFT_120109.

The modified planning documents can be found on the SOST webpages (OSDF, SIM_SDMOP, limb_mesosphere_thermosphere, State_Summary, limb_geolocation and nadir_geolocation).




02 December 2011: January/February planning

The planning documents for the period January 1st - February 29th, 2012 (orbit 51453-52314) can be found on the SOST webpages (OSDF, SIM_SDMOP, limb_mesosphere_thermosphere, State_Summary, limb_geolocation and nadir_geolocation).

All measurements are nominal.




11 November 2011: December planning

The planning documents for the period December 1st - 31st (orbit 51008-51452) can be found on the SOST webpages (OSDF, SIM_SDMOP, limb_mesosphere_thermosphere, State_Summary, limb_geolocation and nadir_geolocation).

All measurements are nominal.




14 October 2011: ENVISAT manoeuvre and attitude mode change

On October 14th an in-plane orbit control manoeuvre is planned. It will cause a change of the platform attitude starting at 01:27 UTC (orbit 50318) with a transition from stellar yaw steering to yaw steering. At 01:29 UTC yaw steering mode is followed by the fine pointing mode. Between 03:09 UTC and 03:11 UTC the manoeuvre is executed. At 05:40 UTC the fine pointing mode changes back to yaw steering mode. Stellar yaw steering mode is accomlished at 09:53 UTC (orbit 50323).

For the entire manouevre SCIAMACHY continues the measurement plan. Therefore, due to the reduced platform attitude performance, the LoS pointing knowledge is slightly degraded.




23 September 2011: SCIAMACHY in HEATER/REFUSE mode and recovery

In orbit 50003 (September 22nd, 02:59:25 UTC) SCIAMACHY was transferred to HTR/RF mode triggered by a SDPU_Tx buffer overflow. A Single Event Upset (SEU) is considered to be the cause of the anomaly.

Since the anomaly is a known feature, recovery was started immediately. In orbit 50021 (September 23rd, 09:30:36 UTC) SCIAMACHY continued the planned measurement schedule.




09 September 2011: SCIAMACHY in HEATER/REFUSE mode and recovery

In orbit 49800 (September 8th, 00:28:14 UTC) SCIAMACHY experienced a sequence of SDP2_process_alive alarms which finally caused a PMTC mode error transferring the instrument to HTR/RF mode. Since the failure occurred when ENVISAT was right in the South Atlantic Anomaly (SAA), a Single Event Upset (SEU) is considered to be the cause of the anomaly.

This type of anomaly with exactly the same error messages has not yet occurred before. Therefore an ARB convened where it was decided to recover via STANDBY/REFUSE - STANDBY - HEATER. In orbit 49820 (September 9th, 09:42:07 UTC) SCIAMACHY continued the planned measurement schedule.




30 August 2011: October/November planning

The planning documents for the period October 1st - November 30th (orbit 50132-51007) can be found on the SOST webpages (OSDF, SIM_SDMOP, limb_mesosphere_thermosphere, State_Summary, limb_geolocation and nadir_geolocation).

All measurements are nominal.




29 August 2011: SCIAMACHY in HEATER/REFUSE mode and recovery

In orbit 49620 (August 26th, 10:12:48 UTC) SCIAMACHY was transferred to HTR/RF mode triggered by a SDPU_Tx buffer overflow. A Single Event Upset (SEU) is considered to be the cause of the anomaly.

Since the anomaly is a known feature, recovery was started immediately. In orbit 49633 (August 27th, 08:27:14 UTC) SCIAMACHY continued the planned measurement schedule.




17 July 2011: SCIAMACHY in HEATER/REFUSE mode and recovery

In orbit 49034 (July 16th, 15:45:57 UTC) SCIAMACHY was transferred to HEATER/REFUSE mode. The signature of this anomaly does not indicate an expected error such as a SDPU/PMTC buffer overflow or the CCA MCMD check error.

The current anomaly is the same as one of the first instrument anomalies which had occurred in the Commissioning Phase on April 28th, 2002 (see old news). This was confirmed at an ARB and it was decided to start immediate recovery via STANDBY mode. In orbit 49072 (July 19nd, 08:02:55 UTC) SCIAMACHY continued measurements.




12 July 2011: August/September planning

The planning documents for the period August 1st - September 30th (orbit 49255-50131) can be found on the SOST webpages (OSDF, SIM_SDMOP, limb_mesosphere_thermosphere, State_Summary, limb_geolocation and nadir_geolocation).

All measurements are nominal.




12 June 2011: June/July planning

The planning documents for the period June 24th - July 31st (orbit 48722-49254) can be found on the SOST webpages (OSDF, SIM_SDMOP, limb_mesosphere_thermosphere, State_Summary, limb_geolocation and nadir_geolocation).

All measurements are nominal.




27 May 2011: SCIAMACHY transfer to STANDBY and recovery

In orbit 48302 (May 26th, 16:48:57 UTC) SCIAMACHY was transferred in a sequence of two anomalies to STANDBY/REFUSE mode. The first anomaly was the known PMTC_Tx buffer overflow error, most likely caused by a SEU. This anomaly triggered a transfer to HTR/REF. A second failure (PMTC driver timeout) occurred immediately afterwards and sent the instrument to STANDBY mode. This anomaly is identical to the failure from March 2011.

Recovery via cold restart was started in the morning of May 27th. In orbit 48325 (May 28th, 08:08:43 UTC) SCIAMACHY continued measurements.




12 April 2011: April/May/June planning (cycles 102/103)

The planning documents for the period April 25th - June 24th (orbit 47860-48721, cycles 102 and 103) can be found on the SOST webpages (OSDF, SIM_SDMOP, limb_mesosphere_thermosphere, State_Summary, limb_geolocation and nadir_geolocation).

All measurements are nominal except on May 5th and May 10th when in orbits 47994-47999 (Venus) and 48069-48074 (Jupiter) the two brightest planets are observed as required by OCR 51 (Venus_Jupiter_2011).




04 April 2011: ENVISAT payload switch-off and recovery

In orbit 47540 (April 3rd, 15:51:36 UTC) the ENVISAT payload was switched-off due to a platform anomaly. It occurred during a planned RFI test. Recovery of the Payload Equipment Bay (PEB) and the payload instruments has started. In orbit 47567 (April 5th, 13:56:54 UTC) SCIAMACHY continued with measurements.

Because of this anomaly the SCIAMACHY limb_mesosphere_thermosphere measurements on April 4/5th, scheduled together with MIPAS operating in Upper Atmsophere mode, were not executed.




23 March 2011: SCIAMACHY transfer to STANDBY and recovery

In orbit 47370 (March 22th, 20:27:24 UTC) SCIAMACHY was transferred in a sequence of two anomalies to STANDBY/REFUSE mode. The first anomaly was the known PMTC_Tx buffer overflow error, most likely caused by a SEU. This anomaly triggered a transfer to HTR/REF. A second failure (PMTC driver timeout) occurred immediately afterwards and sent the instrument to STANDBY mode. This anomaly is identical to the failure from October 2010.

Recovery via cold restart was started in the morning of March 23rd. In orbit 47393 (March 24th, 11:17:55 UTC) SCIAMACHY continued measurements.




18 February 2011: march/April planning

The planning documents for the period March 1st - April 25th, 2011 (orbit 47057-47859) can be found on the SOST webpages (OSDF, SIM_SDMOP, limb_mesosphere_thermosphere, State_Summary, limb_geolocation and nadir_geolocation).

All measurements are nominal.




11 January 2011: New final flight configuration

From orbit 46340 (January 10th) on the final flight configuration of states has changed in response to the permanent implementation of OCR 50 (tangent_height_permanent_adjustment). This OCR adjusts the tangent heights of states with limb viewing geometry (limb 28-37 & 40/41, limb_mesosphere 27, mesosphere_thermosphere 55) by modifying the ESM Basic Scan Profile angle for the profiles no. 2, 3, 5 and 9. This achieves the specified values (see OCR_049 and OCR_050 for details).




23 December 2010: Operations support over Christmas/New Year

SCIAMACHY operations over the Christmas/New Year period will consist of nominal measurements. Operations support over the holiday period includes weekly monitoring but will be limited otherwise to urgent requests in case of anomalies. From January 10th onwards SOST will be fully operational again. Then the monitoring results will be put onto the webpages as usual.

The SCIAMACHY Operations Support Team wishes everyone involved in the SCIAMACHY mission Merry Christmas, a happy New Year and all the best for 2011.




10 December 2010: January/February planning

The planning documents for the period January 1st - February 28th, 2011 (orbit 46210-47056) can be found on the SOST webpages (OSDF, SIM_SDMOP, limb_mesosphere_thermosphere, State_Summary, limb_geolocation and nadir_geolocation).

All measurements are nominal.




22 November 2010: SCIAMACHY transition to R/W WAIT and recovery

In orbit 45619 (November 20th, 22:39:19 UTC) SCIAMACHY was transferred to R/W WAIT mode due to a CCA MCMD check error. The last occurrence of this type of anomaly was on November 4th, 2010.

Recovery was started immediately. In orbit 45641 (November 22nd, 12:35:24 UTC) SCIAMACHY continued measurements.




05 November 2010: SCIAMACHY transition to R/W WAIT and recovery

In orbit 45379 (November 4th, 05:38:09 UTC) SCIAMACHY was transferred to R/W WAIT mode due to a CCA MCMD check error. The last occurrence of this type of anomaly was on April 14th, 2010.

Recovery was started immediately. In orbit 45396 (November 5th, 11:16:38 UTC) SCIAMACHY continued measurements.




21 October 2010: October/November/December planning

The planning documents for the period October 27th - December 31st, 2010 (orbit 45261-46209) can be found on the SOST webpages (OSDF, SIM_SDMOP, limb_mesosphere_thermosphere, State_Summary, limb_geolocation and nadir_geolocation).

These planning files cover for the first time measurements in the modified ENVISAT orbit. Measurements are nominal but in the first three days after the orbit manouevre (October 27-29th) three monthly calibrations are scheduled - one each day.




12 October 2010: ENVISAT orbit manoeuvre and SCIAMACHY operations

Between October 22nd and 27th ENVISAT will be transferred from the current nominal orbit to the modified orbit for the mission extension phase which lasts at least until the end of 2013. This orbit no longer maintains the inclination at the specified value but permits drifting orbit parameters. The new time-dependent orbit parameters are listed in the table below.

Parameter Nominal Orbit Mission Extension
start extension end 2010 end 2011 end 2012 end 2013
semi-major axis (km) 7159.496 7142.146 7142.134 7142.062 7141.991 7141.919
orbital period (sec) 6035.928 6014.036 6014.022 6013.939 6013.855 6013.771
inclination (°) 98.549 98.537 98.530 98.486 98.442 98.398
MLST 22:00:00 21:59:39 22:01:38 22:06:48 22:04:41 21:55:09
repeat cycle (days) 35 30
repeat cycle (orbits) 501 431
Table: ENVISAT orbit in mission extension phase from October 2010 - end 2013.

Since the orbit altitude changes, control of SCIAMACHY's line-of-sight via the ASM and ESM scanner must be adjusted accordingly. This affects the Basic Scan Profile and Relative Scan Profile Table which have to be modified defining a new final flight configuration. In order to maintain the performance of the limb/nadir matching, each limb state must be shortened by one horizontal scan resulting in modified limb entries in the Scanner State and State Duration tables. Shortening limb states requires also updating the timelines, i.e a new timeline set 36 will become operational once SCIAMACHY measurements start in the mission extension phase. Details of the re-configuration of SCIAMACHY can be found in OCR 48 (configuring SCIAMACHY for modified orbit in mission extension).

The modified ENVISAT orbit is achieved by a sequence of thruster firings. Long burns on October 22nd and October 26th and short ones on November 2nd. From a planning point of view the extension phase starts in orbit 45222 (October 24th, 07:05:25 UTC). Between orbit 45190 (October 22nd, 01:26:25 UTC) and 45260 (October 26th, 00:14:33 UTC) SCIAMACHY remains in MEASUREMENT IDLE mode. In orbit 45261 (October 27th, 00:15:00 UTC) SCIAMACHY's on-board parameter tables will be updated while in orbit 45262 (October 27th, 01:54:47 UTC) all on-board timelines are exchanged and the routine measurement programme continues. Until November 2nd the ENVISAT platform attitude mode will be Yaw Steering Mode (YSM) instead of the nominal Stellar Yaw Steering Mode (SYSM). This could slightly degrade the line-of-sight performance. Note that the short manoeuvres on November 2nd do not impact SCIAMACHY operations.

The detailed measurement planning for the period October 27th - December 31st will be provided via the SOST website soon.




06 October 2010: SCIAMACHY transfer to STANDBY and recovery

In orbit 44953 (October 5th, 13:20:13 UTC) SCIAMACHY was transferred in a sequence of two anomalies to STANDBY/REFUSE mode. The first anomaly was the known PMTC_Tx buffer overflow error, most likely caused by a SEU. This anomaly triggered a transfer to HTR/REF. A second failure (PMTC driver timeout) occurred immediately afterwards and sent the instrument to STANDBY mode. This anomaly is identical to the failure from January 2010.

Recovery via cold restart was started immediately. In orbit 44968 (October 6th, 14:40:46 UTC) SCIAMACHY continued measurements.




26 August 2010: Short unplanned MEASUREMENT IDLE phase

Due to a ground segment anomaly the MCMDs scheduled for orbits 44364-44367 (August 25th) were not uploaded. Therefore SCIAMACHY remained in MEASUREMENT IDLE mode and no measurements were executed on August 25th between 08:35:47 UTC and 15:21:39 UTC.




24 August 2010: SCIAMACHY transition to HTR/RF and recovery

In orbit 44340 (August 23rd, 16:20:26 UTC) SCIAMACHY was transferred to HTR/RF mode triggered by a SDPU_Tx buffer overflow. A Single Event Upset (SEU) is considered to be the cause of the anomaly.

Since the anomaly is a known feature, recovery was started immediately. In orbit 44351 (August 24th, 11:12:08 UTC) SCIAMACHY continued the planned measurement schedule.




11 August 2010: New final flight configuration

From orbit 44151 (August 11th) on the final flight configuration of states has changed in response to the permanent implementation of OCR 47 (phytoplankton_permanent). This OCR shortens the integration times for clusters 16 and 18 (channel 3) for obtaining a higher spatial resolution by reducing the corresponding co-adding factors. The modification affects nadir states 6 and 7. To compensate for the higher data rate, the integration times in certain other clusters of nadir states 6 and 7 become larger, i.e. co-adding factors are increased.




10 August 2010: Transfer to HTR/RF and recovery

In orbit 44135 (August 9th, 09:13:17 UTC) SCIAMACHY was transferred to HTR/RF triggered by an I0092 parameter out-of-limit (MDI ProcAliveStatus). A Single Event Upset (SEU) is considered to be the cause of the anomaly. The last time SCIAMACHY suffered from the same anomaly was on December 18th, 2003.

After a brief ARB recovery started and the MPS schedule was resumed in orbit 44148 (August 10th, 07:43:05). Since the anomaly occurred just when the second part of OCR 44 (channel 8 anti saturation) and the permanent implementaion of modified co-adding factors in response to OCR 47 (phytoplankton permament) had been scheduled, the recovery included re-arranging the CTI table uploads required by those OCRs. In orbit 44151 both sets of CTI tables (26 for re-establishing the final flight configuration after OCR_044 measurements and 2 for permanently implementing modified co-adding factors for OCR_047) were uploaded. The corresponding eclipse t/l 53, scheduled in orbit 44150, was cancelled in order to generate the necessary measurement gap for the lengthy upload. This permitted executing the remaining measurements for OCR_044 along a subsatellite track leading over Africa - which were missed due to the anomaly - in orbits 44149 and 44150.




10 August 2010: September/October planning

The planning documents for the period September 1st - October 14th, 2010 (orbit 44460-45088) and October 15th-21st (orbit 45089-45189) can be found on the SOST webpages (OSDF, SIM_SDMOP, limb_mesosphere_thermosphere, State_Summary, limb_geolocation and nadir_geolocation).

Measurements are nominal. However due to the forthcoming ENVISAT orbit manoeuvre starting on October 22nd, 2010 the planning period is split into two Orbit Sequence Definition Files. The second OSDF covers only one week just before the manoeuvre. Thus late changes to measurement planning could be introduced without the need for modifying the planning file for the entire period. This OSDF also includes three monthly calibrations - separated by 1 day - for characterizing the status of the instrument well enough just before the manoeuvre.




14 July 2010: August planning

The planning documents for the period August 1st - 31st, 2010 (orbit 44016-44459) can be found on the SOST webpages (OSDF, SIM_SDMOP, limb_mesosphere_thermosphere, State_Summary, limb_geolocation and nadir_geolocation).

Measurements are nominal interleaved with two OCRs. One is OCR 45 (extended moon observations rerun 2010) since no conflicts with lunar occultations exist (moon rises on the dayside, i.e. no occultations can be scheduled). In addition OCR 44 (channel 8 anti saturation) is implemented. It requires modifying PETs for up to 15 states and up to 15 co-adding tables in early August for a total of 6 orbits. Because of the large number of CTI table uploads for this OCR the eclipse timelines in the orbits prior to the upload have been cancelled.




02 July 2010: Next orbit control manoeuvre

On July 06th in the early morning an out-of-plane ENVISAT manoeuvre is planned. The MPS schedule stops on July 05th at 23:50 UTC (orbit 43643) and will resume on July 06th at 07:40 UTC (orbit 43647).




17 June 2010: New final flight configuration

From orbit 43362 (June 16th) on the final flight configuration of states has changed in response to the permanent implementation of OCR 43 (improved_dark_current_pet_coadd). This OCR affects the PET settings of the 5 dark current states. It improves the coverage of PETs used for science measurements, and replaces noisy long PET settings by more accurate shorter values.




07 June 2010: July planning

The planning documents for the period July 1st - 31st, 2010 (orbit 43572-44015) can be found on the SOST webpages (OSDF, SIM_SDMOP, limb_mesosphere_thermosphere, State_Summary, limb_geolocation and nadir_geolocation).

All measurements are nominal.




26 May 2010: Platform attitude anomaly

Between orbits 43063 and 43066 (May 26th, 12:12:12 to 16:45:02 UTC) the ENVISAT platform was operated in Yaw Steering Mode (YSM) instead of the nominal Stellar Yaw Steering Mode (SYSM) due to a Star Tracker 3 malfunction. SCIAMACHY measurements continued as planned. The only minor impact could be a slightly worse attitude solution during this period.




23 April 2010: Next orbit control manoeuvre

On April 27th in the early morning an out-of-plane ENVISAT manoeuvre is planned. The MPS schedule stops on April 26th at 22:02 UTC (orbit 42640) and will resume on April 27th at 07:43 UTC (orbit 42645).




15 April 2010: SCIAMACHY transition to R/W WAIT and recovery

In orbit 42462 (April 14th, 11:46:40 UTC) SCIAMACHY was transferred to R/W WAIT mode due to a CCA MCMD check error. The last occurrence of this type of anomaly was on March 3rd, 2010.

Recovery had started immediately. In orbit 42476 (April 15th, 12:23:46 UTC) SCIAMACHY continued measurements.




12 April 2010: May/June planning

The planning documents for the period May 1st - June 30th, 2010 (orbit 42699-43571) can be found on the SOST webpages (OSDF, SIM_SDMOP, limb_mesosphere_thermosphere, State_Summary, limb_geolocation and nadir_geolocation).

All measurements are nominal.




04 March 2010: SCIAMACHY transition to R/W WAIT and recovery

In orbit 41867 (March 3rd, 22:12:27 UTC) SCIAMACHY was transferred to R/W WAIT mode due to a CCA MCMD check error. The last occurrence of this type of anomaly was on January 30th, 2010.

Recovery had started immediately. In orbit 41887 (March 5th, 08:56:39 UTC) SCIAMACHY continued measurements.




22 February 2010: Transfer to HTR/RF and recovery

In orbit 41722 (February 21st, 20:03:04 UTC) SCIAMACHY was transferred to HTR/RF triggered by an I0105 parameter out-of-limit. A Single Event Upset (SEU) is considered to be the cause of the anomaly.

The observed parameter out-of-limit is an expected error such that transition back to HEATER was started immediately. Therefore the MPS schedule could be recovered quickly in orbit 41733 (February 22nd, 14:45:52).




12 February 2010: March/April planning

The planning documents for the period March 1st - April 30th, 2010 (orbit 41826-42698) can be found on the SOST webpages (OSDF, SIM_SDMOP, limb_mesosphere_thermosphere, State_Summary, limb_geolocation and nadir_geolocation).

All measurements are nominal.




12 February 2010: Next orbit control manoeuvre

On February 16th in the early morning an out-of-plane ENVISAT manoeuvre is planned. The MPS schedule stops on February 15th at about 22:05 UTC (orbit 41638) and will resume on February 16th at about 07:00 UTC (orbit 41643).




01 February 2010: SCIAMACHY transition to R/W WAIT and recovery

In orbit 41409 (January 30th, 22:21:47 UTC) SCIAMACHY was transferred to R/W WAIT mode due to a CCA MCMD check error. The last occurrence of this type of anomaly was on November 18th, 2009.

Recovery had started immediately since the CCA MCMD check error is one of the known errors. In orbit 41430 (February 1st, 10:46:51 UTC) SCIAMACHY continued measurements.




20 January 2010: New monitoring features - scanner monitoring, detector, OBM and PMD temperature summaries

Since long-term instrument monitoring becomes more important in an extended mission, we add a few new features to our monitoring results. These include

The monitoring summaries are updated every 2-3 months.




18 January 2010: SCIAMACHY transition to STANDBY and recovery

In orbit 41186 (January 15th, 09:31:18 UTC) SCIAMACHY was transferred in a sequence of two anomalies to STANDBY/REFUSE mode. The first anomaly was the known PMTC_Tx buffer overflow error, most likely caused by a SEU. This anomaly triggered a transfer to HTR/REF. A second failure (PMTC driver timeout) occurred immediately afterwards and sent the instrument to STANDBY mode. This anomaly is identical to the two failures from June 2009.

Recovery via cold restart had started immediately. In orbit 41201 (January 16th, 10:50:52 UTC) SCIAMACHY continued measurements.




12 Jaunary 2010: Platform attitude anomaly

Between orbits 41130 and 41135 (January 11th, 11:34:56 to 19:05:37 UTC) the ENVISAT platform was operated in Yaw Steering Mode (YSM) instead of the nominal Stellar Yaw Steering Mode (SYSM) due to a Star Tracker 3 malfunction. SCIAMACHY measurements continued as planned. The only minor impact could be a slightly worse attitude solution during this period.




21 December 2009: Operations support over X-mas/New Year

SCIAMACHY operations over the X-mas/New Year period will consist of nominal measurements. Operations support over the holiday period includes weekly monitoring but will be limited otherwise to urgent requests in case of anomalies. From January 7th onwards SOST will be fully operational again. Then the monitoring results will be put onto the webpages as usual.

The SCIAMACHY Operations Support Team wishes everyone involved in the SCIAMACHY mission Merry Christmas, a happy New Year and all the best for 2010.




07 December 2009: January/February planning

The planning documents for the period January 1st - February 28th, 2010 (orbit 40981-41825) can be found on the SOST webpages (OSDF, SIM_SDMOP, limb_mesosphere_thermosphere, State_Summary, limb_geolocation and nadir_geolocation).

All measurements are nominal.




07 December 2009: Next orbit control manoeuvre

On December 8th in the early morning an out-of-plane ENVISAT manoeuvre is planned. The MPS schedule stops on December 7th at 21:52 UTC (orbit 40636) and will resume on December 8th at 07:55 UTC (orbit 40641). This implements the new rule to continue measurements even when the platform is operated in yaw steering mode (YSM) only. It might cause a slightly degraded pointing performance. About 4 orbits later ENVISAT will reach the nominal stellar yaw steering mode (SYSM).




19 November 2009: Transfer to R/W WAIT and recovery

After more than 3.5 years without having experienced the CCA MCMD check error it hit SCIAMACHY in orbit 40355 (November 18th, 08:23 UTC) again. The instrument was transferred to R/W WAIT mode. Recovery had started immediately since the CCA MCMD check error is one of the known errors.

SCIAMACHY was back to the measurement schedule in orbit 40371 (November 19th, 11:12:44 UTC).




06 October 2009: November/December planning

The planning documents for the period November 1st - December 31st (orbit 40108-40980) can be found on the SOST webpages (OSDF, SIM_SDMOP, limb_mesosphere_thermosphere, State_Summary, limb_geolocation and nadir_geolocation).

All measurements are nominal.




25 September 2009: Next orbit control manoeuvre

On September 29th in the early morning an out-of-plane ENVISAT manoeuvre is planned. The MPS schedule stops on September 28th at 22:11 UTC (orbit 39634) and will resume on September 29th at 07:49 UTC (orbit 39639). As in the previous OCM SCIAMACHY will continue measurements even when the platform is operated in yaw steering mode (YSM) only. This might cause a slightly degraded pointing performance. About 4 orbits later ENVISAT will reach the nominal stellar yaw steering mode (SYSM).




12 August 2009: SCIAMACHY transition to HTR/RF and recovery

In orbit 38911 (August 9th, 10:13:21 UTC) SCIAMACHY was transferred to HTR/RF mode. This anomaly concerned an out-of-limit (OOL) of the ASM mean motor current (I0118). Within 8 msec the ASM Control Difference (I0119) went OOL, followed 4 msec later by an OOL of the ESM overcurrent (I0121). The coincidence of OOLs of ASM and ESM parameters is pointing to a high energy particle impact in the PMTC electronics.

Since the triple OOL signature is not listed in the IOM as an expected fault, an ARB was held to discuss the recovery strategy. It was decided that the recovery shall occur according to the same procedure as described in the IOM for the expected ASM anomaly (I0111). Resuming the MPS schedule occurred in orbit 38938 (August 11th, 08:23:35 UTC).




06 August 2009: September/October planning

The planning documents for the period September 1st - October 31st (orbit 39235-40107) can be found on the SOST webpages (OSDF, SIM_SDMOP, limb_mesosphere_thermosphere, State_Summary, limb_geolocation and nadir_geolocation).

All measurements are nominal.




20 July 2009: August planning

The planning documents for the period August 1st - 31st (orbit 38791-39234) can be found on the SOST webpages (OSDF, SIM_SDMOP, limb_mesosphere_thermosphere, State_Summary, limb_geolocation and nadir_geolocation).

All measurements are nominal.




17 July 2009: Next orbit control manoeuvre

On July 21st in the early morning an out-of-plane ENVISAT manoeuvre is planned. The MPS schedule stops on July 20th at 22:00 UTC (orbit 38632) and will resume on July 21st at 07:41 UTC (orbit 38637). Contrary to previous OCMs SCIAMACHY will continue measurements even when the platform is operated in yaw steering mode (YSM) only. This might cause a slightly degraded pointing performance. About 4 orbits later ENVISAT will reach the nominal stellar yaw steering mode (SYSM).




26 June 2009: Successful Venus observation

On June 25th SCIAMACHY successfully observed Venus for a total of 5 orbits. Venus was rising in the limb TCFoV slightly after sunrise. The observation strategy included two scans over Venus, which was at the time of the measurement at a distance of 128 million km appearing under an angular diameter of about 20 arcsec. 60% of its disk was illuminated by the Sun. Although these observations were in response to a calibration related OCR ( OCR 37 - Slit width calibartion) useful scientific data about the atmosphere of Venus can be retrieved as well.




23 June 2009: SCIAMACHY transition to HTR/RF and recovery

In orbit 38216 (June 21st, 21:51:06 UTC) SCIAMACHY was again transferred to HTR/RF mode. This time it was only a single anomaly, most likely caused by a SEU.

Since the anomaly is a known feature, recovery was started immediately. In orbit 38230 (June 22nd, 21:17:00 UTC) SCIAMACHY continued the planned measurement schedule.




17 June 2009: SCIAMACHY transition to STANDBY and recovery

In orbit 38131 (June 15rd, 22:20:42 UTC) SCIAMACHY was again transferred in a sequence of two anomalies to STANDBY/REFUSE mode. The first anomaly was the known PMTC_Tx buffer overflow error, most likely caused by a SEU. This anomaly triggered a transfer to HTR/REF. A second failure (PMTC driver timeout) occurred only about 0.27 sec after transfer to HTR/REF sending the instrument to STANDBY mode. This anomaly is identical to that from June 3rd, 2009.

Immediate recovery via cold restart was started in the morning of June 16th. Measurements continued in orbit 38153 (June 17th, 12:10:55 UTC).




05 June 2009: SCIAMACHY transition to STANDBY and recovery

In orbit 37959 (June 3rd, 21:55:02 UTC) SCIAMACHY was transferred in a sequence of two anomalies to STANDBY/REFUSE mode. The first anomaly was the known PMTC_Tx buffer overflow error, most likely caused by a SEU. This anomaly triggered a transfer to HTR/REF. A second failure (PMTC driver timeout) occurred only about 0.27 sec after transfer to HTR/REF sending the instrument to STANDBY mode. This anomaly is identical to that from March 4th, 2009.

A brief ARB initiated immediate recovery via cold restart. Successful recovery was finally achieved when measurements continued in orbit 37980 (June 5th, 09:50:55 UTC).




29 April 2009: June/July planning

The planning documents for the period June 1st - July 31st (orbit 37918-38790) can be found on the SOST webpages (OSDF, SIM_SDMOP, limb_mesosphere_thermosphere, State_Summary, limb_geolocation and nadir_geolocation).

All measurements are nominal except for two cases. On June 25th in orbits 38261-38266 planet Venus is observed as required by OCR 37 (slit_width_calibration). From June 8th to July 19th planning is optimzed in support of OCR 40 (Cabauw campaign). This includes executing a nadir small swath width state exactly over Cabauw whenever possible.




06 April 2009: Orbit control manoeuvre

On April 7th in the early morning an out-of-plane ENVISAT manoeuvre is planned. The MPS schedule stops on April 6th at 23:23 UTC (orbit 37129) and will resume on April 7th at 12:32 UTC (orbit 37137).




01 April 2009: May planning

The planning documents for the period May 1st - 31st (orbit 37474-37917) can be found on the SOST webpages (OSDF, SIM_SDMOP, limb_mesosphere_thermosphere, State_Summary, limb_geolocation and nadir_geolocation).

All measurements are nominal.




01 April 2009: SOST website availability

The DLR webserver hosting the SOST website is moving from Birlinghoven to Munich next Thursday, April 9th. Re-installation of the h/w and s/w occurs until April 13th. Therefore our webpages cannot be accessed during this period. According to the current schedule the full service shall be established on Thuesday, April 14th at the latest.




20 March 2009: cL0 data availabilty 2002-2007

The monthly availability graph cL0 Data Availability information for the years 2002-2007 has been updated after verification of the products generated in a second re-consolidation run at ESRIN. In addition, all orbits where cL0 products with correct measurement data but incomplete consolidation exist have been checked as well and transferred to the SCIAMACHY cL0 master archive. Thus a final cL0 status is established for the first 5.5 years of SCIAMACHY operations. Detailed figures are given in the table below.

Year Total SCIAMACHY off OK OK / incomplete Reed Solomon Error Other Errors Missing
2002 2176 229 1712 80 39 29 87
2003 5224 447 4562 105 47 52 11
2004 5239 144 4838 118 46 69 24
2005 5225 65 4916 107 48 41 48
2006 5225 377 4679 64 19 67 19
2007 5224 181 4852 83 21 77 10
Total 28313 1443 25559 557 220 335 199
Total (%)
- all orbits
  5.1 90.3 2.0 0.8 1.2 0.7
Total (%) - available orbits     95.1 2.1 0.8 1.2 0.7
Table: SCIAMACHY consolidated level 0 statistics 2002-2007.

The year 2002 in the table above starts in orbit 2204 (August 2nd, 2002) when quasi-routine operations were scheduled for the first time. The high numbers for incompletely consolidated or missing orbits are due to the fact that until the end of 2002 specific SODAP measurements had been planned quite frequently which caused some inconsistencies in the consolidation process. However all such orbits are of no relevance for atmospheric science applications. Without taking 2002 into account almost 97% of all available orbits are covered with cL0 products.




06 March 2009: Platform attitude anomaly

Between orbits 36669 and 36681 (March 5th, 19:18:01 UTC to March 6th, 15:10:02 UTC) the ENVISAT platform was operated in Yaw Steering Mode (YSM) instead of the nominal Stellar Yaw Steering Mode (SYSM) due to a Star Tracker 3 malfunction (caused by a bright object in FoV). SCIAMACHY measurements continued as planned. The only minor impact could be a slightly worse attitude solution during this period.




06 March 2009: SCIAMACHY transition to STANDBY and recovery

In orbit 36647 (March 4th, 07:29:29 UTC) SCIAMACHY was transferred in a sequence of two anomalies to STANDBY/REFUSE mode. The first anomaly was the known PMTC_Tx buffer overflow error, most likely caused by a SEU. This anomaly triggered a transfer to HTR/REF. A second failure (PMTC driver timeout) occurred only about 0.27 sec after transfer to HTR/REF sending the instrument to STANDBY mode. This anomaly is identical to that from December 1st, 2007.

A brief ARB initiated immediate recovery via cold restart. Successful recovery was finally achieved when measurements continued in orbit 36664 (March 5th, 11:38:32 UTC).




16 February 2009: Platform attitude anomaly

Between orbits 36402 and 36422 (February 15th, 03:38:34 UTC to February 16th, 13:09:00 UTC) the ENVISAT platform was operated in Yaw Steering Mode (YSM) instead of the nominal Stellar Yaw Steering Mode (SYSM) due to a Star Tracker 3 malfunction (caused by a bright object in FoV). SCIAMACHY measurements continued as planned. The only minor impact could be a slightly worse attitude solution during this period.




12 February 2009: March/April planning

The planning documents for the period March 1st - April 30th (orbit 36601-37473) can be found on the SOST webpages (OSDF, SIM_SDMOP, limb_mesosphere_thermosphere, State_Summary, limb_geolocation and nadir_geolocation).

All measurements are nominal except on March 20th when in orbits 36873-36876 planet Venus is observed as required by OCR 37 (slit_width_calibration).




28 January 2009: Light path monitoring

SOST-IUP/IFE has updated its lightpath throughput service. It is now resident in a Linux environment. The spectral graphs are generated autonomously on a daily basis. In addition all data have been reprocessed using L1 V6 radiometric keydata. Details can be found on the instrument monitoring pages under Light Paths.




22 January 2009: Orbit control manoeuvre

On January 27th in the early morning an out-of-plane ENVISAT manoeuvre is planned. The MPS schedule stops on January 26th at 23:32 UTC (orbit 36127) and will resume on January 27th at 11:46 UTC (orbit 36135).




07 January 2009: Decontamination status

The long non-nominal decontamination in December 2008/January 2009 was executed as planned. Warmup was commanded on December 19th (orbit 35574) at 08:20 UTC and ended on January 3rd (orbit 35783) at 22:14 UT, when the cooldown phase was started. The total time with elevated temperatures was about 374 hours.

The figures below provide an overview of the detector and OBM temperature history during the decontamination (for detector temperatures only detectors 1&2 are displayed).

Fig.: Detector (1&2 - left) and OBM (right) temparture history for the decontamination with warmup starting on
December 19th and cooldown starting on January 3rd.

About 37 hr after cooldown start, SCIAMACHY was transferred to STANDBY for a period of 8.5 hr and subsequently 'recovered' back to MEASUREMENT. With this approach we intended to activate the assumed second cold trap in channels 7 & 8 which we believe is responsible for maintaining an ice free light path since the last decontamination in 2004/2005. The STANDBY mode and transfer back to HEATER/MEASUREMENT is the small gap in the figures above.




22 December 2008: Operations support over X-mas/New Year

SCIAMACHY operations over the X-mas/New Year period will consist of nominal measurements with a non-nominal decontamination (NNDEC) running in parallel. For NNDEC details see previous news. Operations support over the holiday period includes weekly monitoring but will be limited otherwise to urgent requests in case of anomalies. From January 7th onwards SOST will be fully operational again. Then the monitoring results will be put onto the webpages as usual.

The SCIAMACHY Operations Support Team wishes everyone involved in the SCIAMACHY mission Merry Christmas, a happy New Year and all the best for 2009.




19 December 2008: Decontamination started

In orbit 35574 (December 19th, 08:19 UTC), the first non-nominal decontamination since 2004/2005 (!) was started. Warm-up will last 375 hr until orbit 35797 (January 3rd, 22:13 UTC). Because of the agreed procedures (see this news), the cooldown phase will be interrupted in orbit 35820 (January 5th, 11:09 UTC) by a planned transfer to STANDBY, followed by a planned 'recovery' back to HEATER 8.5 hr later (orbit 35825, January 5th, 19:43 UTC). Measurement data are expected to be received again in orbit 35834 (January 6th, around 11:30). Detectors will be thermally stable around orbit 35860 (January 8th).

Note that the data quality will be reduced between the start of the warmup phase and the end of the extended decontamination activities including the scheduled transfer to STANDBY and back to MEASUREMENT.




12 December 2008: January/February planning

The planning documents for the period January 1st - February 28th (orbit 35757-36600) can be found on the SOST webpages (OSDF, SIM_SDMOP, limb_mesosphere_thermosphere, state_summary, limb_geolocation and nadir_geolocation).

All measurements are nominal.




17 November 2008: December planning

The planning documents for the period December 1st - 31st (orbit 35313-35756) can be found on the SOST webpages (OSDF, SIM_SDMOP, limb_mesosphere_thermosphere, state_summary, limb_geolocation and nadir_geolocation).

All measurements are nominal execpt for two periods. Until December 3rd OCR 39 (Cluster 16 and 18 short integration times) requires modifications of co-adding factors in several channels. On December 14th six orbits execute limb states only in response to the implementation of OCR 38 (full_limb_mode).




14 November 2008: Orbit control manoeuvre

On November 18th in the early morning an out-of-plane ENVISAT manoeuvre is planned. The MPS schedule stops on November 17th at 21:51 UTC (orbit 35124) and will resume on November 18th at 11:47 UTC (orbit 35133).




03 November 2008: Transfer to HTR/RF and recovery

In orbit 34894 (November 1st, 19:58:08 UTC) SCIAMACHY was transferred to HTR/RF triggered by an I0105 parameter out-of-limit. A Single Event Upset (SEU) is considered to be the cause of the anomaly.

The observed parameter out-of-limit is an expected error such that transition back to HEATER was started immediately. Therefore the MPS schedule could be recovered quickly in orbit 34906 (November 2nd, 16:18:52).




30 October 2008: Limb_Mesosphere_Thermosphere planning information

We have added a page to the SOST website listing times and orbits for the execution of the limb_mesosphere_thermosphere state. The table can be found under Limb_Mesosphere_Thermosphere.




16 October 2008: New ATC configuration

On October 15th in orbit 34643 the ATC settings were changed to account for the degradation of the ATC system. Particularly the mean ATC nadir heater power was approaching its lower limit of 1.63 W around the time of the seasonal minimum at the end of each year.

Fig.: Mean ATC heater powers per orbit since start of routine operations in August 2002. All three heater powers decrease as a sign of ATC degradation. The nadir heater decreased most and comes close to its lower limit.

The ATC adjustment raised the nadir heater power and lowered the limb heater power by about 1 W. Commanded ATC setpoints and gain factors can be found in the Thermal_History. The goal of the adjustment was to provide for stable ATC operations in the coming years and to maintain the OBM temperature as close as possible at the current value. HK telemetry readings indicate that the OBM temperature indeed remains unchanged (see figure below). The adjustment was embedded in three calibration sequences (one before, two after) in order to provide measurement data for the verification that the calibration status of SCIAMACHY has not changed.

Fig.: Orbital ATC temperature readings in orbit 34634 (before adjustment), orbit 34643 (adjustment occurred at about 5300 sec elapsed time) and orbit 34644 (after adjustment). The OBM temperature is calculated from the nadir and limb readings. OBM thermal stabilization was achieved rather quickly. Fig.: Same as left image but now for the ATC heater powers.




10 October 2008: New final flight configuration

From orbit 34922 (November 3rd) on the final flight configuration for mission scenarios, states and timelines will change in response to the permanent implementation of OCR 36 (limb_mesosphere_thermosphere). Then a limb_mesosphere_thermosphere state, which scans the upper atmosphere from 150 km down to about 60 km, becomes part of the set of 70 states. It overwrites the moon_troposphere state (ID 55). For 2 days per month, separated by about 15 days, all limb states in a timeline are replaced by the new limb_mesosphere_thermosphere state . One of these days coincides with MIPAS being operated in Upper Atmosphere mode. Permanent implementation also requires a new timeline set. Thus the current routine measurement timeline set 34 is exchanged by the new timeline set 35.




10 October 2008: November planning

The planning documents for the period November 1st - 30th (orbit 34883-35312) can be found on the SOST webpages (OSDF, SIM_SDMOP, State_Summary, limb_geolocation and nadir_geolocation).

All measurements are nominal. Note that from between November 4th onwards OCR 32 (Cluster 16 and 18 short integration times) requires modifications of co-adding factors in several channels. From November 3rd on the final flight configuration for mission scenarios, states and timelines will change in response to the permanent implementation of OCR 36 (limb_mesosphere_thermosphere). Details can be found in this news.




09 September 2008: Orbit control manoeuvre

On September 9th in the early morning an out-of-plane ENVISAT manoeuvre is planned. The MPS schedule stops on September 8th at 22:04 UTC (orbit 34123) and will resume on September 9th at 11:39 UTC (orbit 34131).

The next OCM will occur on November 18th.




24 August 2008: SCIAMACHY transition to STANDBY and recovery

In orbit 33870 (August 22nd, 06:43:54 UTC) SCIAMACHY was transferred in a sequence of two anomalies to STANDBY/REFUSE mode. The first anomaly was a SDPU_HK data timeout error, probably caused by a SEU. This anomaly triggered a transfer to HTR/REF. A second failure (STPU_Tx buffer overflow) occurred only about 0.055 sec after transfer to HTR/REF sending the instrument to STANDBY mode. The pattern of two anomalies in short succession is similar to the event occurring on December 1st.

Recovery started in the evening of the same day and MEASUREMENT TIMELINE mode was reached in orbit 33890 (August 23rd) at 16:42:10 UTC .




12 August 2008: September/October planning

The planning documents for the period September 1st - October 31st (orbit 34010-34882) can be found on the SOST webpages (OSDF, SIM_SDMOP, State_Summary, limb_geolocation and nadir_geolocation).

All measurements are nominal except for 15 orbits on September 24th and 14 orbits on October 24th when upper atmosphere states in support of OCR 36 (limb_mesosphere_thermosphere) are scheduled coinciding with MIPAS operating in Upper Atmosphere mode. During these orbits all standard limb states are replaced by the new limb_mesosphere_thermosphere state. These additional tests have been inserted to bridge the gap until a decision about permanent implementation is available.

On October 15th (orbit 34650-34652) and 16th (orbit 34664-34666) we run extra calibration & monitoring measurements because of the planned ATC adjustment on one of these days. Details about the ATC adjustment will be available around mid September.




04 July 2008: August planning

The planning documents for the period August 1st - 31st (orbit 33566-34009) can be found on the SOST webpages (OSDF, SIM_SDMOP, State_Summary, limb_geolocation and nadir_geolocation).

All measurements are nominal.




20 June 2008: SOST website modification

In the next weeks the SOST website will be modified to better handle the extended mission duration. Changes include:

  • reversing the sequence of entries in time dependent tables
  • separating time dependent information into nominal mission and mission extension
  • adding monitoring information (e.g. heater powers, scanners) and deleting obsolete content
  • applying a new webpage layout

  • This list will be implemented sequentially. Note that it is not intended to change table formats. If you notice any bugs after the modifications, please let us know.


    16 June 2008: July planning

    The planning documents for the period July 1st - 31st (orbit 33123-33565) can be found on the SOST webpages (OSDF, SIM_SDMOP, State_Summary, limb_geolocation and nadir_geolocation).

    All measurements are nominal except for 14 orbits on July 26th when testing the implementation of OCR 36 (limb_mesosphere_thermosphere) is scheduled. During these orbits all standard limb states are replaced by the new limb_mesosphere_thermosphere state. The test period has been selected such that it coincides with MIPAS operating in Upper Atmosphere mode. Upon successful execution of the test measurements it is intended to implement the limb_mesosphere_thermosphere state permanently for 30 orbits per month.




    16 June 2008: Next orbit control manoeuvre

    On July 1st in the early morning an out-of-plane ENVISAT manoeuvre is planned. The MPS schedule stops on June 30th at 22:09 UTC (orbit 33121) and will resume on July 1st at 12:42 UTC (orbit 33129).




    09 May 2008: June planning

    The planning documents for the period June 1st - 30th (orbit 32693-33122) can be found on the SOST webpages (OSDF, SIM_SDMOP, State_Summary, limb_geolocation and nadir_geolocation).

    All measurements are nominal.




    21 April 2008: Next orbit control manoeuvre

    On April 22nd in the early morning an out-of-plane ENVISAT manoeuvre is planned. The MPS schedule stops in orbit 32120 (April 21st, 23:40 UTC) and will resume in orbit 32127 (April 22nd, 12:46 UTC).




    03 April 2008: May planning

    The planning documents for the period May 1st - 31st (orbit 32250-32692) can be found on the SOST webpages (OSDF, SIM_SDMOP, State_Summary, limb_geolocation and nadir_geolocation).

    All measurements are nominal.




    14 March 2008: Platform attitude anomaly

    Between orbits 31553 and 31559 (March 13th, 09:33:46 UTC to 19:28:44 UTC) the ENVISAT platform was operated in Yaw Steering Mode (YSM) instead of the nominal Stellar Yaw Steering Mode (SYSM) due to a Star Tracker 3 malfunction (caused by a bright object in FoV). SCIAMACHY measurements continued as planned. The only minor impact could be a slightly worse attitude solution during this period.




    14 February 2008: March/April planning

    The planning documents for the period March 1st - April 30th (orbit 31376-32249) can be found on the SOST webpages (OSDF, SIM_SDMOP, State_Summary, limb_geolocation and nadir_geolocation).

    All measurements are nominal.




    11 February 2008: Next orbit control manoeuvre

    On February 12th in the early morning an out-of-plane ENVISAT manoeuvre is planned. The MPS schedule stops in orbit 31118 (February 11th, 23:40 UTC) and will resume in orbit 31125 (February 12th, 12:55 UTC).




    30 January 2008: SCIAMACHY state search engine

    We have added a tool to the SOST website permitting retrievals of states as a function of orbit number. This tool can be found under State_Search. It retrieves information on planned state executions for a specified orbit range from the State_Summary files. A detailed description is given on the State_Search page. This tool may be particularly useful when searching for calibration & monitoring states.

    The tool has been tested with the Mozilla and Internet Explorer browser. No pecularities were identified. However, since this service is a new development, bugs may still lurk around. If you spot any inconsistency please let us know. We also greatly appreciate recommendations to improve the service - as long as it can be incorporated in the SOST webpage.




    18 January 2008: ENVISAT HSM anomaly and recovery

    On January 16th in orbit 30741 (about 16:11 UTC) an anomaly of ENVISAT's High Speed Multiplexer (HSM) occurred. Since then all low rate data, including SCIAMACHY's, are either lost or corrupted.

    The recovery started January 17th at about 09:53 UTC and required a short phase in MEASUREMENT/IDLE. The same day at the end of orbit 30753 (13:14:40 UTC) SCIAMACHY was back to the MPS schedule executing the planned timelines.




    21 December 2007: Operations support over X-mas/New Year

    SCIAMACHY operations over the X-mas/New Year period will consist of nominal measurements. Operations support over the holiday period includes weekly monitoring but will be limited otherwise to urgent requests in case of anomalies. From January 7th onwards SOST will be fully operational again. Then the monitoring results will be put onto the webpages as usual.

    The SCIAMACHY Operations Support Team wishes everyone involved in the SCIAMACHY mission Merry Christmas, a happy New Year and all the best for 2008.




    17 December 2007: January/February planning

    The planning documents for the period January 1st - February 29th (orbit 30517-31375) can be found on the SOST webpages (OSDF, SIM_SDMOP, State_Summary, limb_geolocation and nadir_geolocation).

    All measurements are nominal except for 12 orbits on January 23rd/24th when measurements for the implementation of part 2 of OCR 31 (spatial straylight) are scheduled in the SO&C window.




    10 December 2007: Another service module maintenance

    The service module (SM) requires an additional reconfiguration. It is planned for December 13th. Therefore SCIAMACHY will be commanded to STANDBY mode around orbit 30249 (December 13th at 06:33:00 UTC). Transfer back to HTR shall start the same day at about 12:00 UTC with SCIAMACHY running under MPS control the next day in orbit 30264 at about 09:22 UTC.




    05 December 2007: SCIAMACHY back to MEASUREMENT

    Recovery from the recent PMTC anomaly with subsequent OCM and SM maintenance has been successfully finished in orbit 30136 (December 5th at 09:29:56 UTC). Since then SCIAMACHY executes measurements as planned in the MPS schedule.




    03 December 2007: SCIAMACHY transition to STANDBY and recovery

    In orbit 30076 (December 1st, 06:10:32 UTC) SCIAMACHY was transfered in a sequence of two anomalies to STANDBY/REFUSE mode. The first anomaly was the known PMTC_Tx buffer overflow error, most likely caused by a SEU. This anomaly triggered a transfer to HTR/REF and would have made immediate recovery possible. However unlike to previous anomalies a second failure (PMTC driver timeout) occurred only about 0.25 sec after transfer to HTR/REF sending the instrument to STANDBY mode. Since this anomaly is not characterized as expected SCIAMACHY remained in STANDBY. An ARB took place this morning and recovery, via cold restart, was initiated afterwards.

    Due to the planned OCM manoeuvre with SM maintenance, where a transition to STANDBY is already scheduled for tonight, the recovery actions are adjusted accordingly. Measurements will continue on December 5th at about 09:30 UTC.




    30 November 2007: Orbit control manoeuvre and service module maintenance

    On December 4th in the early morning an out-of-plane ENVISAT manoeuvre is planned. In addition maintenance of the service module occurs. Therefore SCIAMACHY will be transfered to STANDBY mode. The MPS schedule stops in orbit 30114 (December 3rd, 21:52 UTC) and will resume in orbit 30136 (December 5th, about 09:30 UTC). Thermal stability is reached about 1 day later.




    19 November 2007: December planning

    The planning documents for the period December 1st - 31st (orbit 30074-30516) can be found on the SOST webpages (OSDF, SIM_SDMOP, State_Summary, limb_geolocation and nadir_geolocation).

    All measurements are nominal.




    09 October 2007: November planning

    The planning documents for the period November 1st - 30th (orbit 29644-30073) can be found on the SOST webpages (OSDF, SIM_SDMOP, State_Summary, limb_geolocation and nadir_geolocation).

    All measurements are nominal (note that between November 4th - 24th OCR 32 (Cluster 16 and 18 short integration times) requires modifications of co-adding factors in several channels.




    28 September 2007: ENVISAT recovered

    ENVISAT was recovered September 26th with SCIAMACHY starting its transition to HEATER mode on September 27th at 12:30 UTC. The MPS schedule is expected to be resumed in orbit 29165 (September 28th at 13:28 UTC). Thermal stability will be achieved by tomorrow afternoon. Thus the re-planned monthly calibration on October 1st remains unaffected.




    25 September 2007: ENVISAT service module anomaly

    On September 24th in orbit 29107 (12:27:00 UTC), i.e. a few hours before the planned OCM and service module maintenance, a service module anomaly (global AOCS surveillance) occured. All payload had been switched-off. Recovery schedules are discussed. How the planned OCM and SCIAMACHY's modified monthly calibration is affected is presently unclear but will be reported here.




    21 September 2007: Orbit control manoeuvre and service module maintenance

    On September 25th in the early morning an out-of-plane ENVISAT manoeuvre is planned. In addition maintenance of the service module occurs. Therefore SCIAMACHY will be transfered to STANDBY mode. The MPS schedule stops in orbit 29112 (September 24th, 21:45 UTC) and will resume in orbit 29135 (September 26th, about 09:10 UTC). Thermal stability is reached about 1 day later.

    The planned monthly calibration in orbits 29125-29129 must be cancelled. It will be repeated on October 1st in orbits 29211-29215. The modified OSDF has already been submitted to ENVISAT Mission Planning.




    14 August 2007: SOST web support in vacation period

    Until the first week in September update of the SOST webpages will be limited. This is because of the vacation period and conference attendance. Predicted planning information covering this time interval is available however on the SIM_SDMOP site. The SOST monitoring tasks are performed as usual with monitoring status being reported via e-mail.

    All planning, operation and monitoring information acquired in the coming 2-3 weeks will be transferred to the SOST webpage as soon as the SOST team is fully operational again.




    07 August 2007: September/October planning

    The planning documents for the period September 1st - October 31st (orbit 28771-29643) can be found on the SOST webpages (OSDF, SIM_SDMOP, State_Summary, limb_geolocation and nadir_geolocation).

    All measurements are nominal except for 4 orbits on September 11th when measurements for the implementation of part 1 of OCR 31 (spatial straylight) are scheduled in the SO&C window.




    01 August 2007: SCIAMACHY recovered

    SCIAMACHY operations were recovered from yesterday's anomaly. In orbit 28318 (July 31th, 10:23:24 UTC) the MPS schedule was resumed with the execution of timeline 63.




    30 July 2007: SCIAMACHY in HTR/RF - recovery started

    In orbit 28304 (July 30th, 09:50:22 UTC) SCIAMACHY was transfered to HTR/RF due to a SDPU error. This anomaly was caused by a parameter mismatch as a result of OCR 30 (limb mesosphere/thermosphere) implementation (conflict between PET/co-adding settings and duration of horizontal limb scans). Recovery has started and it is expected that by tomorrow, July 31st, SCIAMACHY is back to the MPS schedule.

    The missed OCR_030 measurements will be repeated next week on August 8/9th (orbit 28433-28454).




    23 July 2007: Unavailability history for 2002 added

    While running the concolidated level 0 product consistency checks for the year 2002 it became obvious that a detailed listing of instrument unavailabilities similar to those generated since the start of the routine operations in 2003 was very useful. Therefore we have now added this sequence for 2002 to the corresponding page Data Unavailability History. It has to be noted that start/stop times of unavailabilities are in most cases those which were given in the unavailability reports. Since in the SODAP phase SCIAMACHY was very often in modes below MEASUREMENT/TIMELINE or timeline 63 was started manually, the duration of the unavailability intervals is often shorter than the periods defined by resuming the MPS schedule.




    12 July 2007: August planning

    The planning documents for the period August 1st - August 31st (orbit 28327-28770) can be found on the SOST webpages (OSDF, SIM_SDMOP, State_Summary, limb_geolocation and nadir_geolocation).

    All measurements are nominal.




    12 July 2007: Next orbit control manoeuvre

    On July 17th in the early morning an out-of-plane ENVISAT manoeuvre is planned. Therefore SCIAMACHY will be operated in MEASUREMENT IDLE mode from July 17th midnight to noon, i.e. data generation is suspended during this period.




    02 July 2007: SCIAMACHY recovered

    Recovery from last week's anomaly (see this news) was finished June 30th when SCIAMACHY resumed the MPS schedule in orbit 27873 at 07:27:00 UTC. A modified planning for July has been submitted to RGT to repeat the missed monthly calibration between orbits 28051-28055 (July 12th).




    29 June 2007: Transfer to HTR/RF

    In orbit 27856 (June 29th, 03:07:40 UTC) SCIAMACHY was transfered to HTR/RF. The telemetry readings indicate that the triggering fault (SDPU_Tx buffer overflow) was identical to that from the suspected SEU reported for November 23rd, 2006 (see this news).

    Recovery has already started. We expect to continue with MPS driven operations by tomorrow around 08:00 UTC. The scheduled June monthly calibration in orbits 27865-27869 will be missed. Therefore a modified OSDF is in preparation which executes a monthly calibration - without lunar measurements - around July 7/8th.




    25 June 2007: Subsolar window unobscured again

    In orbit 27779 (June 23rd) the execution of the subsolar state produced a nominal signal again. This is in line with the proposed model to explain the anomalous behaviour seen in the subsolar measurements in the past weeks (see this news). In orbit 27779 the Sun had reached an elevation which was no longer blocked by the Ka-band antenna in a parking position with azimuth = -90 deg, elevation = -9.6 deg (both in antenna coordinates). An anomaly report has been raised to specify a new antenna parking position during the critical period end of May/early of June to avoid obscuration in the coming years.




    18 June 2007: July planning

    The planning documents for the period July 1st - July 31st (orbit 27884-28326) can be found on the SOST webpages (OSDF, SIM_SDMOP, State_Summary, limb_geolocation and nadir_geolocation).

    All measurements are nominal.




    18 June 2007: Subsolar window currently obscured

    Since orbit 27436 (May 30th) the subsolar signal is corrupted. This is due to an obscuration by the Ka-band antenna. Because of the Ka-band antenna APC anomaly in September 2006 (see this news) a modified parking position had to be selected to optimize the antenna's Sun illumination. The new position seems to obscure the subsolar window just when the Sun has reached smallest zenith distance around an elevation of about -67 deg (in CFI notation), i.e. end of May/early June. It is expected that around June 23rd the Sun becomes visible again in the subsolar window. Nevertheless discussions are ongoing to change the Ka-band antenna parking position to avoid a similar effect in the coming years.




    21 May 2007: Short unplanned MEASUREMENT IDLE phase

    Due to a commanding conflict during a Svalbard pass not all of the scheduled MCMDs for May 21st were uploaded. Therefore SCIAMACHY remained in MEASUREMENT IDLE mode and no measurements were executed between orbit 27297 (02:27:35 UTC) and orbit 27299 (05:52:41 UTC).




    10 May 2007: June planning

    The planning documents for the period June 1st - June 30th (orbit 27454-27883) can be found on the SOST webpages (OSDF, SIM_SDMOP, State_Summary, limb_geolocation and nadir_geolocation).

    All measurements are nominal.




    30 March 2007: Figures of SCIAMACHY book

    Because of frequently expressed demands we have added a direct access to the figures of the SCIAMACHY book. The figures are provided via the link to the online version of the book (see this news) on the table of content page. Each chapter permits retrieving high quality figures (300 dpi in almost all cases) together with their captions including references.




    30 March 2007: Next orbit control manoeuvre

    On April 3rd in the early morning an out-of-plane ENVISAT manoeuvre is planned. Therefore SCIAMACHY will be operated in MEASUREMENT IDLE mode from orbit 26609 (April 2nd, 23:51 UTC) to 26616 (April 3rd, 12:00 UTC), i.e. data generation is suspended during this period.




    12 March 2007: April/May planning

    The planning documents for the period April 1st - May 31st (orbit 26581-27453) can be found on the SOST webpages (OSDF, SIM_SDMOP, State_Summary, limb_geolocation and nadir_geolocation).

    All measurements are nominal except for 16 orbits on April 17/18th when measurements for the implementation of OCR 29 (extra misalignment test) are scheduled in the SO&C window.




    14 February 2007: March planning

    The planning documents for the period March 1st - 31st (orbit 26137-26580) can be found on the SOST webpages (OSDF, SIM_SDMOP, State_Summary, limb_geolocation and nadir_geolocation).

    All measurements are nominal.




    06 February 2007: SCIAMACHY book online version

    The SCIAMACHY book which was published in summer 2006 (see this news) is now available via the SOST website. Please click on the book icon in the header of the webpage. This leads you to the table of content with links to each chapter.




    05 February 2007: Light path monitoring modification

    The channel averages in the SOST-IFE's monitoring webpages for the light paths have been replaced by medians. This provides better consistency between the different light paths, particularly for subsolar data in the IR.




    22 January 2007: Next orbit control manoeuvre

    On January 23rd in the early morning an out-of-plane ENVISAT manoeuvre is planned. Therefore SCIAMACHY will be operated in MEASUREMENT IDLE mode from orbit 25607 (January 22nd, 23:33:02 UTC) to 25614 (January 23rd, 12:57:01 UTC), i.e. data generation is suspended during this period.




    21 December 2006: Operations support over X-mas/New Year

    SCIAMACHY operations over the X-mas/New Year period will consist of nominal measurements. Operations support over the holiday period includes weekly monitoring but will be limited otherwise to urgent requests in case of anomalies. From January 8th onwards SOST will be fully operational again. Then the monitoring results will be put onto the webpages as usual.

    The SCIAMACHY Operations Support Team wishes everyone involved in the SCIAMACHY mission Merry Christmas, a happy New Year and all the best for 2007. Next year in March we'll start with the mission extension. Let's hope that this adds another successful phase to our mission.




    18 December 2006: ENVISAT recovered

    The ENVISAT platform and payload has been recovered. SCIAMACHY was back to MEASUREMENT mode on December 16th, 13:25:10 UTC (orbit 25071) and the first MPS driven timeline was executed December 16th, 16:38:26 UTC (orbit 25073).




    13 December 2006: ENVISAT payload switch-off

    Yesterday (December 12th, 18:02:17 UTC, orbit 25016) an anomaly occurred onboard ENVISAT which triggered a switch-off of the complete payload. Failure analysis and recovery is ongoing. Current planning expects SCIAMACHY to resume the measurement schedule in orbit 25059 on December 15th at 18:25:23 UTC.




    12 December 2006: January/February planning

    The planning documents for the period January 1st - February 28th (orbit 25293-26136) can be found on the SOST webpages (OSDF, SIM_SDMOP, State_Summary, limb_geolocation and nadir_geolocation).

    All measurements are nominal.




    24 November 2006: Planned ENVISAT payload switch-off

    Next week in orbit 24810 (November 28th, 07:37:06 UTC) SCIAMACHY will be switched-off due to ENVISAT service module maintenance. The MPS schedule will resume in orbit 24844 (November 30th, 16:40:55 UTC).




    24 November 2006: SCIAMACHY recovered

    Recovery from yesterday's anomaly (see this news) has finished today when SCIAMACHY resumed the MPS schedule in orbit 24754 at 11:01:50 UTC.




    23 November 2006: Transfer to HTR/RF

    In orbit 24740 (November 23rd, 10:13:21 UTC) SCIAMACHY was transfered to HTR/RF. The telemetry readings indicate that the triggering fault (SDPU_Tx buffer overflow) was identical to that from the suspected SEU reported for May 25th, 2006 (see this news).

    Recovery has started in the afternoon of November 23rd. We expect to continue with MPS driven operations around noon of November 24th.




    10 November 2006: December planning

    The planning documents for the period December 1st - December 30th (orbit 24849-25292) can be found on the SOST webpages (OSDF, SIM_SDMOP, State_Summary, limb_geolocation and nadir_geolocation).

    All measurements are nominal.




    12 October 2006: November planning

    The planning documents for the period November 1st - November 30th (orbit 24420-24848) can be found on the SOST webpages (OSDF, SIM_SDMOP, State_Summary, limb_geolocation and nadir_geolocation).

    All measurements are nominal but with the moon measurements of OCR 25 (extended moon observations) extending into the November lunar visibility period until orbit 24481 when occultations become possible again.




    06 October 2006: cL0 data availabilty updated

    The monthly availability graphs for the years 2003 and 2004 of the cL0 Data Availability information has been updated. They reflect now the status after ESRIN has re-generated those orbits which were identified to be incorrect or missing. This action yielded a significant number of additional cL0 products. In the next step of improving data availability, we try to find solutions for all remaining orbits where no correct cL0 product does presently exist.




    29 September 2006: ENVISAT Ka-band antenna recovery and data actisition

    Following the Ka-band antenna anomaly on September 26th (orbit 23911), ESA has decided to implement a temporary data acquisition scenario using Kiruna and the Svalbard station. This scenario allows to downlink all low bit rate data, i.e. all planned SCIAMACHY measurements. The modified acquisition setup will be operational from the evening of October 1st onwards.

    For the data of the Kiruna orbits (9 per day) NRT processing and dissemination will be as usual. For the remaining Svalbard orbits (5 per day) no immediate NRT service is planned.




    27 September 2006: ENVISAT Ka-band antenna anomaly

    Yesterday, September 26th, 12:24:55 UTC (orbit 23911) the Antenna Pointing Controller (APC) of the Ka-band antenna was switched off due to an anomaly. The APC has the task to control the antenna's movement during Ka-band communication with Artemis. Thus, as long as the Ka-band link cannot be re-established, all measurement data from orbits where ground link was scheduled to be via Artemis (at least 50% of the planned measurements) are lost. Further details will be reported here once recovery of antenna operations has progressed.




    11 September 2006: ENVISAT recovered

    The ENVISAT platform and payload has been recovered over the weekend. SCIAMACHY transfer to HEATER mode started September 10th, 17:31:00 UTC (orbit 23685) and the first MPS driven timeline was executed September 11th, 14:41:36 UTC (orbit 23697). In orbit 23717 even detectors 4 & 5 will have reached thermal stability.

    The next orbit control manouevre will be executed as announced on September 13th.




    08 September 2006: ENVISAT payload switch-off

    Yesterday (September 7th, 16:39:09 UTC, orbit 23641) an anomaly occurred onboard ENVISAT which triggered a switch-off of the complete payload. Failure analysis is ongoing. As soon as details of the recovery schedule are available they will be reported here. How the recovery may affect the planned orbit control manoeuvre is currently undefined.




    07 September 2006: Next orbit control manoeuvre

    On September 13th in the early morning an out-of-plane ENVISAT manoeuvre will be executed. Therefore SCIAMACHY will be operated in MEASUREMENT IDLE mode for a few orbits. Data generation will stop around midnight and resume in the early afternoon of this day. Detailed times of data unavailability will be reported once they are available.

    The second z-slew will be partially outside eclipse (200 sec) and will be such that the RRU may point towards the Sun for a short period.




    29 August 2006: October planning

    The planning documents for the period October 1st - October 31st (orbit 23976-24419) can be found on the SOST webpages (OSDF, SIM_SDMOP, State_Summary, limb_geolocation and nadir_geolocation).

    All measurements are nominal. Nevertheless this period still includes measurements for OCR 25 (extended moon observations) since no conflicts with lunar occultations exist (moon rises on the dayside, i.e. no occultations can be scheduled). Two more OCRs have been implemented. The first is OCR 26 (increase number of subsolar pointing measurements) which requires to exchange timeline set 33 by the new timeline set 34. In the new timeline set the subsolar pointing and fast sweep state are exchanged. The second implemented operations modification is OCR 27 (reduction of subsolar rate) which modifies the mission scenarios w.r.t. the execution of subsolar measurements. Due to the extension of the ENVISAT/SCIAMACHY mission it is necessary to reduce the number of cycles for the Nadir Calibration Window Mechanism (NCWM, = subsolar port) in order to stay within the LLI in-flight budget. In the modified scenario subsolar measurements are executed with a reduced rate of 2 per week.




    21 August 2006: September planning modified

    The planning for the period September 1st - September 30th (orbit 23546-23975) has been slightly modified in response to OCR_028 (improve limb and nadir coverage for Cabauw Dandelions-2 campaign). Modification of timeline sequences starts in orbit 23552 (September 1st) and ends in orbit 23924 (September 27th). This ensures to obtain about 25 orbits with at least fair to good Cabauw coverage within 30 days. The SOST planning webpages (OSDF, SIM_SDMOP, State_Summary, limb_geolocation and nadir_geolocation) have been updated accordingly.

    Note that all measurements for OCR 25 (extended moon observations) remained untouched.




    20 July 2006: September planning

    The planning documents for the period September 1st - September 30th (orbit 23546-23975) can be found on the SOST webpages (OSDF, SIM_SDMOP, State_Summary, limb_geolocation and nadir_geolocation).

    All measurements are nominal but it has been decided to extend the implementation of OCR 25 (extended moon observations) into the September lunar visibility period. No conflicts with lunar occultations exist since the moon rises on the dayside in September, i.e. no occultations can be scheduled.




    10 July 2006: Spectral monitoring results download

    SOST-IFE's spectral monitoring results are now available for download. Details can be found on the instrument monitoring pages under SCIAMACHY Throughput Monitoring - Download of Spectral Results.




    20 June 2006: SCIAMACHY book printed

    The book entitled SCIAMACHY, Monitoring the Changing Earth's Atmosphere is now available. It describes many aspects of the SCIAMACHY mission, including scientific requirements, instrument design, instrument operations, calibration & monitoring, algorithm development, data processing and validation. Finally SCIAMACHY's view of the Earth's atmosphere is presented.

    Fig.: SCIAMACHY book cover and imprint.

    Details of the book can be found in the imprint shown above. The publication will be distributed to the SCIAMACHY community soon. Distribution sites are DLR-OP, IUP-IFE, NIVR and ESRIN. It is also planned to provide a pdf version of the book on the web.




    12 June 2006: July/August planning

    The planning documents for the period July 1st - August 31st (orbit 22659-23545) can be found on the SOST webpages (OSDF, SIM_SDMOP, State_Summary, limb_geolocation and nadir_geolocation).

    All measurements are nominal but in orbits with moon visibility OCR 25 (extended moon observations) is implemented which executes long nominal scans when the moon is above the atmosphere. No conflicts with lunar occultations exist since the moon rises on the dayside in July/August, i.e. no occultations can be scheduled.




    29 May 2006: Transfer to HTR/RF and recovery (with update)

    In orbit 22139 (May 25th, 17:56:45 UTC) SCIAMACHY was transfered to HTR/RF. It seems to have been caused by a Single Event Upset. The telemetry readings indicate a trigger identical to that from the suspected SEUs reported for April 13th and 16th (see this news and this news).

    The recovery had been initiated with a cold re-start and measurements continued in orbit 22163 (May 27th, 09:46:20 UTC). Note that due to an anomaly in the recovery process the MPS schedule was not completely uplinked. This caused SCIAMACHY to enter MEASUREMENT/IDLE mode between orbits 22167-22172 and 22177-22181, i.e. no measurement data were generated for these periods.




    19 April 2006: SCIACHAMY recovery after April 16 anomaly

    It was decided to execute a 'cold-start' i.e. to switch SCIAMACHY off and restart. Recovery actions started April 19th, 2006 at 09:38 UTC. It is expected that measurements will continue by April 20th midday.




    16 April 2006: Transfer to HTR/RF

    In orbit 21584 (April 16th, 23:08:44 UTC) SCIAMACHY was transfered to HTR/RF. It seems to have been caused again by a Single Event Upset. The telemetry readings indicate that the trigger was identical to that from the suspected SEU reported for April 13th, 2006 (see this news).

    Presently it is decided to hold recovery actions until 19th, 2006.




    13 April 2006: Transfer to HTR/RF and recovery

    In orbit 21534 (April 13th, 10:51:38 UTC) SCIAMACHY was transfered to HTR/RF. It seems to have been caused by a Single Event Upset. The telemetry readings indicate that the trigger was identical to that from the suspected SEU reported for January 19th, 2004 (see this news).

    It was decided to do a 'warm-start' from HTR/RF to HEATER as in the January 2004 event. The recovery has been started immediately. It is expected that measurements will continue by late April 14th.




    12 April 2006: May/June planning

    The planning documents for the period May 1st - June 30th (orbit 21786-22658) can be found on the SOST webpages (OSDF, SIM_SDMOP, State_Summary, limb_geolocation and nadir_geolocation). All measurements are nominal.




    10 April 2006: ENVISAT recovered

    The ENVISAT platform and payload has been recovered over the weekend. SCIAMACHY transfer to HEATER mode started April 8th, 17:03:01 UTC (orbit 21466) and the first MPS driven timeline was executed April 9th, 14:42:35 UTC (orbit 21479). In orbit 21498 even detectors 4 & 5 had reached thermal stability. Thus the monthly calibration on April 11th (orbit 21510-21514) is expected to be executed under nominal conditions.




    06 April 2006: ENVISAT payload switch-off

    Today (April 6th, 02:09:26 UTC, orbit 21428) an anomaly occurred onboard ENVISAT which triggered a switch-off of the complete payload. The error message reads SM DSL after memory reconfiguration due to SM OBDH anomalies (SM = service module, DSL = depointing signal line, OBDH = on-board data handling). Failure analysis is ongoing. As soon as details of the recovery schedule are available they will be reported here.




    27 March 2006: Next orbit control manoeuvre

    On March 28th in the early morning an out-of-plane ENVISAT manoeuvre will be executed. Therefore SCIAMACHY will be operated in MEASUREMENT IDLE mode for a few orbits. Data generation will stop in orbit 21298 (March 28th, 00:25 UTC) and resume in orbit 21306 (March 28th, 13:49 UTC).

    This OCM has the first z-slew inside eclipse. The second z-slew will be partially outside eclipse (4 min).




    07 February 2006: March/April planning

    The planning documents for the period March 1st - April 30th (orbit 20913-21785) can be found on the SOST webpages (OSDF, SIM_SDMOP, State_Summary, limb_geolocation and nadir_geolocation). All measurements are nominal but in orbits crossing Sodankylä (Finland) between March 19th and April 15th the limb/nadir sequence of the timelines is selected such that maximum limb and nadir coverage is obtained - see OCR 24 (improve limb and nadir coverage for the Sodankylä ozone campaign).




    07 February 2006: Transfer to HTR/RF and recovery

    SCIAMACHY's unplanned unavailabilities seem to come in double packs. The recovery from the transfer to R/W WAIT in orbit 20570 had succeeded in orbit 20588 when the MPS schedule was resumed. Unfortunately in orbit 20590 (February 6th, 12:56 UTC) a transfer to HTR/RF occurred. It seems to have been caused by a Single Event Upset (at transfer start SCIAMACHY was just in the middle of the SAA). The telemetry readings indicate that the trigger was identical to that from the SEU reported for December 20th, 2003 (see this news).

    It was decided to re-inialize SCIAMACHY's ICU in order not to risk a subsequent anomaly when executing the recovery only as a 'warm-start' from HTR/RF to HEATER. The recovery has been started immediately. It is expected that measurements will continue by late February 7th.




    06 February 2006: Transfer to R/W WAIT and recovery

    After almost 9 months of operations without a single unplanned unavailability, a CCA MCMD check error had occurred in orbit 20570, (February 5th, 02:39 UTC) which triggered a transfer to R/W WAIT mode. Recovery had started immediately since the CCA MCMD check error is described in the IOM as a known error.

    The transfer to HEATER mode started in orbit 20576 and the MPS schedule was finally resumed in orbit 20588 (February 6th, 09:05 UTC).




    09 January 2006: Next orbit control manoeuvre

    On January 10th in the early morning an out-of-plane ENVISAT manoeuvre will be executed. Therefore SCIAMACHY will be operated in MEASUREMENT IDLE mode for a few orbits. Data generation will stop at shortly after midnight (January 10th, 00:54 UTC) and resume in the early afternoon of the same day (13:02 UTC).

    This OCM implements for the first time a modified strategy. Due to the decreasing tank pressure, longer OCMs are required now. Thus it is no longer possible to execute the manouevre completely in eclipse. One of the slews around the z-axis will occur partially outside eclipse. For that short phase sunlight might fall onto the SRC and RAD A. Whether this is the case depends on the orientation (clockwise or counterclockwise) of the z-slew at the beginning and end of the OCM. The OCM on January 10th executes the z-slews such that the Sun does not shine onto the radiators. In a telecon no SCIAMACHY constraints (e.g. thermal impact on radiators) have been identified for the new OCM strategy in general.




    22 December 2005: Operations support over X-mas/New Year

    SCIAMACHY operations over the X-mas/New Year period will consist of nominal measurements. Operations support over the holiday period includes weekly monitoring but will be limited otherwise to urgent requests in case of anomalies. From January 9th onwards SOST will be fully operational again. Then the monitoring results will be put onto the webpages as usual.

    The SCIAMACHY Operations Support Team wishes everyone involved in the SCIAMACHY mission Merry Christmas, a happy New Year and all the best for 2006. Let's hope that 2006 will add another successful year to our mission.




    16 December 2005: SOST websever has moved

    The SOST pages have now been moved to a new webserver. The new server address is

    http://atmos.caf.dlr.de/projects/scops

    Please update your bookmarks. An automatic re-direction from the old to the new address has been implemented. If you notice any inconsistencies using the new server, e.g. missing or broken links, please let us now.




    12 December 2005: January/February planning

    The planning documents for the period January 1st - February 28th (orbit 20068-20912) can be found on the SOST webpages (OSDF, SIM_SDMOP, State_Summary, limb_geolocation and nadir_geolocation). All measurements are nominal.




    16 November 2005: No decontamination

    Usually December/January is the time for a regular decontamination. The last decontamination in winter 2004/2005 generated very stable conditions for detectors 7 & 8 indicating that the ice was removed from the optical path. Recently it was discovered that the shape of SLS lines in channel 8 became wider and less intense. It is suggested that ice has started to grow again on the detector. However the averaged optical throughput remains rather stable. An increase observed in the average temperatures of detectors 7 & 8 may be attributed to seasonal effects.

    Perhaps an equilibrium status has now developped in channels 7 & 8 with some ice being again present. However due the the stable situation and the fact that retrievals in channel 8 are still possible it was decided at a recent ARB not to execute a decontamination. The risk to worsen things was considered too high. SLS line shape monitoring is now a regular monitoring task. Results are reported on SRON's website under Ice Effects in Channels 7 & 8. If this monitoring indicates that the growth of ice has continued the pros and cons for a further decontamination will be discussed at another ARB.




    07 November 2005: December planning

    The planning documents for the period December 1st - December 31st (orbit 19624-20067) can be found on the SOST webpages (OSDF, SIM_SDMOP, State_Summary, limb_geolocation and nadir_geolocation). All measurements are nominal except for orbits 19906-19908 (Decmeber 20th when an extra monthly calibration is inserted to account for a potential decontamination starting on December 21st.

    This planning cycle might become subject to modification since the final decision when to execute the decontamination is still pending. It depends on the exact date of the next orbit control manoeuvre which is still unknown. More details will be reported here once they are available.




    29 September 2005: November planning

    The planning documents for the period November 1st - November 30th (orbit 19195-19623) can be found on the SOST webpages (OSDF, SIM_SDMOP, State_Summary, limb_geolocation and nadir_geolocation). All measurements are nominal.




    24 August 2005: New feature - cL0 availability

    Following the discussions at the recent SSAG meetings, we decided to add our analysis of the availability of consolidated level 0 (cL0) data to the SOST website. It can be found under the bullet cL0 Data Availability at the end of the index. Although the SOST site usually deals with operations related issues only, the cL0 availability is presented here since it reflects data implementation of instrument configuration and operational planning. Thus it shall exactly match instrument operations.

    Due to properties of cL0 dissemination, the cL0 availability is always lagging behind the actual date. Late deliveries can even cause updates of rather old monthly tables. Generating the cL0 statistics is a SOST 'add-on' which has lower priority than our operations related activities. It also requires several non-autonomous data handling and analysis steps. Therefore we consider this information as best effort only.




    23 August 2005: Next orbit control manoeuvre

    On September 7th in the early morning an out-of-plane ENVISAT manoeuvre will be executed. Therefore SCIAMACHY will be operated in MEASUREMENT IDLE mode for a few orbits. Data generation will stop shortly after midnight and resume in the early afternoon of the same day. Detailed time information will be provided once available from flight dynamics.




    29 July 2005: September/October planning

    The planning documents for the period September 1st - October 31st (orbit 18322-19194) can be found on the SOST webpages (OSDF, SIM_SDMOP, State_Summary, limb_geolocation and nadir_geolocation). All measurements are nominal.




    28 July 2005: Spectral light path monitoring results

    SOST-IFE's throughput results have been extended to provide additional access to spectral information. This information is derived from level 0 data analysed in a similar way as for the channel averaged throughput data. Currently the spectral monitoring is still in a test phase. Details can be found on the instrument monitoring pages under Light Paths.




    14 June 2005: July/August planning

    The planning documents for the period July 1st - August 31st (orbit 17434-18321) can be found on the SOST webpages (OSDF, SIM_SDMOP, State_Summary, limb_geolocation and nadir_geolocation). All measurements are nominal.




    13 May 2005: Recovery started

    The recent anomaly seems to be understood now. Detailed analysis by Astrium, ESOC and us finally came to the conclusion that the transfer to R/W WAIT was in fact a Single Event Upset (SEU), disguised as a CCA MCMD check error. The anomaly occurred when ENVISAT was in the SAA. Obviously, a SEU stopped the ICU about 12 msec prior to the apparent CCA MCMD check error. The ENVISAT PMC responded with what is usually attributed to the check error.

    Transition to HEATER has started in orbit 16728 at 17:05 UTC (May 12th). We expect to resume the MPS schedule at about noon May 13th. Thermal stability in channels 1-6 will then be reached after another 25 hours.




    12 May 2005: Transfer to R/W WAIT

    In orbit 16716, (May 11th, 22:11 UTC), an anomaly had occurred which triggered a transfer to R/W WAIT mode. There are indications that the anomaly is the well known CCA MCMD check error. The last anomaly of this kind dates back to October 2004. However, since dump analysis is not yet fully conclusive, an ARB will be held before recovery can start. Details on the recovery will be provided here as soon as they are available.




    10 May 2005: Back in MEASUREMENT

    In a very fast recovery ESOC transferred SCIAMACHY back to MEASUREMENT mode. The first timeline was run yesterday evening May 9th at 18:37 UTC (orbit 16686). The MPS schedule was then resumed at 19:01 UTC with timeline 52.




    09 May 2005: June planning

    The planning documents for the period June 1st - June 30th (orbit 17005-17433) can be found on the SOST webpages (OSDF, SIM_SDMOP, State_Summary, limb_geolocation and nadir_geolocation). All measurements are nominal but in orbits crossing Cabauw (The Netherlands) the limb/nadir sequence of the timelines is selected such that maximum nadir coverage is obtained - see OCR 23 (improve nadir coverage for the Cabauw campaign).




    09 May 2005: Transfer to HTR/RF and recovery

    After almost 6 months of instrument operations without a severe anomaly, SCIAMACHY was transferred to HTR/RF triggered by an I0105 parameter out-of-limit (orbit 16675, May 9th, 00:25 UTC). A Single Event Upset (SEU) is considered to be the cause of the anomaly.

    The observed parameter out-of-limit is an expected error such that recovery with transition back to HEATER had started immediately at about 02:00 UTC (orbit 16676). Tomorrow morning (May 10th), SCIAMACHY will pick up the MPS schedule again with thermal stability of detectors 1-6 being accomplished in the evening of the same day.




    08 April 2005: Instrument availability display added in operations summary

    In Operations Summary a new display is added to show the status of the instrument since launch. This availability graph is intended to supplement the monthly operations summaries. Information for the very early mission phases has been assembled from historical data. If you detect any inconsistencies, please let us know.




    04 April 2005: May planning

    The planning documents for the period May 1st - May 31st (orbit 16561-17004) can be found on the SOST webpages (OSDF, SIM_SDMOP, State_Summary, limb_geolocation and nadir_geolocation). All measurements are nominal but in orbits crossing Cabauw (The Netherlands) the limb/nadir sequence of the timelines is selected such that maximum nadir coverage is obtained - see OCR 23 (improve nadir coverage for the Cabauw campaign).




    10 March 2005: Next orbit control manoeuvre

    On March 17th in the early morning an out-of-plane ENVISAT manoeuvre will be executed. Therefore SCIAMACHY will be operated in MEASUREMENT IDLE mode for a few orbits. Data generation will stop shortly after midnight and resume in the early afternoon of the same day. Detailed time information will be provided once available from flight dynamics.




    18 February 2005: March to April planning

    The planning documents for the period March 15th - April 30th (orbit 15888-16560) can be found on the SOST webpages (OSDF, SIM_SDMOP, State_Summary, limb_geolocation and nadir_geolocation). All measurements are nominal.




    24 January 2005: February to March planning

    The planning documents for the period February 15th - March 14th (orbit 15487-15887) can be found on the SOST webpages (OSDF, SIM_SDMOP, State_Summary, limb_geolocation and nadir_geolocation). All measurements are nominal. Note that during the TROCCINOX-2 campaign until February 23rd, the limb vertical step height in limb state 32 is reduced by a factor of 2 - see this news.




    20 January 2005: Modified limb state 32 during TROCCINOX-2 campaign

    Between January 29th and February 23rd (orbit 15244-15603), the limb state with ID 32 will be executed with a reduced vertical step height of 1.6 km. This is in response to OCR 22 (vertical sampling of 1.6 km during TROCCINOX-2 campaign). Limb state 32 will be scheduled between geographic latitudes 30° and -60°, i.e. the required vertical sampling is ensured at the campaign site in Brazil. All other limb states maintain the step width of 3.3 km.




    10 January 2005: Decontamination status

    The long non-nominal decontamination in December 2004/January 2005 was executed as planned. Warmup was commanded on December 20th (orbit 14675) at 08:05 UTC and ended on January 2nd (orbit 14860) at 06:16 UT, when the cooldown phase was started. The total time with elevated temperatures was about 310 hours.

    The figures below provide an overview of the detector and OBM temperature history during the decontamination (for detector temperatures only detectors 1&2 are displayed).

    Fig.: Detector (1&2 - left) and OBM (right) temparture history for the decontamination with warmup starting on
    December 20th and cooldown starting on January 2nd.

    About 37 hr after cooldown start, SCIAMACHY was transferred to STANDBY for a period of 8.5 hr and subsequently 'recovered' back to MEASUREMENT. This planned procedure resembled last years 'winter' decontamination when the ice in detectors 7 & 8 was largely removed from the light path. The STANDBY mode and transfer back to HEATER/MEASUREMENT is the first gap in the figure above. The second gap is caused by the ENVISAT orbit control manoeuvre (OCM), which occurred between orbits 14930 and 14936 (January 7th, 02:30-13:43 UTC). During the OCM; SCIAMACHY was commanded to MEASUREMENT IDLE and the MPS schedule was suspended.




    23 December 2004: Operations support over X-mas/New Year

    SCIAMACHY operations over the X-mas/New Year period will consist of the non-nominal decontamination, including the extra mode transitions in the cooldown, and the execution of nominal measurements. Operations support over the holiday period will be limited to urgent requests in case of anomalies. From January 10th onwards SOST will be fully operational again.

    The SCIAMACHY Operations Support Team wishes everyone involved in the SCIAMACHY mission Merry Christmas, a happy New Year and all the best for 2005. Let's hope that 2005 will add another successful year to our mission.




    21 December 2004: Next orbit control manoeuvre

    On January 7th, around 05:00 UTC, an out-of-plane ENVISAT manoeuvre will be executed. Therefore SCIAMACHY will be operated in MEASUREMENT IDLE mode for a few orbits. Data generation will stop around 02:00 UTC and resume in the early afternoon of the same day.




    21 December 2004: Decontamination started

    In orbit 14675 (December 20th, 08:05 UTC), the next non-nominal decontamination was started. Warm-up will last 310 hr until orbit 14860 (January 2nd, 06:16 UTC). This is shorter than originally planned but takes into account ENVISAT's next orbit manoeuvre (see this news). Because of the agreed procedures (see this news), the cooldown phase will be interrupted in orbit 14882 (January 3rd, 19:10 UTC) by a planned transfer to STANDBY, followed by a planned 'recovery' back to HEATER 8.5 hr later (orbit 14887, January 4th, 03:40 UTC). Measurement data are expected to be received again in orbit 14898 the same day. Detectors will be thermally stable around orbit 14916 (January 6th).

    Note that the data quality will be reduced between the start of the warmup phase and the end of the extended decontamination activities including the scheduled transfer to STANDBY and back to MEASUREMENT.




    12 December 2004: January to February planning

    The planning documents for the period January 15th - February 14th (orbit 15044-15486) can be found on the SOST webpages (OSDF, SIM_SDMOP, State_Summary, limb_geolocation and nadir_geolocation). All measurements are nominal.




    25 November 2004: December to January planning

    The planning documents for the period December 15th - January 14th (orbit 14600-15043) can be found on the SOST webpages (OSDF, SIM_SDMOP, State_Summary, limb_geolocation and nadir_geolocation). January 12th (orbit 15002-15015) measurements with small swath width in response to OCR 13 (check of vertical azimuth alignement in limb states) are planned. All other measurements are nominal. The monthly calibration occurs December 16th without observing the moon. This is to avoid an impact of the next decontamination, which is planned to start around December 20th, on calibration & monitoring data .

    Note that the data quality will be reduced between the start of the warmup phase and the end of the decontamination activities which will be of extended duration because of the scheduled transfer to STANDBY and back to MEASUREMENT (see this news).




    24 November 2004: Reference time information added

    We have added the time difference between reference orbit and predicted orbit as text files in the section Time_Reference. This facilitates the retrieval of the associated information for data analysis purposes.




    17 November 2004: Transfer to HTR/RF and recovery

    SCIAMACHY was transferred to HTR/RF triggered by an I0105 parameter out-of-limit (orbit 14198, November 17th, 00:10 UTC). This parameter represents the combined digital status monitoring - Event Control warning W1 - where the affected individual parameter reads Latch-Up Detection Thermal 2 Board. The transfer occurred while the instrument was executing Nadir state ID 01. ENVISAT's orbit position coincided with the southern part of the SAA (approx. -65° south, -20° west). Thus a Single Event Upset (SEU) is considered to be the cause of the anomaly.

    Recovery has started the same day 322 already in orbit 14206 with the transition to HEATER mode at 12:40:26 UTC. It is expected that tomorrow, in orbit 14216, SCIAMACHY will pick up the MPS schedule again. Thermal stability will be accomplished in orbit 14229 (detectors 1-6) and 14238 (detectors 7 & 8).




    11 November 2004: Next decontamination

    The next non-nominal decontamination is planned for end of December 2004/beginning of January 2005. The warm-up phase will start around December 20th and the cool-down will end the period with elevated temperatures January 5th. The total warm-up phase will last 375 hr.

    Because the decontamination one year ago provided very good results w.r.t. the detector 7 & 8 throughput and it is speculated that this was caused by the extra cooling due to the transfer to R/W WAIT during the cooldown phase (triggered by a CCA MCMD check error), it has been decided to mimic this event by intentionally transfer SCIAMACHY to STANDBY about 37 hr after the start of the cooldown on January 5th. The instrument will stay in STANDBY mode for about 8.5 hr and then commanded back to HEATER mode. Nominal thermal conditions are expected January 9th.




    21 October 2004: November to December planning

    The planning documents for the period November 15th - December 14th (orbit 14171-14599) can be found on the SOST webpages (OSDF, SIM_SDMOP, State_Summary, limb_geolocation and nadir_geolocation). All measurements are nominal.




    15 October 2004: Full Mozilla access to geolocation information restored

    A workaround has been installed at the local firewall to restore ftp downloads via the Mozilla browser from the geolocation pages of our website. This service is now fully operational again.




    08 October 2004: Limited access to geolocation information

    A new firewall has been installed at our facilities. Unfortunately this firewall is unable to provide ftp-access via the Mozilla browser. This affects the geolocation information on our webiste (state_summary, limb_geolocation and nadir_geolocation). It is therefore recommended, to use Internet Explorer or Netscape for the time being if a user wants to view or download files from these areas.

    As soon as Mozilla access is fully operational again, we will report it here.




    04 October 2004: Transfer to R/W WAIT and recovery

    In orbit 13526, (October 1st, 00:24 UTC), a CCA MCMD check error had occurred which triggered a transfer to R/W WAIT mode. This is the third error of this kind in 2004, i.e. the frequency is still compliant with the estimate of 2-3/year. Recovery had started immediately since the CCA MCMD check error is described in the IOM as a known error.

    The transfer to HEATER mode started in orbit 13533 (October 1st at 12:16 UTC and the MPS schedule was finally resumed in orbit 13546 (October 2nd, 11:05 UTC). Detectors 1-6 reached stable temperatures in orbit 13559 (October 3rd, at about 08:00 UTC) while detectors 7 & 8 required about 16 hours more time to stabilize.




    27 September 2004: October to November planning

    The planning documents for the period October 15th - November 14th (orbit 13727-14170) can be found on the SOST webpages (OSDF, SIM_SDMOP, State_Summary, limb_geolocation and nadir_geolocation). All measurements are nominal.




    27 September 2004: Back in MEASUREMENT

    The recovery of the recent SEU anomaly, which had transferred SCIAMACHY to HTR/RF mode, was finished in orbit 13430 (September 24th) when the MPS schedule was resumed at 08:34 UTC.




    23 September 2004: Transfer to HTR/RF and recovery

    SCIAMACHY was transferred to HTR/RF triggered by an I0121 parameter out-of-limit (orbit 13410, September 22nd, 22:59 UTC). This parameter represents the ESM overcurrent. The transfer occurred while the instrument was in IDLE between a nadir state and the ADC calibration state, i.e. no scanners were operating. ENVISAT's orbit position coincided with the southern part of the SAA. Thus a Single Event Upset (SEU) is considered to be the cause of the anomaly.

    Recovery has started on Thursday already in orbit 13416 with the transition to HEATER mode at 08:07:45 UTC. It is expected that tomorrow, in orbit 13430, SCIAMACHY will pick up the MPS schedule again. Thermal stability will be accomplished in orbit 13443 (detectors 1-6) and 13452 (detectors 7 & 8).




    15 September 2004: Next orbit control manoeuvre

    On September 21st, an out-of-plane ENVISAT manoeuvre will be executed. Therefore SCIAMACHY will be operated in MEASUREMENT IDLE mode for a few orbits. Data generation will stop in orbit 13384 at 02:17 UTC and resume in orbit 13393 at 18:32 UTC.




    13 September 2004: Manoeuvre information

    In orbit 13110 (September 1st, 23:52 UTC) an emergency collission avoidance manoeuvre was executed triggered by a 'high risk conjunction event prediction' for the next day for a Russian Cosmos satellite. In order to restore ENVISAT's orbit, a second manoeuvre occurred in orbit 13125 (September 3rd, 00:44 UTC). Both activities were in-plane manoeuvres, i.e. SCIAMACHY remained 'on'. The data quality in the aforementioned period might be degraded w.r.t. pointing information.

    For September 21st, an out-of-plane ENVISAT manoeuvre is planned requiring SCIAMACHY to be operated in MEASUREMENT IDLE mode for a few orbits. Detailed schedule information will be reported here as soon it is available.




    03 August 2004: August to October planning

    The planning documents for the period August 25th - October 14th (orbit 12997-13726) can be found on the SOST webpages (OSDF, SIM_SDMOP and Geolocation). This period is 'OCR high season'. It includes the test measurements of OCR 18 (checkout of modified CTI conversion of timelines on September 14th, orbit 13290). From a scientific point of view much more interesting is the implementation of OCR 17 (modification of nadir states at high northern and southern latitudes to improve SNR, upload of the required new timeline set 33 for routine operations occurs on September 6 th, orbit 13172) and OCR 19 (execution of limb_mesosphere states only in eclipse, occurs with the upload of the new timeline set 33). All other measurements are nominal.




    06 July 2004: SCIAMACHY back to measurement

    Shortly after yesterday's CCA MCMD check error, recovery back to measurement was initiated. The transfer to HEATER mode started at 13:25 UTC and today in orbit 12286 (July 6th, 10:22 UTC) the MPS schedule was resumed. We expect that detectors 1-6 will reach stable temperatures tomorrow, July 7th, at about 13:30 UTC. Detectors 7 & 8 require about 16 hours more time to stabilize.




    05 July 2004: Transfer to R/W WAIT mode

    In orbit 12269, (July 5th, 05:52 UTC), a CCA MCMD check error has occurred and has sent us to R/W WAIT. SCIAMACHY had the last error of this kind 6 months ago in January 2004, i.e. the frequency is compliant with the estimate of 2-3/year. Recovery has started. Further details will be reported here as soon as they are available.




    02 July 2004: Decontamination status

    The long non-nominal decontamination ended on June 28th (orbit 12174) at 14:32 UT, when the cooldown phase was started. The total time with elevated temperatures was about 240 hours.

    The figures below provide an overview of the detector and OBM temperature history during the decontamination (for detector temperatures only detectors 1&2 are displayed).

    Fig.: Detector (1&2 - left) and OBM (right) temparture history for the decontamination with effective warmup starting
    on June 18th and cooldown starting on June 28th.



    30 June 2004: July/August planning

    The planning documents for the period July 23rd - August 24th (orbit 12524-12996) can be found on the SOST webpages (OSDF, SIM_SDMOP and Geolocation). This interval includes the test measurements of OCR 17 (checkout of modified timelines on July 23rd/24th, orbits 12525-12552). August 10th (orbit 12782-12795) measurements with small swath width in response to OCR 13 (check of vertical azimuth alignement in limb states) are planned. All other measurements are nominal.




    22 June 2004: Attitude anomaly

    Between orbits 12070 (June 21st, 07:56:33 UTC) and 12087 (June 22nd, 11:50:18 UTC) ENVISAT was operated in Yaw Steering mode (YSM) instead of the nominal Stellar Yaw Steering mode (SYSM), after an anomaly had occurred in star tracker commanding. YSM has a reduced Earth pointing performance compared to SYSM, i.e. data obtained in that period can be of reduced quality.




    18 June 2004: Decontamination starts today

    In Orbit 12031 (June 18th, 14:46 UTC), the warm-up phase of a long non-nominal decontamination will be started. The warm-up phase will last 240 hrs. On June 28th (orbit 12174) warm-up will be terminated and after approx. 48 hrs detectors 1-6 will have established nominal temperatures again (56 hrs for detectors 7/8). From orbit 12203 (detectors 1-6) and 12208 (detectors 7&8) onwards measurement data are expected to be of nominal quality.




    17 May 2004: June/July planning

    The planning documents for the period June 23rd - July 22nd (orbit 12095-12523) can be found on the SOST webpages (OSDF, SIM_SDMOP and Geolocation). All measurements are nominal.




    17 May 2004: Next decontamination

    The next non-nominal decontamination is planned for the second half of June. The warm-up phase will start in the afternoon of June 18th and the cool-down will end the period with elevated temperatures June 28th. The total warm-up phase will last 240 hr, i.e. it is about 30 hr shorter than in the non-nominal decontamination of December 2003. Nominal thermal conditions are expected July 1st when the July monthly calibration is scheduled and the ICARRT validation campaign will start.




    10 May 2004: Transfer to HTR/RF and recovery

    After almost 4 months of uninterrupted nominal operations, SCIAMACHY was transferred to HTR/RF triggered by an I6275 parameter out-of-limit (orbit 11449, May 8th, 21:52 UTC). This parameter checks the high data rate status of the instrument. The transfer occurred while executing the long Sun occultation state 49. The cause of the anomaly is a suspected Single Event Upset (SEU).

    Recovery has started on Sunday already. In orbit 11471 (May 10th), SCIAMACHY picked-up the MPS schedule again. Because transfer to HTR mode was initiated very quickly, thermal stability will be accomplished in orbit 11482 (detectors 1-6) and 11491 (detectors 7 & 8).




    26 April 2004: May/June planning

    The planning documents for the period May 22nd - June 22nd (orbit 11637-12094) can be found on the SOST webpages (OSDF, SIM_SDMOP and Geolocation). This interval includes the Venus tranist measurements of OCR 16 (observation of Venus transit on June 8th, orbits 11880-11889). At the beginning of the planning interval in orbit 11638, the complete nominal timeline set 31 (FFT_031015) is replaced by timeline set 32 (FFT_040522) in response to OCR 12 (improvement of limb/nadir matching in early orbit phase). All other measurements are nominal.




    06 April 2004: Measurement interrupt due to orbit control manoeuvre

    On April 14th, an ENVISAT out-of-plane orbit control manoeuvre (OCM) will be performed. Therefore SCIAMACHY has to be commanded to MEASUREMENT IDLE mode for a few orbits, i.e. the planned timelines will not run. According to current planning this will occur between orbit 11094 and 11100 (about 02:44-13:55 UTC).




    30 March 2004: Operations summary added to website

    We have added a SCIAMACHY operations summary to the SOST website. The graphic displays list the fractions of each major operations class (e.g. nominal, nndec, anomalies) for each month on a yearly basis. The summary can be found under Operations Summary in the Instrument Monitoring section.




    24 March 2004: April/May planning

    The planning documents for the period April 15th - May 22nd (orbit 11107-11636) can be found on the SOST webpages (OSDF, SIM_SDMOP and Geolocation). This interval includes the test measurements of OCR 12 (improvement of limb/nadir matching in early orbit phase, orbits 11108-11135) and 16 (Venus transit, orbit 11168/11169 & 11171/11172). All other measurements are nominal.




    24 March 2004: Detector 7 & 8 temperature monitoring enabled

    Since the temperature drifts of detectors 7 & 8 are becoming smaller, it has been decided to include now both detectors in the weekly operational temperature monitoring. The drift of detector 8 of approx. 2 mK/orbit and the allowed temperature range of detector 8 of 1 K requires to adjust the trim heater DAC1 on a more or less regular timescale of several weeks. For the first time this will occur April 1st. How to implement the operational procedure for succeeding adjustments is still under discussion. Details will be reported here.




    11 March 2004: Limb with higher vertical sampling

    In orbits 10767-10783 (March 22nd/23rd) and orbits 10797-10810 (March 24th/25th) the limb measurements will be executed with a higher vertical sampling in response to OCR 14. Instead of the nominal 3 km, the vertical limb steps will be reduced to 1.5 km (number of steps is maintained). During the first period the start altitude will in addition be lifted from -3 km to about 10 km while in the second period start altitude remains at -3 km.




    11 March 2004: Trim heater adjustment

    Next Tuesday, March 16th, the trim heaters will be adjusted to bring detectors 5 and 8 back to the temperature limits. Adjustment will cause a short thermal instability. Actual adjustment time, trim heater values and thermal instability period will be reported on the SOST website.




    20 February 2004: March/April planning cycle

    The planning documents for the period March 15th - April 15th (orbit 10664-11106) can be found on the SOST webpages (OSDF, SIM_SDMOP and Geolocation). Only nominal measurements are executed within that time interval.




    03 February 2004: Measurement interrupt

    Tomorrow, February 4th, an ENVISAT out-of-plane orbit control manoeuvre (OCM) will be executed. Therefore SCIAMACHY has to be commanded to MEASUREMENT IDLE mode in the period orbit 10092-10098 (02:29-13:47 UTC), i.e. the planned timelines will not run. During orbit 10098 the MPS schedule will be resumed. It is expected that the monthly calibrations starting in orbit 10101 will not be affected by unstable pointing. According to specifications, pointing shall be nominal shortly after re-establishing stellar yaw steering mode at the end of orbit 10097.




    29 January 2004: Next planning cycle

    The planning documents for the period February 15th - March 15th (orbit 10248-10663) can be found on the SOST webpages (OSDF, SIM_SDMOP and Geolocation). Only nominal measurements are executed within that time interval.




    21 January 2004: Return to operations

    At the beginning of orbit 9883 (January 20th, 12:34 UTC) SCIAMACHY finally reached MEASUREMENT mode and is now back under MPS control executing the scheduled timelines. Thermally stable detector conditions will be achieved at about 16:00 UTC, January 21 st.




    20 January 2004: Transfer to HTR/RF and recovery

    In orbit 9867, (January 19th, 09:52 UTC), SCIAMACHY was transfered to HTR/RF, caused by an SDPU_Tx_Buffer overflow. This error is similar to the one from December 20th. However ENVISAT was not in the SAA or polar belts when the anomaly occurred, but over central Europe. Therefore the probability for a spurious event is small although an SEU cannot be ruled out. Investigations are ongoing.

    Nevertheless an ARB has decided to re-start SCIAMACHY by directly going from HTR/RF to HEATER mode ('warm restart'). The transfer was commanded in the afternoon of January 19th such that it can be expected to resume MPS driven operations within about 1 day. We will report here when this has been achieved.




    07 January 2004: Decontamination status

    The long non-nominal decontamination ended on January 3rd (orbit 9644) at 20:53 UT, when the cooldown phase was started. The planned total warmup time for this decontamination should have been 375 hr but due to the two SEU anomalies, switching-on the effective warmup phase was delayed until December 23 rd at 12:17 UT in orbit 9482. Thus the total time with elevated temperatures was about 270 hours.

    The figures below provide an overview of the detector and OBM temperature history during the decontamination (for detector temperatures only detectors 1&2 are displayed). The features on the left side are the two aborted decontaminations as a result of the SEUs and subsequent recoveries.

    Fig.: Detector (1&2 - left) and OBM (right) temparture history for the decontamination with effective warmup starting
    on December 23th and cooldown starting on January 3rd.



    07 January 2004: Transfer to R/W WAIT mode and recovery

    In orbit 9667, (January 5th, 10:19 UTC), another 'unforced' anomaly occurred and sent us to R/W WAIT. This was the well known CCA MCMD check error. SCIAMACHY had the last error of this kind last year in February such that the frequency is compliant with the estimate of 2-3/year. Since the CCA check error is classified in the IOM as 'expected', recovery was started at ESOC immediately. In orbit 9685, (January 6th, 16:23 UTC), SCIAMACHY recovery was completed when the MPS schedule was resumed.

    The transfer to R/W WAIT did not impact the decontamination because the associated cooldown had already brought the temperatures back to nominal levels. However, the January monthly calibration was started in orbit 9686, i.e. without having achieved full thermal stability. Whether or not to repeat the monthly calibration will be decided soon.




    23 December 2003: Operations support over X-mas/New Year

    SCIAMACHY operations over the X-mas/New Year period will consist of the non-nominal decontamination (start of cooldown occurs in orbit 9644, January 3rd) and the execution of nominal measurements. Operations support over the holiday period will be limited to urgent requests in case of anomalies. From January 7th onwards SOST will be fully operational again.

    The SCIAMACHY Operations Support Team wishes everyone involved in the SCIAMACHY mission Merry Christmas, a happy New Year and all the best for 2004. Let's hope that 2004 will add another successful year to our mission.




    23 December 2003: SCIAMACHY back to measurement

    At the end of orbit 9482 (December 23rd, 13:18 UT) SCIAMACHY finally reached MEASUREMENT mode and is now back under MPS control executing the scheduled timelines. All subsystems look nominal. Decontamination has started December 23 rd, 12:17 UT. Because the start of the cool-down cannot be shifted backwards, the overall duration of the warm-up phase is reduced to about 270 hr.




    22 December 2003: Recovery and a second HTR/RF

    The recovery from the transfer to HTR/RF in orbit 9412 had succeeded in orbit 9426 (December 19th, 15:24 UTC) when the MPS schedule was picked up again. Since then SCIAMACHY operated nominally in MEASUREMENT mode while the decontamination was running.

    Unfortunately in orbit 9439 (December 20th, 12:34 UT) another transfer to HTR/RF occurred. Again it seems to be caused by a Single Event Upset (at transfer start SCIAMACHY was just in the middle of the SAA executing a standard nadir state). The telemetry available indicates that this SEU is unrelated to the one of last Thursday. It was decided to re-inialize SCIAMACHY's ICU in order not to risk a subsequent anomaly when executing the recovery only as a 'warm-start' from HTR/RF to HEATER. The recovery has been started December 22nd. It is expected that measurements will continue by late December 23rd/early December 24th.

    The current decontamination has to be terminated in preparation of the recovery. A new non-nominal decontamination will be started as soon SCIAMACHY has reached HEATER mode. The associated warm-up phase will be of significantly shorter duration since the start of the cool-down cannot be shifted backwards. Expected duration of the warm-up phase is in the order of 240 hr.




    19 December 2003: Transfer to HTR/RF and recovery

    In orbit 9412, (December 18th, 15:41 UTC), SCIAMACHY was transfered to HTR/RF. The most likely cause of this event is a Single Event Upset (SEU), triggered when ENVISAT was crossing the Antarctic region. ESOC immediately initiated transfer back to HEATER mode in the evening of the same day. We will report here when SCIAMACHY will have resumed the MPS schedule.

    The transfer to HTR/RF impacted the running non-nominal decontamination in the same way as in the mid August event, i.e. decontamination heaters stayed 'on' and only ATC/TC heaters were 'off' for the duration of the HTR/RF phase. Thus no significant reduction of the warm-up phase duration is expected. The decontamination continues as described in the previous news.




    18 December 2003: Decontamination started

    In Orbit 9407 (December 18th), the warm-up phase of a long non-nominal decontamination was started. The warm-up phase will last 375 hrs. On January 3rd (orbit 9644) warm-up will be terminated and after approx. 48 hrs detectors 1-6 will have established nominal temperatures again (56 hrs for detectors 7/8). From orbit 9673 (detectors 1-6) and 9678 (detectors 7/8) onwards measurement data are expected to be of nominal quality.




    08 December 2003: ENVISAT attitude mode

    In the course of testing new s/w to improve state vector uploads, the attitude mode of the ENVISAT platform will be changed from Stellar Yaw Steering Mode (SYSM) - which is the operations baseline - to Yaw Steering Mode (YSM) for the duration of the test. According to ESA's announcement, YSM will be running from December 9th to December 10th. While operating in YSM, a reduced pointing performance can occur.




    08 December 2003: SCIAMACHY back to operations

    The recovery of SCIAMACHY was successfully completed in orbit 9239 (December 6th, 12:37 UT), when the MPS schedule was resumed. Analysis of the HK telemetry indicates that the December monthly calibration (orbits 9256-9260) was executed in fairly stable thermal conditions and does not require replanning.

    Note that the modified TC settings to adjust the temperatures of detectors 4 & 5 have already been uploaded in the recovery process. Thus both detector temperatures are now again well within the temperature limits.




    05 December 2003: SCIAMACHY recovery in progress

    The recovery of SCIAMACHY after the ENVISAT PLSOL is proceeding. The recovery has been delayed a bit since the transition to HEATER had to be repeated due to an interrupt in the processing of the SCIAMACHY specific command queue. Present planning expects to continue with MPS driven measurements in the evening of December 6th. Whether or not to achieve stable temperatures for the December monthly calibration on Sunday, December 7th, is presently unclear. If telemetry analysis next Monday will indicate an unstable thermal environment while running the calibration, it is intended to replan the monthly calibration as quick as possible.




    03 December 2003: ENVISAT payload switch-off

    In orbit 9193, 07:18:43 UTC (December 3rd), an anomaly occurred onboard ENVISAT which triggered a switch-off of the complete payload. Failure analysis is ongoing. As soon as details of the recovery schedule are available they will be reported here.




    02 December 2003: Planning December 2003 to February 2004

    The planning documents (OSDF, SIM_SDMOP, State_Summary and Geolocation) for the next planning cycle have been put onto the website. This time interval covers the orbits 9361-10247 (December 15th to February 15th). All scheduled measurements are nominal. Note that in January the lunar occultation season starts again since moonrise will occur on the nightside of Earth.

    Around X-mas/New Year the measurements will be interleaved with the planned non-nominal decontamination. Thus measurement data will be of degraded quality from about December 18th to January 3rd.




    28 November 2003: Next decontamination

    Yesterday it was decided to run the next non-nominal decontamination in the second half of December. The warm-up phase will start December 17th/18th and the cool-down will end the period with elevated temperatures January 2nd/3rd. The total warm-up phase will last 375 hr, i.e. it is identical to the non-nominal decontamination in August. Nominal thermal conditions are expected January 5th/6th.

    This decontamination planning is compliant with instrument calibration requirements (monthly calibration), the schedule of validation campaigns in January/February and operational constraints in the X-mas/New Year period. The exact decontamination date will be reported here once detailed special operations planning information is available.




    20 November 2003: New monitoring table

    Following the discussions at the SCIAMACHY IOP meeting we decided to generate a new monitoring table listing the time intervals when no measurement data do exist, although the original SCIAMACHY planning had foreseen routine or special operations at that time. This table is entitled "Data Unavailability History" and can be found under Data Unavailability History in the "Instrument Monitoring" section. The reason for data unavailability can either be expected operation interrupts, instrument/spacecraft malfunctions or ground segment problems.

    Note that all related entries in the table Data Quality History are therefore removed. This table is now again a clean record of phases when the data quality was not as specified.




    05 November 2003: Solar activity and light path monitoring

    The light path monitoring plots displayed for end of October 2003 a somewhat unusual behaviour such that the throughput as derived from Sun measurements increased after a significant drop. No obvious cause could be found on spacecraft or instrument level.

    The event, however, occurred in a period of strong solar activity. We browsed space weather information available, particularly sunspot data in order to look for a possible correleation with the observed SCIAMACHY throughput. Fig. 1 shows the effective solar disk area as derived from the corrected sunspot area which is given in the Solar Indicies provided by the Space Environment Center. It is obvious that end of October the solar disk was covered with large sunspots (fig. 2 - taken from Big Bear Solar Observatory). The sunspot area amounted to 5.7 x 10-3 of the solar hemisphere. A reduced flux due to sunspots is currently the best explanation for the observed throughput behaviour. Analysis is ongoing whether sunspots and throughput exhibits a correleation since the beginning of SCIAMACHY's monitoring activities in August 2002. Additionally, the spectral dependance between solar flux and observed decrease in throughput requires further investigations.

    Fig. 1: Effective solar disk area as a function of date (sunspot area taken from NOAA's Space Environment Center) Fig. 2: White-light image of solar disk on October 27, 2003 (Big Bear Solar Observatory)




    05 November 2003: Parameter table update

    A new support table, which lists the relation between state ID, measurement category and RTCS configuration (status of mechanisms and lamps), has been added to the list of measurement parameter tables. This table can be found under Measurement category / RTCS (Support) with a brief description given in Measurement Parameter Tables Description.




    24 October 2003: Measurement interrupt

    As previously announced by ENVISAT, an out-of-plane manoeuvre together with a flight software update is planned on October 28th. SCIAMACHY will be commanded into MEASUREMENT IDLE for the time period 02:55 UTC to 18:20 UTC of that day. Thus no temperature degradation will occur and measurement data will be of nominal quality right at the re-start of MPS driven operations.




    24 October 2003: November/December planning

    The planning documents for the period November 15th - December 15th (orbit 8932-9360) can be found on the SOST webpages (OSDF, SIM_SDMOP and Geolocation) Only nominal measurements are executed within that time interval.




    17 October 2003: Possible measurement interrupt

    ENVISAT announced an out-of-plane manoeuvre for October 28th. SCIAMACHY has to be commanded into MEASUREMENT IDLE for this time period of a few hours. It is also discussed whether the manouevre is combined with an ENVISAT onboard s/w update. If this would be the case SCIAMACHY would be switched off for a short period. A more detailed time schedule will be provided here once it is available.




    15 October 2003: Improved limb/nadir matching implemented

    In orbit 8489 the timeline and state modifications required for the improved limb/nadir matching as described in OCR 11 was successfully implemented onboard. This comprised the upload of 12 modified State Duration and 12 Scanner State tables for all wide and small swath limb states. The new timeline set 31 replaces now the previous timeline set 25 for routine measurements (wide swath).




    29 September 2003: Limb/nadir matching implementation

    In orbit 8489 the improved limb/nadir matching as described in OCR 11 and successfully tested early September will be implemented onboard. This comprises the upload of 12 modified State Duration and 12 Scanner State tables for all wide and small swath limb states. In addition, the complete timeline set 25 for routine operations has to be overwritten. From orbit 8489 onwards, routine measurements in wide swath mode will be executed with timelines of set 31. These timeline definitions have been added to the SOST webpage.

    Note that the currently defined timelines with the non-standard small swath width or limb only sequences also require new definitions. This will be done after October 15th.




    29 September 2003: October/November planning

    The planning documents for the period October 15th - November 15th (orbit 8488-8931) can be found on the SOST webpages (OSDF, SIM_SDMOP and Geolocation) This interval includes, in orbit 8489, the implementation of the improved limb/nadir matching.




    10 September 2003: October planning, part 1

    The planning documents for the period October 3rd - 15th (orbit 8316-8487) can be found on the SOST webpages (OSDF, SIM_SDMOP and Geolocation) This interval was kept short in order to allow for an on-board implementation of the modified limb states and timelines (improved limb/nadir matching, see OCR 11) mid of October, provided that the final OCR approval is obtained in time.




    08 September 2003: ENVISAT recovery/SCIAMACHY back to operations

    ESA's failure analysis of Thursday's ENVISAT PLSOL revealed rather quickly the cause of this event. Therefore ESOC successfully started a fast recovery over the weekend.

    For SCIAMACHY this resulted in a transition to HEATER on Saturday, September 6th at 15:41 UTC. HEATER mode was achieved on Sunday, September 7th at 08:50 UTC. The same day, in orbit 7954 (ANX at 17:49:25 UTC), SCIAMACHY began to execute the nominal MPS schedule again. Thus it is not required to modify the planning in order to save the September monthly calibration, as initially expected. Tuesday afternoon, when the monthly calibration orbits are due, the detectors will be thermally stable again.



    05 September 2003: ENVISAT payload switch-off

    In orbit 7914, 22:52:52 UTC (September 4th), an anomaly occurred onboard ENVISAT which triggered a switch-off of the complete payload. Failure analysis is ongoing. As soon as details of the recovery schedule are available they will be reported here.

    Most likely the September monthly calibration in orbits 7983-7986 will be affected. Therefore it is intended to provide a replanning with a monthly calibration sequence - without lunar measurements - shifted by about 1 week.




    03 September 2003: Limb/nadir matching test

    The test to improve the limb/nadir matching (see OCR 11), which had failed mid of August, was successfully repeated in orbits 7862-7889. Measurement data analysis is ongoing to ensure correct definition of states and timelines. Once this anlysis has confirmed the selected approach and project management and SSAG have accepted the modification, SOST will implement the associated states and timelines in one of the next planning cycles for early October. This implementation will require the definition of complete new timeline sets, i.e. the exchange of all onboard and onground timelines for nominal operations.




    01 September 2003: Decontamination status

    The long non-nominal decontamination ended last week on August 27th (orbit 7798) at 21:36 UT. Total planned warm-up time was 375 hr but due to the HTR/RF transition caused by an incorrect parameter setting for the limb/nadir matching test for about 28 hr the heating was slightly reduced since only the decontamination heaters were left on. After the instrument had been transferred back to HEATER mode (August 16th/17th), the non-nominal decontamination continued without problems.

    The figures below provide an overview of the detector and OBM temperature history during the decontamination (for detector temperatures only detectors 1&2 are displayed). The longer gap in the detector temperature is caused by the fact that temperature readings are only available when timelines are running while the OBM parameters are generated also when being in HEATER mode. The OBM temperature curve indicates that non-nominal decontamination heating was only disturbed for a short interval < 30 hrs.

    Fig.: Detector (1&2 - left) and OBM (right) temparture history for the decontamination with warm-up starting on
    August 12th and cool-down starting on August 27th.



    18 August 2003: Transfer to HTR/RF and recovery

    At the beginning of the test measurements on August 16th (orbit 7633) - scheduled to confirm the approach in limb/nadir matching improvement (OCR 11) - an OOL occurred which sent SCIAMACHY into HTR/RF. The reason for the OOL is understood. It was an incorrect parameter setting in the onboard parameter State Duration table causing a mismatch between measurement execution and actual state configuration. Recovery was initiated immediately. The transfer to HEATER mode was started in orbit 7640 (August 16th) and MPS driven operations in final flight configuration were achieved from orbit 7664, 12:57 UT (August 18th) onwards. The test measurements were lost and have to be repeated at a later date (proposed date is September 1st/2nd).

    The transfer to HTR/RF interrupted the running long decontamination. With the transfer to HEATER mode, the decontamination continued. An ARB had decided to leave the decontamination settings unmodified, i.e. start of cool-down and finally reaching stable nominal conditions will be as described in the previous news.




    12 August 2003: Decontamination started

    In Orbit 7574 (August 12th), the warm-up phase of a long non-nominal decontamination was started. The warm-up phase will last 375 hrs. On August 27th (orbit 7798) warm-up will be terminated and after approx. 48 hrs detectors 1-6 will have established nominal temperatures again (56 hrs for detectors 7/8). From orbit 7827 (detectors 1-6) and 7832 (detectors 7/8) onwards measurement data are expected to be of nominal quality. We hope that the throughput in channels 7 and 8 will show a significant improvement.




    29 July 2003: Next planning cycle

    The period between August 16th - October 2nd (orbit 7629 - 8315) has now been planned and the corresponding input is provided to ENVISAT. Associated documents (OSDF, SIM_SDMOP and Geolocation) can be found on the SOST webpages.

    This interval includes the test to improve the limb/nadir matching (OCR 11, orbit 7633-7660). Although specified as test measurements, no science data will be lost in that period. The test will run modified limb states with a maximum horizontal scan altitude of about 93 km, i.e. reduced duration. The resulting limb/nadir matching pattern is expected to improve as displayed in the sample figure below.

    Fig.: Current nominal limb/nadir matching (left) and improved limb/nadir matching (right) using shorter limb states

    Note that the long decontamination, starting around August 12th, will run as a 'background' task in the first 12 days of the new planning cycle. Measurement data from that interval will be of reduced quality.




    28 July 2003: SCIAMACHY back to operations

    The recent event, which had sent us to HTR/RF, was most probably caused by a Single Event Upset while passing the South Atlantic Anomaly. Recovery was completed successfully in orbit 7363 (July 28th) when SCIAMACHY picked up the MPS schedule at 12:15 UTC.




    25 July 2003: SCIAMACHY in HTR/RF

    In orbit 7309, (July 24th, 16:46 UTC), SCIAMACHY was commanded to HTR/RF after numerous SDPU anomalies. The cause of these anomalies is presently unknown and analysis is ongoing. We will provide more information here as soon as it is available, particularly when to resume the measurement plan.




    11 July 2003: Limb_mesosphere re-established

    The implementation of OCR 8 resulted in a limb_mesosphere start altitude of 250 km. Thus the associated measurement data were of no use. SOST has now modified parameter settings to re-establish the limb_mesosphere state. These parameters are due for upload July 21st (orbit 7265), i.e. from that time onwards the limb_mesosphere state will function again as specified.




    11 July 2003: Next decontamination

    Yesterday SCIAMACHY decided to execute the next decontamination in the 2nd half of August. Envisaged start of the warm-up phase will be around August 12th, shortly after the monthly calibration orbits. The duration of the warm-up phase will be extended to about 375 hrs, i.e 15 days. This is equivalent to the very long decontamination December 2002/January 2003 which yielded sofar the most significant improvement in channels 7 & 8 performance. Decontaminations with only 30 hr and 60 hr warm-up time, as done in April and May, turned out to be far less efficient in removing the ice. We hope that after the very long decontamination in August we'll see channels 7 & 8 to reach a higher stable throughput than presently observed.

    Planning the decontamination end of July in order to have the instrument well set for the onset of the Ozone hole in August was also considered. However it was impossible to implement this option since the UTOPIHAN and CONTRACE campaigns will last until July 25th and they provide good opportunities for comparisons with SCIAMACHY data.

    Note that the data will be of reduced quality for the complete decontamination (warm-up and clean-up phase).




    09 July 2003: Timelines for all mission scenarios

    SOST has now implemented in the ENVISAT ground segment all timelines required for the execution of the following mission scenarios:

  • alternating limb/nadir with small swath (timeline_set 26)
  • nadir only with wide swath (timeline_set 27)
  • nadir only with small swath (timeline_set 28)
  • limb only with wide swath (timeline_set 29)
  • limb only with small swath (timeline_set 30)

  • The timelines cover the illuminated part of the orbit. Some do include a sub-solar state such that they support daily and weekly calibration orbits. All timelines are used by the ENVISAT MPS in the same way as the timelines for the standard alternating limb/nadir measurements with wide swath (timeline_set 25). For detailed information concerning the state sequences please check the timelines on the SOST webpage.

    Note that there exists the limitation to execute the above mentioned mission scenarios only when the moon is not observed. Including the monthly moon visibility period would have required the definition of more than 80 additional timelines - a number which is in conflict with operational requirements.

    The new mission scenarios are presently not part of routine operations. Including them in nominal planning requires the issue and approval of an OCR.




    01 July 2003: Next planning cycle

    The period between July 16th - August 15th (orbit 7185 - 7628) has now been planned and the corresponding input is provided to ENVISAT. Associated documents (OSDF, SIM_SDMOP and Geolocation) can be found on the SOST webpages. This interval includes the repetition of the memory effect measurements (OCR 9, orbit 7193/7194). All other orbits are filled with nominal measurements.




    17 June 2003: OCR 9 to be repeated

    The measurements to characterize the memory effect in detail (OCR 9) have to be repeated. Originally scheduled in orbit 6778/6779 (June 17th), the actual state execution yielded no data in channels 1-5 and partially saturated values in channels 6-8. The reason was a combination of PET and co-adding settings which resulted in a data rate overflow.

    Note that it has been decided to repeat the memory effect measurements with modified PETs and co-adding factors in orbit 7193/7194 (July 16th).




    22 May 2003: OCR 8 / limb_mesosphere

    OCR 8, which requests a change in the altitude for dark current measurements from 150 km to 250 km, will be implemented in orbit 6456 (May 26th). Implementation is accomplished by modifying basic profile no. 9. Since this profile is also used by the limb_mesosphere state, this state will start the scans at an altitude of 250 km as well. Thus the limb_mesosphere vertical scan range will no longer be 80-150 km but 180-250 km, i.e. the associated measurement data will be obsolete until further notice.

    Investigations are ongoing to modify the limb_mesosphere state such that the original measurement goals can be achieved again.




    22 May 2003: June, part 2 / July planning

    The planning documents for the period June 17th - July 16th (orbit 6770-7184) can be found on the SOST webpages (OSDF, SIM_SDMOP, Geolocation). In this period nominal measurements will be executed, except for orbits 6778 and 6779, where special measurements in support of OCR 9 are planned.




    21 May 2003: Decontamination started

    Shortly after resuming MPS driven operations, SCIAMACHY started the 60 hr warm-up phase of a long non-nominal decontamination in orbit 6384 (May 21st, 02:46:18 UTC). In orbit 6420 (May 23rd, 15:07:41 UTC), the warm-up will end and cool-down starts. We will reach stable thermal behaviour in detectors 1-6 at about 15:00 UTC, May 25th.




    20 May 2003: June planning, part 1:

    The planning documents for the period June 9th - June 16th (orbit 6656-6769) can be found on the SOST webpages (OSDF, SIM_SDMOP, Geolocation). Note that this is the period where the last moon occultations for 2003 can be planned. With the start of the July lunar visbility window, moonrise will occur on the dayside, i.e. no moon measurements will be possible starting at an altitude of 17.2 km.




    19 May 2003: May reduced operations:

    As announced in the previous news, ENVISAT recently entered a period with reduced operations. In orbit 6344 (May 18th, ANX 06:53:10 UTC), SCIAMACHY's MPS schedule had been interrupted in preparation of the PMC patch/manoeuvre activities. The MPS schedule will be resumed in orbit 6383 (May 21th, ANX 01:08:02 UTC) and the window for the long non-nominal decontamination will start.




    08 May 2003: May operations:

    In the last week, SCIAMACHY executed successfully the specific non-linearity measurements for channel 8 (orbit 6090-6109) and 3 days with nadir_pointing (orbit 6130-6174). Currently the instrument performs nominal measurements.

    As announced by ESA, ENVISAT operations will be reduced between May 18th and 25th. An out-of-plane manoeuvre and an onboard s/w upgrade will cause the payload to be switched off, starting May 18th. After resuming instrument operations May 20th/21st, the usage of the Artemis relay could lead to a limited availability of low rate data until May 25th.

    Therefore SCIAMACHY decided to execute a long non-nominal decontamination in that time period. It is expected that detectors will achieve thermal stabilitiy again around May 26th/27th and routine operations continue thereafter. Details of the period with reduced ENVISAT operations and the SCIAMACHY decontamination will be provided here as soon as they are available.




    24 April 2003: Completion of delta SODAP measurements:

    By 7:09 UTC this morning (orbit 6000), SCIAMACHY finished the measurement window dedicated to the repetition of the configuration_13 delta SODAP measurements (S_DIFF_VAR and Dark_1-20), which were lost beginning of December 2002 due to an instrument anomaly. The successful conduct of these measurements completes now the execution of SODAP activities.




    10 April 2003: Next planning cycle:

    The period between April 30th - June 8th (orbit 6090 - 6655) has now been planned and the corresponding input is provided to ENVISAT. Associated documents (OSDF, SIM_SDMOP and Geolocation) can be found on the SOST webpages. This interval includes the implementation of the non-linearity measurements for channel 8 (OCR 3, orbit 6090-6109) and the execution of 3 days with nadir_pointing states (validation requirement, orbit 6130-6174). All the remaining orbits are filled with nominal measurements.

    Note that the timelines for the non-linearity measurements are listed under Timelines/Special/Set_09 while those for nadir_pointing can be found under Timelins/Validation/Set_08.




    04 April 2003: Non-nominal decontamination

    In orbit 5718 (14:12:14 UTC, April 4th) a non-nominal decontamination starts with a short warm-up phase of 30 hrs. Cool-down will end about 78 hrs later, i.e. thermal stability in channels 1-6 is expected at about 20:15 UTC, April 7th (channels 7 & 8: 04:15 UTC, April 8th). The measurement data in the decontamination period have degraded quality.




    03 April 2003: More OCR information:

    Under 'Operations Modification' a bullet 'OCR implementation' has been added which provides more details about the implementation of approved OCRs. The complete OCR can be accessed as well as information on modified mission scenarios, states and timelines. This page should help to identify changes in the on-board instrument configuration due to implemented OCRs.




    03 April 2003: April planning, part 2:

    The planning documents for the period April 23rd - April 30th (orbit 5983-6089) can be found on the SOST webpages (OSDF, SIM_SDMOP, Geolocation). This period includes, between orbits 5983-6000, the repetition of the configuration_13 delta SODAP measurements (S_DIFF_VAR and Dark_1-20), which were lost last December due to an instrument anomaly. The remaining part of the planning interval consists of nominal limb/nadir observations.




    31 March 2003: Nadir swath modification:

    In order to correct for the vignetting of the readouts on the extreme right position in nadir observations, OCR no. 2 has been implemented. From orbit 5656 (March 31st) onwards the nadir scans are shifted by 2° LOS to the left, i.e. they are asymmetric w.r.t. the ENVISAT ground track. No obscured ground pixels should occur on the right side of the swath. The test phase will last 8 days. If no vignetting can also be detected on the left side, this nadir setting could become the default final flight configuration.

    Meanwhile, in orbit 5771 (April 8th), only the right side of the nadir swath will be shifted by 1° to the left - compared to the original nadir settings - to ensure obscuration free nadir measurements until it is decided whether to implement the swath from the test phase. The resulting nadir across track swath width will be 63° (LOS) with a slightly reduced asymmetric location around the ENVISAT groundtrack.




    21 March 2003: Planning modification:

    Next Wednesday (March 26nd), a monthly calibration (without moon) has been inserted into the measurement plan to compensate for the regular monthly calibration which was lost due to the March 15th switch-off. This calibration replaces 5 orbits with nominal measurements (orbit 5592-5596).




    21 March 2003: SCIAMACHY off ..... and on:

    Yesterday (orbit 5502, March 20th, 10:57 UTC), SCIAMACHY's ICU was suspended caused by the 'well known' MCMD CCA check error. The reason for this error to occur again is well understood (missing corrective s/w patch during recent switch-on) and recovery had started immediately. The transition to HEATER was initiated in orbit 5506 (17:41 UTC), i.e. thermal stability in detectors 1-6 can be expected around March 22nd, 13:00 UTC.




    19 March 2003: April planning, part 1:

    The planning documents for the period April 4th - April 22nd (orbit 5711-5982) can be found on the SOST webpages (OSDF, SIM_SDMOP, Geolocation). Note that this period includes the time interval where a non-nominal decontamination is planned, i.e. the data obtained during the decontamination will be of degraded quality.




    19 March 2003: SCIAMACHY back to operations:

    Successful recovery of ENVISAT operations occured in the past few days. SCIAMACHY resumed MPS driven operations in orbit 5481 (March 18th, ANX 23:28 UTC). For detectors 1-6, thermal stability was reached around noon/March 19th while detectors 7 & 8 took a bit longer.




    17 March 2003: Next decontamination:

    As agreed with calibration experts, SOST submitted the first SCIAMACHY Operation Request (SOR) to ESOC to initaite a short non-nominal decontamination. The 30 hr warmup phase of the decontamination will start April 4th and end about 78 hr later (channels 1-5). The exact decontamination times will be reported here once the SOR has been transferred at ESOC into a Special Operation Request for implementation. Note that measurements continue throughout the decontamination period. Data analysis has to take into account that the data will be of degraded quality for a period which will be listed in the Data_Quality_History page.




    15 March 2003: ENVISAT payload switch-off:

    In orbit 5426 (March 15th), an anomaly occurred onboard ENVISAT which triggered a switch-off of the complete payload. It seems that the anomaly was related to an Artemis test. No further details are currently available. Recovery has started and it is expected that SCIAMACHY is back to the MPS schedule in stable conditions around late Wednesday (March 19).




    14 March 2003: Final Flight state description:

    The description of the Final Flight states as uploaded December 2002 is now completed and put on back on the SOST website (State Description). It provides for each state detailed information w.r.t.

  • line of sight
  • scan strategy
  • swath control
  • measurement duration
  • integration time
  • ground pixel size

  • The state description and the RAM measurement parameter tables are compliant and will be updated whenever an OCR requires to implement stable modifications on state level.




    14 March 2003: Monitoring information:

    We have included now monitoring information on the SOST webpage. This information covers various aspects of

  • anomalies
  • thermal configuration
  • operational detector temperature, OBM and PMD control
  • data quality

  • In addition, the status of LLIs is maintained and a link to a SOST-IFE monitoring page presenting light path results is provided. The operational detector temperature, OBM and PMD control fulfilles the requirements of the associated procedures PIN 401, 402 and 404 as described in the IOM. Each monitoring item contains a brief conceptual description plus dynamic information which is dervied by SOST on regular timescales, when applicable.





    26 February 2003: OCR description:

    We have added a brief description of the Operations Change Request (OCR) concept to the SOST web pages (see Operations Modification). This concept is the baseline to modify final flight operations The page also includes access to the OCR template file. In addition, the current status of submitted OCRs is presented.




    24 February 2003: Modified planning:

    Caused by the SCIAMACHY anomaly in orbit 5034 and a series of warnings related to the execution of the moon_troposphere state in the February lunar visibility window, it was required to modify slightly the mission planning for February and March. In February a 'quasi' monthly calibration will now be executed on February 27th (orbits 5206-5210) to compensate for the lost monthly calibration in orbits 5048-5052. In March all moon_troposphere timelines have been removed and regular moon measurements starting at 17.2 km have been inserted instead. The associated planning files have been updated and put on the SOST webpages.




    24 February 2003: SCIAMACHY back to operations:

    The recovery of ENVISAT operations succeeded over the past weekend. SCIAMACHY resumed MPS driven operations in orbit 5136 (February 22nd, ANX 21:02 UTC). For detectors 1-6, thermal stability was reached around early February 23rd while detectors 7&8 took a bit longer.




    20 February 2003: SCIAMACHY recovery and ENVISAT payload switch-off:

    The recovery of SCIAMACHY operations after the anomaly in orbit 5034 was successfully accomplished in orbit 5073 (February 18th) when MPS driven operations were resumed. The thermal stability of detectors 1-6 was then reached February 19th around 13:00 UTC while detectors 7 & 8 took a bit longer (February 20th, around 05:00 UTC).

    Unfortunately, the ENVISAT Payload Management Computer (PMC) experienced a problem in the morning of February 20th requiring the complete payload to be switched off in orbit 5099 (07:27 UTC). Currently nominal operations are suspended. Details about the planned recovery will be reported here once they are available.




    17 February 2003: Transfer to R/W WAIT mode:

    SCIAMACHY was transferred to R/W WAIT in orbit 5034 (February 15th, UTC 19:15:23). Detailed analysis indicates that the MCMD CCA check error, which interrupted SODAP measurements frequently last year between May-July, is the cause of the current anomaly. In the course to correct this error several operational counter-measures had been implemented and a s/w patch was loaded in October. This patch strongly reduced the probability for this error to occur. It took now about 7 months until SCIAMACHY was struck again by this type of anomaly.

    Recovery has been started and it is expected that detectors 1-6 will become thermally stable Wednesday afternoon, detectors 7 & 8 require an additional 16 hours.

    Due to the anomaly we lost the monthly calibration orbits for February. Since the lunar visbility window closes February 17th, it is impossible to fully repeat the monthly calibration. However, replanning has started to execute all 5 calibration orbits without the associated moon measurements as quick as possible. Earliest possible date is February 27th. The modified OSDF and SIM_SDMOP can be found on the SOST webpages in the near future.




    12 February 2003: New planning files:

    The new planning files (OSDF, SIM_SDMOP, Geolocation) for SCIAMACHY's routine operations between March 4th (orbit 5267) and April 3rd (orbit 5710) is now available on the SOST webpages. The geolocation files for the time interval March 6th (orbit 5296) - March 12th (orbit 5395) display the flight route of the Falcon aircraft for the March northern validation campaign as currently defined. Since this campaign covers an area where Sun occultations occur, the limb maps show in addition the geolocation of the tangent point for a LOS to the solar center at an altitude of 20 km.

    Details of the Falcon northern campaign can be found below. For completeness we also list the current schedule of the southern campaign which will start February 19th.

    North  
    Thursday, 06 March Oberpfaffenhofen - Kiruna/Sweden
    Friday, 07 March Kiruna - Kiruna via Ny Alesund
    Saturday, 08 March Day off (Kiruna)
    Sunday, 09 March Kiruna - Keflavik/Iceland
    Monday, 10 March Keflavik - Sondre Stromfjord/Greenland with turn at 060 West
    Tuesday, 11 March Sondre Stromfjord - Keflavik
    Wednesday, 12 March Keflavik - Oberpfaffenhofen
    South  
    Wednesday, 19 February Oberpfaffenhofen - Tozeur/Tunisia
    Thursday, 20 February Tozeur - Niamey/Niger - Yaounde/Cameroon
    Friday, 21 February Day off (Yaounde)
    Saturday, 22 February Yaounde - Nairobi/Kenia
    Sunday, 23 February Day off (Nairobi) - press conference
    Monday, 24 February Nairobi - Mahe/Seychelles
    Tuesday, 25 February Day off (Seychelles)
    Wednesday, 26 February Mahe - Nairobi
    Thursday, 27 February Day off (Nairobi)
    Friday, 28 February Nairobi - Yaounde
    Saturday, 01 March Yaounde - Tozeur
    Sunday, 02 March Day off (Tozeur)
    Monday, 03 March Tozeur - Oberpfaffenhofen



    04 February 2003: Time reference information added:

    We have added to the SOST webpage information concerning the difference between actual and planned times (Time Reference). As all planning files rely on the reference orbit and the actual orbit might slightly change within specified limits, the absolute times along the actual orbit can differ from the times derived from the reference orbit by up to ±10 sec. The actual time is taken from a prediction of the actual orbit provided by FOCC, the reference time is taken from the Reference Orbit Event file. Time difference information is displayed as time difference (in sec) versus orbit number. For each year a separate plot is generated.




    16 January 2003: Final flight state tables available:

    The measurement parameter tables of the final flight state configuration FFS_021215, which was loaded onboard December 15th and which is running since then, are now available on the SOST webpage under RAM - Parameters. Note that we have added the integration_time_support table which informs about the integration times as a function of cluster index.

    The descriptions of the final flight states will follow soon. The associated page State Descriptions is currently being updated.




    09 January 2003: New planning files:

    The new planning files (OSDF, SIM_SDMOP, Geolocation) for SCIAMACHY's routine operations between January 15th (orbit 4580) and March 3rd (orbit 5266) is now available on the SOST webpages. The geolocation files for the time interval February 19th (orbit 5081) - March 3rd (orbit 5266) displays the flight route of the Falcon aircraft for the February southern validation campaign as currently defined.




    07 January 2003: HEATER/REFUSE and recovery

    SCIAMACHY operations over X-mas and New Year were rather smooth until January 4th, when a transfer to HEATER/REFUSE occurred in orbit 4428. This event was very close - but unrelated - to terminating the extended non-nominal decontamination warm-up phase. Details of the anomaly can be found in the text below which was copied from a mail message from Astrium.

    On January 4, 2003, at 11:25:42 UTC SCIA has been safed to Heater/Refuse mode. The reason for this safing event is probably an SET (Single Event Transient) in the PMTC / ASM control electronics.

    The safing occurred about 4 minutes before the planned termination of the Non-Nominal Decontamination warmup. However there are no indications that the safing is related to this event.

    The corresponding commands for the termination of the Non-Nominal Decontamination warmup were executed as scheduled with SCIA in Heater/Refuse mode. The Decontamination heaters have been switched off and the thermal parameters of the ATC and TC were set back to the nominal value, in preparation for the recovery to Heater mode.

    Finally SCIA has been recovered to Heater mode January 6, 2003, around 09:21 UTC, being followed by the execution of timeline TL_63. The original MPS schedule has been picked up at 12:08:59 UTC on the same day.

    Thermal stability should be reached as follows:
    Channel 1 ...6 : January 8, 2003, at 09:30 UTC
    Channel 7 & 8: January 8, 2003, at 21:30 UTC


    Thus the dark current test on Januray 9th can be executed as planned.




    20 December 2002: Operations support over X-mas/New Year

    SCIAMACHY operations over the X-mas/New Year period will consist of the extended non-nominal decontamination (end of cooldown occurs in orbit 4464, January 6th) and the execution of nominal measurements from orbit 4204 (December 20th) onwards. The SOST webpages provide currently access to the planning files up to January 15th. Operations support over the holiday period will be limited to urgent requests in case of anomalies. From January 6th (IFE) and 7th (DLR) on, SOST will be fully operational again.

    The planning for the time period January 15th- March 3rd has been submitted to ENVISAT. The associated planning files will be put onto the webpages early January. They will cover phases with dedicated validation campaigns (e.g. Falcon in second half of February).

    The SCIAMACHY Operations Support Team wishes everyone involved in the SCIAMACHY mission Merry Christmas, a happy New Year and all the best for 2003. Let's hope that 2003 will add another successful year to our mission.




    17 December 2002: December planning - part 3:

    The SCIAMACHY measurements for the 2nd half of December (starting with orbit 4182) have been planned and submitted to ENVISAT. The associated plans (OSDF, SIM_SDMOP, Geolocation) can be found on the SOST web pages.

    With the implementation of the final flight settings the plan does mainly list routine measurements. These start in orbit 4204 and continue throughout the extended period with non-nominal decontamination. Early next year (January 9th) a one day period with the already tested nadir states including a dark current phase is planned. This should help to find the best dark current correction approach.




    17 December 2002: SOST website inaccessible tomorrow:

    Due to refurbishment of DFD/IMF's network facilities, the SOST website cannot be accessed on December 18th. On Thursday morning the network services shall be available again. Please note that the refurbishment will last until early 2003. At the end of this period the SOST website will be inaccessible again for a few days. This is presently scheduled for January 4th - January 6th.




    16 December 2002: ASM diffuser state modified:

    While implementing the final flight states it was realized that the basic profile settings for the azimuth scanner contained incorrect parameters. These caused all previous ASM diffuser measurements to be taken with an incorrect observation geometry (diffuser normal was phase shifted by 180º). The basic profiles settings have been corrected and a first ASM diffuser measurement was scheduled in orbit 4163 (December 16th).




    12 December 2002: Another HEATER/REFUSE and recovery:

    In orbit 4093 (December 12th) there was another transfer to HEATER/REFUSE, triggered by an incorrect parameter setting of a state in one of the last delta SODAP configurations (configuration 13). The problem is understood and MPS driven operations resumed in orbit 4110. The current measurement plan is maintained. It still has to be decided how to proceed with the not executed delta SODAP measurements between orbits 4093 - 4109.




    06 December 2002: December planning - part 2:

    The results of the planning period December 11th - 17th (orbit 4084 - 4166) are now available on the SOST webpage OSDF, DMOP, Geolocation - the currently missing State_Summary files will be added next week). Most important event in that phase is the upload of the final flight state and timeline configuration. In orbit 4151 SCIAMACHY will be operated for the first time in that configuration to execute nominal measurements. The table below summarizes the planned activities.

    Date Orbit Activity
    11/12/02 - 13/12/02 4084 - 4116 configuration 13 - repeat (obj. TPD, DLR-DP)
    13/12/02 - 14/12/02 4117 - 4127 configuration 14, incl. moon (obj. DLR-SOST, TPD)
    14/12/02 - 15/12/02 4128 - 4142 nadir_only, small swath
    15/12/02 4143 - 4149 final flight configuration, states unused in routine
    operations
    15/12/02 - 17/12/02 4150 - 4166 final flight configuration, nominal measurements incl.
    monthly calibration

    From orbit 4167 onwards re-initialization of the instrument and a subsequent long non-nominal decontamination are planned. MPS driven routine operations using the final flight states and timelines will start during the decontamination phase. Note that early January a specific test to compare the dark current correction using the 5 dark current states and modified nadir states (from delta SODAP, incl. a dark current phase at the end of the state) will be executed for a total of 14 orbits.




    06 December 2002: Final flight configuration achieved:

    With the definition of the current final flight states (FFS_021215) and timelines (FFT_021215) last week, SCIAMACHY will soon be operated in that configuration. The final flight states and timelines do not deviate much from the consolidated beta configuration which was executed during nominal operations since mid July. On state level the most significant modification is the addition of two more dark current states (ID 8 and 26) to improve the dark current correction and the addition of two limb states (ID 34 and 41) for specific orbital phases.

    Final flight states and timelines will be described on the SOST webpage as soon as the delta SODAP activities in December have ended and more time can be spent on website updates.




    04 December 2002: Another HEATER/REFUSE and recovery:

    In orbit 3981 (December 4th) there was another transfer to HEATER/REFUSE, triggered by an incorrect parameter setting of a state in the consolidated beta state configuration. The problem is understood and corrective actions have started. Impact on the current schedule is negligible.




    02 December 2002: ..... and back to MEASUREMENT:

    Due to a very fast recovery done by ESOC, SCIAMACHY reached MPS driven operations again in orbit 3958. The measurement plans from that orbit onwards remain valid. The lost 2 days of delta SODAP activities will now be scheduled between orbits 4084-4116. Once the associated plans are available they will be provided via the SOST webpages.




    02 December 2002: SCIAMACHY in HEATER/REFUSE:

    In orbit 3925 (November 30th) SCIAMACHY was sent to HEATER/REFUSE. The cause was the setting of onboard parameter tables which was incompliant with the executed states. Affected were delta SODAP measurements. It is planned to reconfigure the instrument in orbit 3958 and resume MPS driven operations afterwards.

    When and how to repeat the lost 2 days of delta SODAP activities will be decided today.




    27 November 2002: December planning:

    In December SCIAMACHY will execute the remaining SODAP/commissioning tasks. These include MPS driven measurements and thermal tests. The MPS driven schedules can be found on the SOST webpages as usual. However the planning cycle of the delta SODAP operations is much shorter than for nominal operations and modifications based on the actual progress have to be implemented. Thus only the plans for the forthcoming week is always presented. Currently this includes the time period up to December 11th. The table below lists the presently planned delta SODAP activities.

    Date Orbit Activity
    26/11/02 - 27/11/02 3866 - 3879 nadir pointing left_16 (obj. SRON)
    27/11/02 - 28/11/02 3880 - 3893 nadir pointing rigth_16 (obj. SRON)
    28/11/02 - 29/11/02 3894 - 3921 dark current (obj. SRON)
    29/11/02 - 02/12/02 3922 - 3962 configuration 13 (obj. TPD, DLR-DP)
    02/12/02 - 03/12/02 3963 - 3978 configuration 14 (obj. DLR-SOST, TPD)
    04/12/02 - 09/12/02 3983 - 4054 engineering
    09/12/02 - 11/12/02 4055 - 4083 nadir_only wide swath, limb_only small swath

    As many orbits execute specific states there will be only a few nadir/limb geolocation files. The sequence of scheduled states (incl. specific states) per orbit can be found in the State_Summary files.




    21 November 2002: SCIAMACHY Realtime Orbit Display:

    The SOST webpage provides now a link to our SCIAMACHY Realtime Orbit Display (SROD) - see icon What is SCIAMACHY doing? in top-right corner of the webpage. The SROD is intended to provide the actual state/timeline related measurement status as derived from mission planning. As long as instrument operations do exactly follow these plans, the SROD can be considered as a representation of what is going on on-board. Only the difference between reference time and actual execution time (max. 5-10 sec) is still applicable. However note that unexpected deviations from the plans cannot be compensated. In such cases we try to adjust the SROD as quick as possible.

    The SROD is calculated every 5-10 sec by using several outputs from the SOST mission planning tools. It displays ENVISAT orbit track and limb/nadir ground pixels similarly to the SOST limb/nadir geolocation maps. Additionally, ENVISAT's current position is indicated. The display description lists absolute orbit number, date, actual time in UTC and geolocation (longitude/latitude) as well as the instrument status (Measurement, Measurement Idle or Below Measurement), current timeline (ID, Set-ID, Sub-ID) and current state (ID, description and index in case of nadir/limb states).

    In the coming weeks we will test how robust the SROD environment behaves under operational planning conditions. If you have comments or suggestions, please contact us.




    21 November 2002: Full nadir/limb matching achieved:

    Yesterday's (November 20th) PMTC patch in orbit 3784 corrected a sign error in the scanner control software for limb states. This error caused an across-track shift of the limb ground pixels. Analysis of level 0 data received after the patch at SOST-DLR (fig. 1) and SOST-IFE (fig. 2) does no longer show this feature. The azimuth scan angles are found to be as expected, i.e. geolocation of nadir and limb pixel now display the desired along- and across-track matching matching.

    Fig. 1: Azimuth scan angles in limb states of orbit 3789.
    The measured angles coincide exactly with the expected
    ones.

    Fig. 2: Nadir/Limb matching of orbit 3790.
    The matching is now as expected and the across-track shift
    in limb pixels has disappeared.



    20 November 2002: Recovery after Leonids:

    The Leonid meteor shower occurred yesterday leaving ENVISAT untouched. SCIAMACHY's recovery back to the scheduled measurement plan is well underway. HEATER mode had been reached in orbit 3772 (November 19th, 14:35 UTC). Today (November 20th) a PMTC patch to correct a sign error in an on-board s/w module is planned (orbit 3784) and we will resume MPS driven measurements this evening in orbit 3789.




    18 November 2002: Test of Nadir states with dark current:

    As requested at the last SSAG meeting we implemented modified nadir states to test a new approach for getting dedicated dark current readings. The modified nadir states include a dark current phase at the end of each state. Thus dark current is obtained with the same settings as the associated nadir measurements. Since the total duration of the nadir states must remain unchanged, the time available for scientific measurements is reduced by either 10 sec or 20 sec (dependent on integration time).

    The test is scheduled to start in orbit 3836 and ends in orbit 3849 (November 24th). From orbit 3850 onwards we operate the nadir states as specified in the Consolidated Beta states. Once the data of the modified nadir states have been analysed, a decision has to be made whether the modified nadir states will define the baseline for the nadir measurement approach.




    14 November 2002: SCIAMACHY data interrupt and recovery:

    From orbit 3643 (November 10th) onwards, the ground segment in Kiruna was unable to generate level 0 data. However all available telemetry of SCIAMACHY showed nominal behaviour with no indication of an instrument anomaly. Analysis finally tracked the source of the anomaly to be most likely a spurious event in the link between SCIAMACHY and the High Speed Multiplexer (HSM) of ENVISAT which caused the data stream to be out of sync. Thus all measurement data were corrupted. In orbit 3697 (November 14th), the HSM was partially reset to establish synchronization again. This operation was successful and correct level 0 products are being generated from November 14th, 09:51:53 UT onwards.




    12 November 2002: New feature on web-page:

    The bullet 'Detailed Operations Plans' has been expanded to include now the planned SCIAMACHY state summary per orbit. This list shall replace the State History List, which was a SODAP specific effort by Astrium and which will not be maintained during routine operations. As long as the executed measurements are as planned, this list can be used to search for specific states in an orbit. Only the difference between reference time and actual state execution time has to be considered. The state summary files are ASCII files indicating associated timeline IDs, state IDs and state start/stop times (both UTC and elapsed time). More details can be found on the Detailed Operations Plan page.




    12 November 2002: Leonid meteor shower:

    According to current plans, ENVISAT and the instruments will be switched off for the expected strong Leonid meteor shower in orbit 3752 (November 18th, 04:30 UT) and will resume MPS driven measurements in orbit 3789 (November 20th, 19:00 UT). SCIAMACHY's transition from STANDBY to HEATER will start after orbit 3771 (November 19th, 13:00 UT) such that stable thermal conditions are expected around orbit 3806 (November 22nd, 00:00 UT).




    28 October 2002: ICU patch executed:

    In orbit 3399 (24th October, 13:11:28 UTC) TL 47 was not executed to perform an ICU patch (one word) to repair the MCMD Transfer CCA Check Error which several times in the past suspended SCIAMACHY operations.
    The execution of the patch was successful. Nominal operation has been resumed for TL 63 at 14:11:17 UTC.

    Note: October 30th the rate of the Auxillary Data MCMDs was set back from 1 MCMD/4sec to 1 MCMD/sec.




    28 October 2002: November measurement plans available:

    The SCIAMACHY measurements for November (orbits 3506-3921) have been planned and submitted to ENVISAT. The associated plans (OSDF, SIM_SDMOP) and geolocation files (Nadir, Limb) can be accessed on the SOST web pages.

    In November scientific measurements in support of validation campaigns until November 22nd are planned. They are identical to those executed in October. However, starting on November 18th, ENVISAT and the instruments will be prepared for the Leonid meteorite shower and likely PMC upgrade activities. Details are still tbd ESOC and will be provided here once they are available. For the PMC upgrade, SCIAMACHY will be switched off. Therefore, it can be expected that scientific measurements can only be obtained until midnight November 17th at the latest. The planned measurements from November 18th onwards will be overwritten by engineering activities as required.

    From November 26th on 4 consecutive days of delta SODAP are planned. They include remaining nadir_pointing_left/right and dark current measurements.




    24 October 2002: Bug in co-adding table corrected:

    A bug in the co-adding table 25 for clusters 15 & 16 has been discovered and will be corrected via CTI upload. The correct co-adding parameters are 8 and 1 (instead (1 and 8). The change will become effective from orbit 3478 (October 30th) onwards.




    11 October 2002: Geolocation in orbits 3324-3329 updated:

    The geolocation files for orbits 3324-3329 (October 19th) have been updated. Due to a mismatch in a configuration file not all nadir and limb states had been processed previously within these 6 orbits. The files on the geolocation website are corrected now and show all planned nadir and limb states.




    24 September 2002: October measurement plans available:

    The SCIAMACHY measurements for October (orbits 3063-3505) have been planned and submitted to ENVISAT. The associated plans (OSDF, SIM_SDMOP) and geolocation files (Nadir, Limb) can be accessed on the SOST web pages.

    In October only scientific measurements in support of validation campaigns will be executed. As lessons learned from the previous months are already available, some changes have been implemented in the quasi-nominal operations. They comprise

    All modified timelines can be accessed via the SOST website (timeline set 20).




    16 September 2002: Modified geolocation maps for Falcon campaign:

    As the Falcon Southern campaign has been shifted by 3 days, the nadir and limb geolocation maps have been updated accordingly. The flight route is now displayed in the maps of orbits 2834-3004. In addition, the route includes optional tracks between Palma de Mallorca and Yaounde and Nairobi and Mahe in order to optimize Falcon underpasses.

    The table below lists the modified Falcon southern flight.

    South  
    Sunday, 15 September Oberpfaffenhofen - Palma de Mallorca/Spain
    Monday, 16 September Palma de Mallorca - Ghardaia/Algeria - Niamey/Niger -
    Yaounde/Cameroon
    Tuesday, 17 September Day off (Yaounde)
    Wednesday, 18 September Yaounde - Nairobi/Kenia
    Thursday, 19 September Nairobi - Mahe/Seychelles
    Friday, 20 September Day off (Mahe)
    Saturday, 21 September Spare Day
    Sunday, 22 September Mahe - Nairobi
    Monday, 23 September Nairobi - Yaounde
    Tuesday, 24 September Day off (Yaounde)
    Wednesday, 25 September Yaounde - Niamey - Ghardaia - Palma de Mallorca
    Thursday, 26 September Palma de Mallorca - Oberpfaffenhofen (via Italy)



    08/11 September 2002: SCIAMACHY OCM/PMC upgrade interrupt:

    SCIAMACHY was switched off on Sunday, September 08th at 07:10:00 UTC in orbit 2737 for the preplanned ENVISAT activities OCM and PMC-S/W-update.
    On Tuesday, September 10th at 11:27:53 UTC in orbit 2768 SCIAMACHY was up in HEATER mode again. The MPS schedule was picked up after reconfiguration in orbit 2781. First Timeline executed same orbit at 09:56 UTC.

    It is expected that the detectors become thermally stable again on Thursday, September 12th at 07:30 UTC (channels 1 - 6) and on Friday, September 13th at 00:30 UTC (channels 7 & 8).




    28/29 August 2002: SCIAMACHY off.... and on again:

    SCIAMACHY went into ‘HEATER REFUSE mode’ on Wednesday, August 28th in orbit 2586. Details of the anomaly event and the recovery activities can be found in the summary below, taken from an e-mail message from Astrium:

    On Wednesday 28. August at 18:46 UTC SCIA was safed to Heater/Refuse mode. The safing has been triggered by an out-of-limit (OOL) of parameter I0270 Mechanisms Status OB. Monitor. The first OOL reading of I0270 was 71 decimal, which is the same value which triggered the safing of SCIA to Heater/Refuse mode on 12-June-2002 at 17:32 UTC. The safing on 12-June-2002 was explained by a Single Event Upset (SEU). We are working on the recovery scenario.

    On August 29th in orbit 2596, SCIAMACHY has been recovered to HEATER mode. The original MPS schedule was then picked up at 11:43 UTC the same orbit. It is expected that the detectors become thermally stable again on Saturday, August 31st at 03:45 UTC (channels 1 - 6) and 19:45 UTC (channels 7 & 8).




    14 August 2002: September measurement plan available:

    The SCIAMACHY measurements for September (orbits 2633-3062) have been planned and submitted to ENVISAT. The associated plans (OSDF, SIM_SDMOP) and geolocation files (Nadir, Limb) can be accessed on the SOST web pages.

    September is a period where validation measurements are mixed with a few SODAP measurements which have been left over from the previous months. The SODAP measurements are planned at September 1st, 2nd and 14th (full days), in orbits 3033/3034 and in orbits 3048/3049. No conflicts with validation campaigns are expected. The 2 days with high data rate on the dayside of the orbit are planned for September 23rd/24th. These measurements will generate scientific nadir/limb data being as useful for validation as in the nominal low rate case.

    Note that between September 8th and 11th, an Orbit Control Manoeuvre (OCM) and the upgrade of the ENVISAT PMC s/w is planned. This requires all instruments to be switched off. The September plans still show measurements throughout this period. Whenever ENVISAT has decided on the exact dates for the OCM and PMC upgrade activities, our plan will be overwritten by the ENVISAT Mission Planning System, i.e. SCIAMACHY declared 'unavailable' for this interval. The switch-on of the instruments after the PMC upgrade requires to start SCIAMACHY as early as possible in order to ensure thermally stable detectors on September 12th/13th.

    Some geolocation maps include the air route of the Falcon north and south campaigns to facilitate matching of SCIAMACHY pixels with potential measurements from the aircraft. Details of the north and south route are listed below.

    North  
    Tuesday, 03 September Oberpfaffenhofen - Kiruna/Sweden
    Wednesday, 04 September Kiruna - Kiruna via Ny Alesund
    Thursday, 05 September Kiruna - Keflavik/Iceland
    Friday, 06 September Keflavik - Sondre Stromfjord/Greenland with turn at 075 West
    Saturday, 07 September Sondre Stromfjord - Keflavik
    Sunday, 08 September Day off (Keflavik)
    Monday, 09 September Keflavik - Liege/Belgium - Oberpfaffenhofen
    South  
    Thursday, 12 September Oberpfaffenhofen - Palma de Mallorca/Spain
    Friday, 13 September Palma de Mallorca - Ghardaia/Algeria - Niamey/Niger -
    Yaounde/Cameroon
    Saturday, 14 September Day off (Yaounde)
    Sunday, 15 September Yaounde - Nairobi/Kenia
    Monday, 16 September Nairobi - Seychelles
    Tuesday, 17 September Day off (Seychelles)
    Wednesday, 18 September Spare Day
    Thursday, 19 September Seychelles - Nairobi
    Friday, 20 September Nairobi press conference
    Saturday, 21 September Nairobi - Yaounde
    Sunday, 22 September Yaounde - Niamey - Ghardaia - Palma de Mallorca
    Monday, 23 September Day off (Palma de Mallorca)
    Tuesday, 24 September Palma de Mallorca - Oberpfaffenhofen



    02 August 2002: Validation measurements started and geolocation update:

    On August 2nd (orbit 2204), SCIAMACHY started again to execute scientific measurements in support of the August validation campaigns. After the end of the preceding non-nominal decontamination no adjustment of thermal parameters was necessary, i.e. also the early measurements are obtained with a thermally stable instrument.

    The associated geolocation files Nadir and Limb have been updated by providing pixel indices per orbit. This facilitates to identify individual pixels, both in the text files and maps. The geolocation coordinates remained of course unchanged.




    24 July 2002: Geolocation Sun and moon occultation:

    Geolocation concerning the line of sight (LOS) during Sun and moon occultations has been provided as geographic latitude of the tangent point at altitudes of 20 km and 100 km as a function of time. Graphic display of the longitude does not yield any useful information as the westward orbital shift of about 25º per orbit results in a longitude coverage of 0º - 360º over a year. Therefore the occultation geolocation information is now supplemented by files listing the full geolocation (geographic longitude and latitude) as a function of orbit number for the SO&C/MO&C LOS tangent point at altitudes of 20 km and 100 km. Additionally the location of the tangent points (altitude 20 km to 100 km) projected onto the Earth map can be accessed.

    The updated occultation geolocation information can be found under Orbit Analysis SO&C window and MO&C window.




    23 July 2002: SCIAMACHY August measurement plan:

    The measurement plan for the time period August 2nd - August 31st (429 orbits) has been generated and delivered to ENVISAT. It assumes continuous quasi-nominal instrument operations in support of the August validation campaigns. Calibration & monitoring orbits (daily, weekly, monthly) are implemented in the same way as required for nominal operations.

    SCIAMACHY's planned August activities can be accessed via the pages OSDF and SDMOP. Predicted geolocation information based on the simulated operations plan is available under Swath Visualization Nadir and Limb.




    17 July 2002: News about geolocation:

    The geolocation files to be found under Nadir and Limb have been updated. The update adds the sub-satellite track to the maps with the illuminated part of the orbit shown in yellow and the eclipse part shown in dark blue. A small s/w bug has also been corrected which caused a slight along-track shift in some of the ground pixels (maximum possible shift in the order of 0.5 deg at the equator).




    16 July 2002: SCIAMACHY is back in MEASUREMENT mode:

    ESOC successfully recovered SCIAMACHY from the previous malfunction. In orbit 1969 (July 16th, 15:32 UTC) the instrument was back in MEASUREMENT IDLE mode. The MPS schedule was picked up there and preparation for the start of the validation phase resumed. Thanks to the quick and efficient recovery performed by ESOC, the planning for the first part of the validation phase will start as planned on July 18th.




    15 July 2002: MCMD CCA check error strikes back:

    After having installed countermeasures to prevent the MCMD CCA check error, which sent us several times to SUSPEND between mid May and mid June, SCIAMACHY experienced about 4 weeks of uninterrupted operations. Now in orbit 1952 (July 15th) this error occurred again causing a switch-off of the instrument. Unfortunately it happened during the 'icing test' which should help to find the thermal operating conditions for the IR detectors to avoid built-up of ice layers. Recovery is ongoing.

    How to proceed with operations is under discussion as on Thursday (July 18th) the first part of the validation measurements has to start.




    09 July 2002: Modified geolocation information:

    The SCIAMACHY limb geolocation information, to be found under Geolocation, has been modified. In order to make the presentation more realistic, there is now only one limb file. The start of the limb ground pixel is determined using the swath control template for Limb Low (tangent altitude = 0 km) of the ESOV tool, the stop is calculated using the Limb High (tangent altitude = 100 km) template. Thus the limb pixel represents an upward scan from the horizon to the top of the atmosphere as implemented in the limb states.
    The resulting limb pixels have a much smaller extent in along track direction. This is due to the fact that the tangent point at high altitudes lies closer to the spacecraft as it moves along the orbit.

    All orbits executed sofar have been re-processed for limb using the modified approach. The same is true for nadir pixels since the new release of ESOV also provided new swath control templates files.




    25 June 2002: Ancillary MCMD spacing and geolocation:

    In order to avoid the MCMD CCA check errors (which sent us several times to SUSPEND recently), the spacing of the Ancillary MCMDs was increased from 1 sec to 4 sec. As the Ancillary MCMDs are used by some states to control the scan mirrors, the increased spacing could lead to a reduced SCIAMACHY pointing performance, i.e. it would mainly impact altitude geolocation information obtained at the Earth limb.

    The change in Ancillary MCMD sent from PMC to ICU became effective on June 18th.




    20 June 2002: SCIAMACHY Elevation Cover released:

    In orbit 1594 the scheduled measurements of the Lunar Measurement window were interrupted for the release of the Elevation Cover. The release was successfully achieved in this orbit at about 10:50 UTC. All telemetry parameters show nominal behaviour.

    First real Nadir measurements are already expected in the Lunar Measurement Window which continued in orbit 1596 and will last until June 26th.




    18 June 2002: SCIAMACHY ..... and on again:

    As announced in the previous news, the common effort of operations brought SCIAMACHY successfully back into measurement at orbit 1571.
    The planned schedule is exactly picked up with repetition of Measurement Window 3 and subsequent Monitoring 6a_2.

    Note: Nadir Cover release is shifted to orbit 1595 on 20.06.2002 (12:01 UTC).




    17 June 2002: SCIAMACHY ..... and off again:

    After having re-established MPS driven operations in orbit 1511, the PMC/ICU interface error sent SCIAMACHY back to SUSPEND in orbit 1550 again. Needless to say that investigations are ongoing.

    ENVISAT and SCIAMACHY undertake every effort to almost maintain the schedule for the elevation cover release. Presently it is planned to proceed with MPS driven measurements in orbit 1571 and to move the elevation cover release by only 1 day to June 20th. A final decision to release the cover will be taken tomorrow (June 19th) at the release review.




    14 June 2002: SCIAMACHY back in SODAP operations:

    The recovery from the last switch-off succeeded on June 14th with bringing SCIAMACHY back to MPS driven operations in orbit 1511. Thus parts of the measurement window 4.1 could still be obtained. Operations so far show almost nominal behaviour. Only a few anomalies were reported which are under investigation.

    At the ARB initiating the recovery, ENVISAT and SCIAMACHY decided to modify several operational procedures to minimise the risk of further PMC/ICU interface errors. These focused around the MCMD traffic between PMC and ICU during CTI MCMD loads. It was decided to

    The first error which occurred on June 12th (transfer to HEATER/REFUSE) was unrelated to the switch-off. It might be attributed to a single event upset caused by radiation in the overcurrent protection chain.




    13 June 2002: SCIAMACHY switched off again:

    Shortly before resuming MPS driven SODAP operations in orbit 1485, SCIAMACHY was first transfered to HEATER/REFUSE mode and in a second anomaly switched off this morning. More details can be found in the text below provided by Astrium:

    Current SCIA Status:

    1. yesterday SCIA safed itself to Heater-Refuse mode. An Out-of-Limit (OOL) was detected "indicating" a 28 Volt overcurrent protection switch was triggered.
    Note: at the time when the safing occurred, there were no loads powered by the 28 Volts line. There is currently no explanation for such an event (??? latch up by radiation ???) There were also no commands (other than Ancillary Data MCMDs) send to the SCIA ICU when the safing occurred and no timeline was running.

    2. This morning the PMC safed SCIA from Heater-Refuse to R/W-Wait mode, i.e. all equipment off and the ICU suspended.
    Reason: PMC - ICU protocoll error (probably same mechanism as for the previous safing to R/W-Wait on 26-May). Seemingly the PMC safing event is not related to the previous OOL-safing. Current activities: dump ICU memory for failure investigation.

    3. Recovery Schedule: TBD




    11 June 2002: SCIAMACHY recovery:

    On June 10th, the recovery of SCIAMACHY from the recent ENVISAT instruments switch-off back to nominal SODAP operations has started. Planning input has been provided to ENVISAT to start MPS driven measurements on June 12th in orbit 1485.

    Details can be found on Astrium' SODAP, OSDF and SDMOP pages.




    06 June 2002: ENVISAT payload safing:

    On June 5th, 21:18 UTC all instruments on ENVISAT were switched off due to a Level 3 Protocol Interrupt. They remain off until further notice.

    The safing occurred about 41 hours after SCIAMACHY had resumed MPS driven operations following the last anomaly on May 26th. The associated orbits 1360-1385 have been used for Thermal Variation measurements.

    Details of the re-planned SODAP sequence will be made available on Astrium' SODAP page.




    26 May 2002: SCIAMACHY switched to RESET/WAIT:

    After successfully resumed MPS driven operations with start orbit 1213 SCIAMACHY performed a series of measurements aiming at execution of special states such as Lunar measurements and Limb measurements with reduced elevation steps.
    In orbit 1238 SCIAMACHY was again suspended by the PMC with same error messages as in orbit 1113. The PMC-PLSOL in orbit 1245 (27.05. at 01:38 UTC) prevents detailed analysis of the SCIA-SOL on the SCIAMACHY side. The present plan is to start recovery of SCIAMACHY on May 29th and restart MPS driven operations with orbit 1360.

    Details of the re-planned SCIAMACHY SODAP sequence can be found on Astrium' SODAP page.




    17 May 2002: SCIAMACHY switched to RESET/WAIT:

    While resuming MPS driven operations after the ENVISAT payload safing, SCIAMACHY was transfered into RESET/WAIT mode on May 17th (orbit 1113). The cause seems to have been a communication problem between the ENVISAT Payload Module Computer (PMC) and the SCIAMACHY Instrument Control Unit (ICU). Error analysis has started. Currently the modified plan expects that SCIAMACHY starts with SODAP measurements on May 24th in orbit 1213.

    Details of the re-planned SCIAMACHY SODAP sequence can be found on Astrium' SODAP page.




    13 May 2002: SCIAMACHY recovery started:

    After the switch-off of the instruments caused by ENVISAT's payload safing, the recovery of SCIAMACHY back to MEASUREMENT mode has started. It is envisaged to begin MPS driven measurements on May 17th (orbit 1113). The modified SODAP plan now lists the thermal window activities prior to the start of lunar window 2. All remaining measurement window 4 operations will be scheduled after the lunar window. The release of the Elevation Cover requires only a short delay up to June 3rd.

    Details of the re-planned SCIAMACHY SODAP sequence can be found on Astrium' SODAP page.




    11 May 2002: ENVISAT payload safing:

    Caused by an ENVISAT PMC anomaly, all instruments - including SCIAMACHY - were switched off. This occurred May 11th at 12:54 UTC (orbit 1022) just before the end of Measurement Window 3. The already planned measurements for Monitoring 5_2 and the activities of the Thermal Variation re-run could not be executed.

    As soon as recovery details are available, they will be reported here.




    03 May 2002: SCIAMACHY 'sub-solar mystery' explained:

    SCIAMACHY's unsuccessful attempts to detect the Sun through the sub-solar window since orbit 525 can now be explained. During these early measurements the Ka-band antenna of ENVISAT was stowed in front of the sub-solar window thus obscuring its TCFoV. After the antenna had been moved to its specified parking position, the sub-solar Sun signal reached the detectors as planned. Therefore this anomaly is considered to be no longer existent.

    Note that the design of the SCIAMACHY and ENVISAT mission planning systems usually prevent Ka-band antenna interference during sub-solar measurements.




    28-30 April 2002: SCIAMACHY in HEATER/REFUSE mode:

    On April 28th, 22:01 UTC (orbit 842), SCIAMACHY was unexpectedly transfered into HEATER/REFUSE mode. The cause of this event is unknown. Analysis of the anomaly and its impact on SODAP execution (the event occurred during the Thermal Variation window) has led to a recovery back to the nominal schedule on April 30th, 17:36 UTC (orbit 868).

    Currently SCIAMACHY investigates how to re-schedule the lost thermal variations tests. Details of the anomaly event and the recovery activities can be found in the summary below, taken from an e-mail message from Astrium.

    The SCIA PMTC switched unexpectedly to DUMP mode 28-April 22:02 UTC. This was detected by the ICU limit checking and a corrective action CA-1 was triggered which transfered SCIA to Heater-Refuse mode. From here on all Start Timeline MCMDs were rejected.

    At the time when the PMTC switched to DUMP mode, SCIA was in Measurement-Idle mode, no commands were executing, no timeline was running. The reason for this transition to DUMP mode is still unknown.

    On April 29 and 30 there were various PMTC RAM dumps commanded. The data of 2 of these dumps (the fixed area of the RAM) were received and analysed. There was no indication for an SEU or any other anomaly found in the dumped areas. It was also confirmed that SCIA was outside the SAA when the safing occurred. During an ARB with ESOC and DLR it was decided to go ahead with the instrument recovery.

    On 30-April at 15:44 UTC recovery back to Heater mode was commanded. The commanding was done such that the load of the AP SW from EEPROM to RAM was inhibited, so that the Secondary Processor Initialisation would run from the RAM, as it was frozen at the time of safing. By this we were hoping to learn more about the cause of the original safing event. This procedure applied to the PMTC and the SDPU, because the command being readily available for execution addresses both SPs, the PMTC and the SDPU. During the recovery transition back to Heater mode the SDPU (when starting from its frozen RAM contents) produced an error message to the ICU which triggered another corrective action CA-2. The CA-2 transfered SCIA to Stanbby-Refuse-I mode, with power being removed from the PMTC and the SDPU. This was obviously unexpected and it also destroyed our hope to get more information out of the PMTC RAM, because power was removed by now.

    The good news is that the PMTC had already successfully (!) exercised ist selftests before the SDPU caused the safing, indicating that there was not a major hardware problem with the PMTC.

    Investigations habe been started to understand why the SDPU produced an error message when being initialised from the RAM. Nevertheless it was assumed that this had nothing to do with the original failure we tried to analyse.

    During an ARB with ESOC and DLR we decided to recover back to Heater mode during the next pass at 17:22 UTC. The recovery went well and timelines from the original MPS schedule (still on board) started executing. During the following pass time tagged commands have been uplinked in order to pick up the remaing two parts of the Thermal Variation tests TVA_3 and TVA_4, starting at 22:27 UTC on the same day. Up till now the instrument seems to work nominal.

    Immediate consequences concerning the SODAP schedule are as follows

    1. SCIA now follows the original schedule starting on 30-April at 22:27 UTC
    2. the original schedule will be followed up to and including the Measurement Window 3 and Monitoring 5_2, which ends on 11-May at 16:20 UTC.
    3. the Thermal Variation tests TVA_1 and TVA_2 must be rerun before starting Measurement Windows 4.x

    Details concerning the new schedule after 11-May at 16:20 UTC are not yet available.




    24 April 2002: Kiruna coverage parameters available:

    For the orbit interval covered by the first ROE file, the Kiruna coverage parameters of ENVISAT passes with a start/stop elevation of 5° are now provided under the topic 'Orbit Analysis'. The parameters have been derived by using the ENVISAT CFI s/w. They are based on the reference orbit.




    23 April 2002: Swath Visualization file access available:

    Starting with orbit 513 the SCIAMACHY swath visualization files are now available for those orbits where nadir (incl. nadir_eclipse) or limb states are planned. The files exist as maps (gif-files) or text files (ASCII). Each time a SDMOP or SIM_SDMOP has been derived, the visualization files are generated in batch mode and added to the web page, organised in slices of 100 orbits each.




    15 April 2002: Successful opening of SRC door:

    In orbit 653 (15 April 2002) at 17:01 UTC the SRC door was successfully released. Telemetry parameters show nominal behaviour. With a fully functioning SRC it will now be possible to execute measurements with cold detectors. They are scheduled to start at orbit 691 (18 April 2002).




    13/14 April 2002: SCIAMACHY anomaly causes brief interrupt of operations:

    At the end of orbit 627 (13 April 2002, 22:39 UTC) SCIAMACHY was automatically transferred to STANDBY/REFUSE-I mode. This was caused by the SRC Cold Stage Temperature parameter exceeding its upper limit for nominal measurement conditions. The instrument was brought back to HEATER mode in orbit 634 (14 April 2002, 09:11 UTC). Planned operations commenced end of orbit 634.




    5 April 2002: First 'real' Sun and limb measurements in Measurement Window 2:

    With the successful release of the Azimuth cover in orbit 447 it is now possible to observe the Earth horizon, either for Sun/moon or limb measurents. In Measurement Window 2 (MW2), which started at orbit 506 (5-April 2002), the Sun was observed for the first time. In the same period, limb measurements were commanded. The operations in MW2 performed without any major problems. Although the instrument was commanded to execute rather complex operations of the scanner (e.g. for Sun Follower checkout), only a few minor warnings were issued and SCIAMACHY continued the scheduled measurement programme. A first data analysis indicates that the limb and solar states worked as expected.

    The two figures below show uncalibrated limb and Sun spectra from channel 4, derived at IFE. Atmospheric absorptions (limb) and Fraunhofer lines (Sun) can be clearly seen.

    Raw limb spectra in channel 4 for a sequence
    of vertical scan steps
    Raw Sun-over-Diffuser spectrum in channel 4




    3 April 2002: Successful opening of azimuth cover:

    In orbit 477 at 10:09 UTC the azimuth cover of SCIAMACHY was successfully released! All telemetry parameters show nominal behaviour. The first measurements through this window are planned for orbit 506 (5-April-2002, 10:23 UTC) when the Sun will be observed during Sunrise at an altitude of 100 km.




    22 March 2002: LLI prediction started and SAA flag in ROE Excerpt

    The predicted use of the Life Limited Items is now provided on the LLI status page for the first executed measurements. This prediction is based on the planned operation of timelines in the associated OSDfs. Whether the operations have been implemented as planned can be derived from the corresponding reports on the SODAP_Astrium page.

    In order to estimate potential impacts of the South Atlantic Anomaly (SAA) on instrument operations, a SAA flag has been added to the ROE Excerpt file. This flag indicates a passage of ENVISAT through the SAA on the ascending (SAA - eclipse) or descending part (SAA - day) of the orbit.




    17 March 2002: First MPS driven timeline operations:

    In orbits 238-240 SCIAMACHY timelines were for the first time operated under MPS control. Orbit 238 started with the timeline for the Full Functional Test, orbit 239 commenced with two consecutive Special Test timelines in high data rate and orbit 240 finished with a monitoring timeline. Except of two states in the Special Test timelines no anomalies occured. Preliminary analysis of the available data suggest that the goals of the three orbits were successfully achieved. Planning details can be found on the OSDF and SDMOP page.

    SCIAMACHY FFT timeline in orbit 238: sequence of states
    as derived with SOST Timeline Scheduler and DMOP tool,
    displayed with ESA ESOV tool



    15 March 2002: First successful measurements of on-board light sources performed:

    During orbit 197 the SCIAMACHY on-board light sources (White Light Source - WLS, Spectral Light Source - SLS) were switched on successfully and the first spectra of the on-board light sources were recorded and transmitted to ground. A preliminary analysis of the data indicates that the SCIAMACHY spectrometer behaves nominal in orbit.




    12 March 2002: Successful SCIAMACHY switch-on and updated SCIAMACHY SODAP overview:

    SCIAMACHY has been successfully switched on in orbits 147-155 (11 March 2002)! Details can be found in the Plan_Overview of the SODAP_Astrium page. This overview also reflects the most recent changes of the ENVISAT System SODAP plan has been updated. The update includes a time interval reserved for ENVISAT PMC s/w patch upload which has been already identified prior to launch. As a result the SCIAMACHY activities after the opening of the azimuth cover are shifted in time.




    06 March 2002: First 'real' mission planning information - ROE Excerpt & SODAP Plans:

    After the successful launch of ENVISAT March 1st, the mission is running as planned. SOST has now received the first Reference Orbit Event and Sub-solar Calibration Opportunity file. The corresponding ROE Excerpt has been derived and can be found on the associated page. It covers the time interval from orbit 1 to 1557. Also 'Plan Overview' on the SODAP_Astrium page has been updated accordingly.




    25 February 2002: Test Reference Orbit Event File Excerpt:

    For the purpose to become familiar with one of the basic planning files during the mission, the excerpt from the ROE file, a test excerpt can be found under 'ROE files excerpt'. Do not use the time-tags provided therein for your detailed planning as several assumptions (e.g. time of launch, injection into orbit) were made at generation of this file. The 'real' ROE excerpt is expected at about L+1 week.




    25 February 2002: SCIAMACHY SODAP details:

    A chapter has been added which provides specific information about SCIAMACHY operations planning in SODAP and provides the link to the web page with SODAP plans and reports maintained by Astrium-SCIA. This page is also located on the DLR atmos server but controlled remotely by Astrium-SCIA.




    20 February 2002: SCIAMACHY SODAP overview:

    Note: The most actual SCIAMACHY SODAP plan can always be found on the SODAP_Astrium page.



    20 February 2002: SOST goes online:

    The web-pages of the SCIAMACHY Operations Support can now be accessed. These pages provide instrument status information and the concepts behind SCIAMACHY operations and mission planning. Primarily intended to help the SCIAMACHY user to better understand the measurements, the pages may also be used by operations personnel for quick reference information.

    First time-tagged SCIAMACHY planning details is expected to be available about 1 week after launch.



    Page generated 20 February 2002; last update: 30 April 2016