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
02 July 2010: Next orbit control manoeuvre
17 June 2010: New final flight configuration
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
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
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: 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
20 June 2008: SOST website modification
16 June 2008: Next orbit control manoeuvre
21 April 2008: Next orbit control manoeuvre
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 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: Subsolar window currently obscured
21 May 2007: Short unplanned MEASUREMENT IDLE phase
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
12 May 2005: Transfer to R/W WAIT
10 May 2005: Back in MEASUREMENT
09 May 2005: Transfer to HTR/RF and recovery
08 April 2005: Instrument availability display added in operations summary
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
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
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.
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).
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).
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.
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.
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.
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.
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.
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.
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).
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.
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.
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).
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.
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.
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).
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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).
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.
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.
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.
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).
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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).
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.
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.
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.
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).
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.
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.
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.
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).
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.
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).
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.
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.
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.
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.
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.
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.
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).
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).
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.
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).
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).
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.
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.
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).
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.
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.
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).
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).
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.
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).
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.
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.
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.
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.
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).
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.
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).
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.
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).
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.
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.
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.
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.
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).
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).
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).
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.
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.
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.
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.
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.
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.
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 .
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.
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.
In the next weeks the SOST website will be modified to better handle the extended mission duration. Changes include:
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.
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).
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.
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).
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.
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.
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.
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).
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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).
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.
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.
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.
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).
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.
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.
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.
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.
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).
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.
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.
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.
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.
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.
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.
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.
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.
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.
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).
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.
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.
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).
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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).
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).
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.
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).
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.
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.
The SOST pages have now been moved to a new webserver. The
new server address is
/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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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).
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.
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.
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).
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.
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.
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.
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.
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.
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.
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.
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.
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.
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).
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.
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).
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.
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.
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.
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.
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.
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.
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.
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).
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.
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.
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.
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.
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.
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. |
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.
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.
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.
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.
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.
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).
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.
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).
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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. |
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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) |
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.
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.
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.
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.
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).
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.
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.
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.
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.
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.
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.
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. |
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.
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.
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.
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.
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.
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.
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).
SOST has now implemented in the ENVISAT ground segment all timelines required for the execution of the following mission scenarios:
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.
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.
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).
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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).
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.
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.
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.
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.
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).
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.
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.
We have included now monitoring information on the SOST webpage. This information covers various aspects of
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.
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.
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.
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.
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.
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.
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 |
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.
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.
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.
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.
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.
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.
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.
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).
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.
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.
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.
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.
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.
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.
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.
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.
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. |
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.
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.
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.
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.
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).
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.
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.
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.
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.
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).
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) |
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).
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).
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 |
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.
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.
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.
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).
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.
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.
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.
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.
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.
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).
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.
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.
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
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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).
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.
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 |
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.
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.
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 |
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.
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.
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.
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.
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.
Note: The most actual SCIAMACHY SODAP plan can
always be found on the SODAP_Astrium page.
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.