13 June 2024 - Mission Day: 10422 - DOY: 165
Science Operations


1. Boundary conditions

a) Orbit, attitude and manoeuvres

- SOHO is right side up (0 degrees).

- manoeuvres

  To the degree possible, manoeuvres take place during the last days of
  34-m keyholes.  Currently proposed or set manoeuvre dates are:

  Nov 7            station-keeping, momentum management and 
                   roll (to approximately 180 degrees)

  Feb 2 (TBC)      station-keeping and momentum management

  Feb 5 (TBC)      roll (to approximately 0 degrees)

b) Communications with the spacecraft

  Graphical DSN schedule: http://soho.nascom.nasa.gov/soc/dsn/

  The SOHO High-Gain Antenna (HGA) was moved on Aug 14, 2009 the change the
  Z-axis angle from -18.55 to -16.7 degrees (to reduce keyhole
  durations). The keyhole durations will be shortened by 6-7 days for the
  short keyholes (summer and winter seasons) and 10-12 days for the long

  Keyhole dates for the next 6 months for the old HGA Z-axis angle of
  -18.55 degrees:

* Oct 27-Nov 13 26m Keyhole
* Oct 31-Nov 9  34m Keyhole

* Jan 16-Feb 12 26m Keyhole
* Jan 23-Feb 5  34m Keyhole

  DRAFT Keyhole dates for the next 6 months for the new HGA Z-axis angle of
  -16.7 degrees (these will be confirmed after testing during the
  "mini-keyhole" period peaking on Sep 26, 2009):

* Oct 30-Nov 10 26m Keyhole
* Nov 1-7       34m Keyhole

* Jan 21-Feb 7  26m Keyhole
* Jan 26-Feb 3  34m Keyhole

  All keyhole information is available at or via

- End-of-pass handling during MDI continuous contact periods

  To avoid problems with transmitter masks at the end of passes during MDI
  continuous, DSN has requested we bring the carrier down 30 min before the
  end of pass.  As a result, the last 30 min of all MDI continuous contacts
  will be TM only.  For ranging passes, the spacecraft will be transitioned
  to record ~1 h before the end of the pass.  The station will drop the
  carrier and re-sweep into receiver 2.  The spacecraft will then be
  transitioned back to VC2 and VC3.

- DSN 26 m antenna decommissioning and the keyholes

  DSN decommissioned its 26 m antennae in early August. On 14 August, the
  SOHO HGA Z-axis was successfully moved from -18.55 to -16.7 degrees to 
  reduce keyhole durations.

c) KNOWN submode (SM) dependent activities/submode changes:

* TOO           JOP153/MMOP003 Future Major Flare Watch (SM5 if SUMER
                observes target, SM6 otherwise)
* Oct 8, 15     EIT shutterless #37 (time TBC)
* Jan 7, 15     EIT shutterless #38 (time TBC)

  SUMER campaign dates may overlap with keyholes. Such overlaps shall be
  scheduled only if periods of no SUMER data between passes are acceptable.

  Except for Major Flare Watches, TRACE will be doing full disk mosaics
  if/when EIT is not able to do synoptic sets due to keyhole operations.

d) Instrument maintenance activities

  EIT bakeouts will take place during keyholes. 

e) Spacecraft maintenance activities

  Since the FOT staffing (and hence the FOT's resources to implement
  changes quickly) will decrease towards the end of this calendar year, all
  instrument teams are reminded to review not only thermal, but also other
  limits as well as TSTOL procedures and scripts for possible changes.

  The available power from the solar arrays is decreasing. Currently we
  still have sufficient margin, but in the future the decrease per year
  (now ca. 1 A) may increase to 3 A per year.  We have to be prepared to
  reduce our power needs as much as possible. On the spacecraft side
  several adjustments have already been made and there is not much more
  that can be done.  Therefore we are asking the instrument teams,
  especially the 'big' power consumers LASCO/EIT, CDS, UVCS and SUMER, to
  start looking into ways of reducing their power consumption
  (e.g. different operating modes, heater reductions, ...).  Hopefully we
  will not have to use this reduced power mode very soon, but it is better
  to be prepared in case a power reduction is needed.  More details coming

  The SOHO High-Gain Antenna (HGA) was moved on Aug 14, 2009 the change the
  Z-axis angle from -18.55 to -16.7 degrees.

f) Others

  TRACE eclipse season began on 13 Sep 2008 and will be ongoing, except for
  the following predicted non-eclipse period in 2009:

  Jul 28 -- Sep 9

  Hard eclipses will start on Sept 13

  TRACE' Sep 30 - early Dec hibernation period has been cancelled. The
  entries to this period have been removed from section 2 below.

  Daytime weekday passes of Mon-Wed are currently automated but
  attended. Thu-Fri passes remain crewed for training and proficiency
  reasons. Date of transition to unattended daytime automation remains TBD.

  NRT during automated passes (both weekend and weekday) is currently
  paused (briefly) regularly for resets of software anomalies. NRT schedule
  (which includes the pauses) for all automated passes can be found at

  A (MDI) jitter test completed successfully on July 20.  Data analysis
  will be done and another test may be scheduled in October or whenever it
  is requested by the SOHO ESA engineers. The timing will be coordinated
  around the MDI science roll and the Themis campaign.

  New intermittent recording patch subsets needed during the Bogart mission
  phase will need to be tested on-board, which results in MDI data
  gaps. The testing is suggested to be made after Solar Dynamics
  Observatory (SDO) has been launched successfully.

  MDI Jitter test analysis not yet complete.  However, other jitter
  tests can be scheduled whenever the ESA engineers request them.

2. Priorities for the coming month and more

a) Joint observing plans and campaigns

Continuing campaigns:

* 2002/02/25--  JOP136 Default RHESSI Collaborations (#6850),
                POC: Tero Siili
* 2003/05/13--  Default CDS Co-observations with TRACE (#6950)
* 2005/09/20--  JOP153/MMOP003 Future Major Flare Watch (#8008)
* 2007/03/20--  Default CDS/Hinode-EIS co-observations (#7200)

  Campaign #6850 is for "individual instrument studies" selecting an active
  region target [partially] influenced by the Max Millennium target
  selection to maximise chances of serendipitous co-observations.

  EIT supports all with half/full-res 195 A CME watch in submode 5/6. It is
  clear that STEREO-EUVI provides adequate "context" information for RHESSI
  flare observations. Routine EIT submode and resolution switches are
  probably no longer needed.

* Mar 16 - Sep  LASCO C2pB for Tomography Reconstruction,
                  POC: Angelos Vourlidas, Richard Frazin

* Mar 27-       JOP 222 (ToO) Detecting the Origin of Shock-Accelerated Solar
                  Energetic Particles, LASCO/STEREO-SECCHI
                  POC: Angelos Vourlidas

  LASCO is ready to run the JOP, awaiting a target.

* Sep 14        HERSCHEL sounding rocket launch, 17:40 UT,
                  POC: Dan Moses, Lucia Abbo

  HERSCHEL has been assigned a new launch date on the official WSMR 
  schedule: 14 September 2009.  The tentative T-time is 17:40 UT 
  with the launch window closing at T+20 minutes.  Hopefully the 
  previously requested co-observation plans of 20-21 July can be 
  accommodated on 14 September.

  Description of the payload can be found for instance in the June 2009
  SOHO SPG final minutes
  (http://sohowww.nascom.nasa.gov/operations/SPWG/spwg-20090619.html). See
  also section 2b (intercalibration activities) for proposed
  SOHO/STEREO/TRACE/HERSCHEL cross-calibration (ICAL14).

  UVCS will support.

  EIT and LASCO will support.

  TRACE will support.

* Sep 23-Oct 10 Coordinated campaign with THEMIS,
                  CDS/EIT/MDI/Hinode-EIS/Hinode-SOT (TBC),
                  POC: Brigitte Schmieder

  Coordinated observations between SOHO instruments during observations at
  the THEMIS vector magnetograph are proposed. JOPs 157 and 178 are the
  proposed observing programs, but the descriptions will need to be
  updated. At least CDS, EIT and SUMER are mentioned in the current JOP

  Timing remains TBC.

  MDI has been in touch with the POC re: supporting with full-disk
  observations. Full-disk magnetograms seem to be sufficient, but it may be
  possible after Sep 30 to do High Resolution observations if the JOP's
  require MDI to do so.

  MDI will support this campaign.  There is a request to do Helioseismology
  with Hinode at the beginning of Sep.  Most of Sep is reserved to do full
  disk Helioseismology, but MDI needs to have 3 periods of 16 h of
  uninterrupted MDI high rate data.  The preferred dates are Sep 3-11, but
  they need not be contiguous. Request for the high rate periods has been
  submitted to the DSN scheduler. See also the MDI Continuous Contact entry

  CDS will support.

* Sep 25-27      MDI Continuous Contact, MDI

  Will do full disk, 1 minute cadence Magnetograms and Dopplergrams along
  with the usual 96 minute synoptic Magnetograms and Continuum images (when
  in MDI high rate).

* Sep 27-Oct 25  JOP 224 Solar Tomography with Minimal Solar Rotation,
                   POC: Russ Hewett

  Proposed STEREO-SOHO co-observations. A unique configuration of the three
  spacecraft is utilized and dictates the timing, but details and timing
  remain TBC.  The optimal configuration occurs on 11 Oct. Draft
  description can be found at

* Oct 8 (TBD)   EIT shutterless #37 run 1,
                  POC: Susanna Parenti

* Oct 15 (TBD)  EIT shutterless #37 run 2,
                  POC: Susanna Parenti

* Oct 26 (TBD)  MDI science roll, MDI/CDS/SUMER (TBC)

  A 360-degree roll with multiple stops and observations is being planned
  and Oct 26 seems to be a good candidate date. The timing remains TBD,
  however (and can in principle also be during the keyhole). DSN 70-m
  support will be needed. The duration of the maneuver is TBD, but is
  expected to be of the order of 6-12 h. The Earth-SOHO distance, DSN
  availability (including keyhole) and the proposed JOP 224 are among the
  timing constraints.

  Information on a similar earlier maneuver can be found at
  http://sohowww.nascom.nasa.gov/soc/timeline_roll2001 and
  http://sohowww.nascom.nasa.gov/soc/timeline_roll2001.detailed. The
  details (such as number of stops and dwell times) will most likely be
  different this time.

  Other instruments are invited to take advantage of this maneuver.

  CDS will use the multiple stops during the roll to verify the instrument
  point spread function.

  SUMER would like to participate but will not be able to if the roll is 
  Oct 26 or 27. 

  MDI says the roll does need to be completed in a single day, I don't 
  think we can have any appreciable gap in contacts during the roll.

  Resolution from Tina Kelly:
  Here are the times scheduled for the 26th and 10th (backup day).

  October 26
  299 1305 1350 2350 0005  DSS-27  SOHO   ROLL MNVR MDI UL 0299  N056  V 1A1  
  299 1320 1350 2350 0005  DSS-14  SOHO   ROLL MNVR MDI DL 0299  N073  I 1A1

  November 10
  314 1450 1535 0045 0100  DSS-27  SOHO   ROLL MNVR MDI UL 0314  N056  V 1A1
  314 1505 1535 0045 0100  DSS-14  SOHO   ROLL MNVR MDI DL 0314  N162  I 1A1

* Jan 7 (TBD)   EIT shutterless #38 run 1,
                  POC: Susanna Parenti

* Jan 15 (TBD)  EIT shutterless #38 run 2,
                  POC: Susanna Parenti

b) Intercalibration activities

  Last ICAL was: August 20

  ICALs are normally performed monthly. Below is a SOC proposal for ICAL
  weeks for the next six months. Baseline will be to schedule it for
  Thursday during contact.

* Sep 14 (TBC)  ICAL14 SOHO-STEREO-TRACE-HERSCHEL radiometric 
                  cross-calibration (TBC),
                  POC: Lucia Abbo

  A radiometric cross-calibration between SOHO, STEREO, TRACE and the
  HERSCHEL sounding rocket has been proposed. A preliminary draft of the
  ICAL proposal can be found at
  http://sohowww.nascom.nasa.gov/soc/JOPs/ical014-draft.pdf. For timing and
  details of the HERSCHEL launch see section 2a above.

* Sep 14-18     ICAL01 (#7113), CDS/EIT/STEREO/Hinode-EIS(TBD)/Hinode-SOT(TBD)

  The proposed ICAL14 intercalibration (see above) needs to be taken into
  account in scheduling the ICAL01 for this week.

* Oct 12-16     ICAL01 (#7113), CDS/EIT/STEREO/Hinode-EIS(TBD)/Hinode-SOT(TBD)

* Nov 16-20     ICAL01 (#7113), CDS/EIT/STEREO/Hinode-EIS(TBD)/Hinode-SOT(TBD)

* Dec 14-18     ICAL01 (#7113), CDS/EIT/STEREO/Hinode-EIS(TBD)/Hinode-SOT(TBD)

* Jan 11-15     ICAL01 (#7113), CDS/EIT/STEREO/Hinode-EIS(TBD)/Hinode-SOT(TBD)

* Feb 15-19     ICAL01 (#7113), CDS/EIT/STEREO/Hinode-EIS(TBD)/Hinode-SOT(TBD)
  Proposed compiled ICAL scheduling criteria, constraints and guidelines
  (see also campaign #7113):

  1) EIT/CDS are the primary participating instruments

  2) STEREO-EUVI observations are included when possible. ICALs are
     attempted to be scheduled not to coincide with STEREO manoeuvres or
     other interruptions in observations (see

  3) EIT: ICALs OK at all other times except the weeks of shutterless

  4) Dates, details and confirmation will be determined by the planners
     with support from the SOHO SOCs.

  5) Neither Hinode-SOT nor Hinode-XRT have current interest in
     participating in ICALs. Hinode-EIS will from time-to-time perform its
     sensitivity calibration exercise, but has no need to perform this
     regularly as part of the SOHO ICAL. When it is convenient for
     Hinode-EIS (given Hinode's constraints), SOHO will be informed ahead
     of time of when the sensitivity calibration is to be performed. It
     will then be up to SOHO whether to follow Hinode-EIS' pointing and

  CDS OK. If Hinode-EIS can suggest convenient date & time, CDS can usually

c) Individual instrument plans


  See section 2a for MDI continuous contact periods.

  MDI may reduce the ALT cadence during Keyholes to be less than 15 ALT
  magnetograms per day if the lack of high rate telemetry is such that we
  will lose all or almost all of the 15 ALT Magnetograms each day.  The ALT
  cadence will be decided on an individual Keyhole basis and even a daily
  basis during each Keyhole depending on the 70 m antenna availability at
  the time.  MDI may also down-link select magnetograms in the 5 kbps
  telemetry if no 70 m passes are available at least every 2 days for Mag
  dump in the 160 kbps telemetry.

  All requests for MDI support need to be made several months ahead of time
  and sent to mdi-ops(at)mdisas.nascom.nasa.gov.  Even outside keyholes,
  MDI can only do 1-minute cadence observations when we have contact and
  there is no recorder dump in progress.

  MDI's REQUEST page is at http://mdisas.nascom.nasa.gov/coordination.txt
  NOTE: Listing of a study on that page means *only* that a request has
  been received, not that it will necessarily be supported.

  A description of MDI Observing Modes most used for JOPs and campaigns (FD
  vs. HR) can be found at http://mdisas.nascom.nasa.gov/Collaborate.
  Anyone requesting MDI observations is encouraged to read this page in
  order to have a better idea of what observing modes would be best suited
  for a particular study.  More detailed information about how MDI
  operates, observational constraints and telemetry information can be
  found at http://mdisas.nascom.nasa.gov/MDI_Collaboration_Details.

  MDI has switched to Focus 5 (best focus for full-disk observing) on Oct
  23, 2008.

  MDI will do Full Disk Velocity observations for March and September 2009.
  These FD Velocity observations are reserved specifically to collaborate
  with Hinode-SOT.  MDI also reserves the March (28-30) continuous contact
  for FD Helioseimology studies with Hinode-SOT.

  A 360-degree roll with multiple stops and observations is being planned
  --- see October entries of section 2a above.

  A jitter test was done on Jul 20. See also section 1f.


  For weekly plans, see the SOHO calendar and the UVCS planning page:


  For details see http://solar.bnsc.rl.ac.uk/scientificops/request.shtml.


  EIT: 195 A CME watch plus synoptics at 6-hour cadence, as usual. Full-res
  CME watch whenever we're in submode 6. Hope never to change until the
  Bogart mission.


  SUMER would like to participate in the roll manoeuvre (see also section
  2a) but will not participate if it is Oct 26 or 27. We have a problem with 
  our remaining detector (with the potential of being a serious one) and would 
  like to do some tests before we discuss further science observations. We 
  suggest to do this test after the November keyhole.

  SUMER has plans for another campaign after SDO commissioning. Dates are
  still TBD.


  NOTE that TRACE in general reserves the right to withdraw support from
  agreed, existing collaborations if a sufficiently "good active region" is
  called by the Max Millennium group.

  For TRACE summer eclipse season see section 1f.

3. Any other business

* Tentative SPWG meeting times for next six months (only the next one will
  be decided in this meeting). Meetings take place as a baseline on Fridays
  after the daily and weekly meetings.

  Sep 25
  Oct 30
  Nov 20
  Dec 18
  Jan 29
  Feb 26

The rest are FYI items:

* In the future SOHO's DSN contacts will grow shorter as we lose 26-m
  antenna support and other, new missions get higher priority. The
  instrument teams are therefore requested to look at the NRT commanding
  that is done (especially for emergencies and recoveries) and see what can
  be converted into TSTOLs that the FOT can run (even without explicit
  instrument or SOC direction).

* MDI high-rate support requests: no change, see URL

* DSN support requests: preferably at least 6 months in advance.  Keep this
  in mind for: ground-based collaborations that require MDI support,
  stellar/shutterless observations that require NRT, etc.

* Future Mercury and Venus transits: no change, see URL

* Hinode operational and planning information and guidelines: no change,
  see URL http://sohowww.nascom.nasa.gov/operations/SPWG/spwg-20080118.html
  and http://sohowww.nascom.nasa.gov/soc/JOPs/jop-submit.html

* STEREO operational and planning information: no change, see URL

* The SOHO JOP/ICAL database and the web pages are now the Solar JOP/ICAL
  database and web pages. This is due to anticipated increased
  contributions by and collaborations as well as intercalibrations with
  STEREO and Hinode.

* New JOP vs. modified existing JOP rules-of-thumb: no change, see URL

* SOHO calendar email notifications: no change, see URL

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