21 June 2024 - Mission Day: 10430 - DOY: 173
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:

  May 12 (TBC) station-keeping, momentum management, roll (to approximately
  180 degrees)

  Aug 11 (TBC) station-keeping and momentum management
  Aug 13 (TBC) roll (to approximately 0 degrees)

b) Communications with the spacecraft

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

  Keyhole dates for the next 6 months (All keyhole information is available
  at or via http://soho.nascom.nasa.gov/soc/keyholes.html):

* Apr 28-May 16 26m Keyhole 
* May 02-12     34m Keyhole

* Jul 22-Aug 20 26m Keyhole 
* Jul 29-Aug 13 34m Keyhole

- 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 is in the process of decommissioning its 26 m antennae --- the only
  one left is DSS-46. DSS-46 is planned to be decommissioned Oct 31,
  2009. DSS-46 may, however, be decommissioned as early as Aug 3,
  2009. Since the current high-gain antenna (HGA) position along the
  unmoved axis has been optimized for 26 m antennas, the spacecraft team is
  investigating moving the HGA to a position optimized for 34 m
  antennae. Such a change would shorten or remove the keyholes, but DSN
  resource allocation issues and possible impacts on MDI and MDI/SDO-HMI
  cross-calibration period need to be addressed. For analyses and details
  see the minutes of Science Working Team meeting number 40 (available at
  http://sohowww.nascom.nasa.gov/operations/SWT/Minutes/swt40.pdf, pages

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

* TOO           JOP153/MMOP003 Future Major Flare Watch (SM5 if SUMER
                observes target, SM6 otherwise)
* Apr 1		EIT Shutterless #35 (SM6)
* Apr 15-29     SUMER campaign (SM5)
* Jun 1-Jul 10  Sunrise 5-day balloon flight

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

  SUMER preparatory and campaign ending activities related to the Apr 15-29
  campaign are proposed to be scheduled as follows:

  Submode change 6->5 on Apr 13 at 13:30 UT (TBC).
  Door opening on Apr 14.
  SUMER operational on Apr 15.
  Door closing late on Apr 30.
  Submode change 5->6 on May 1 at 15:00 UT (TBC).

  SUMER will observe during the Sunrise balloon flight. Note, that the
  balloon launch is scheduled for Jun 1 - Jul 5 and the duration is
  expected to be 5 days. For submode change plan see the Sunrise entry in
  section 2a below.

  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 bake-out periods will be during keyholes. The bake-out period during
  the Feb 2009 keyhole took place Feb 7-13.

e) Spacecraft maintenance activities

  Reduction of PLM heaters was successfully completed.

  Jean-Philippe Olive is in the process of contacting all teams about the
  instruments' heaters. This relates to future optimization of thermal
  control and electric power supply.

  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.

f) Others

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

  Mar 7 -- Apr 29
  Jul 28 -- Sep 9

  TRACE will not perform science operations from May 15 - July 12, and
  from September 30 through early December.

  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

  The development of a software anomaly detection system (which would pause
  NRT only when needed instead of the current regular pauses) has been put
  on hold due to problems in development.

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

* Mar 28-30     MDI Continuous Contact

  Note "End-of-pass handling during MDI continuous contact periods" in
  section 1b.

  Default observation program is full-disk, 1-min cadence magnetograms and

* Mar 29        Daylight Savings Time begins in European Union at 01 UT

* Apr 1         EIT shutterless #35, EIT/CDS/MDI/TRACE/STEREO,
                  POC: Susanna Parenti

  Runtime is 16-19 UT.

  MDI will support with full disk, 1-min cadence magnetograms and

  This shutterless will be part of and support JOP 216/HOP 98.

  CDS ok, however, the CDS sequence is designed to support JOP 216. 

  TRACE will support.

* Apr 1         JOP 216/HOP 98 Multi-wavelength Observations of Oscillations
                  in Polar Plumes (#7296),
                  CDS/EIT/Hinode-EIS/Hinode-SOT/Hinode-XRT/STEREO/TRACE (all TBC)
                  POC: James McLaughlin

  See also the EIT shutterless #35 entry above

  TRACE will support.

  Inputs from the JOP POC:

  * All instrument teams contacted and informed of the new date for the
    repeat run (1 April rather than 27 Feb)
  * Data from the first run (27 Feb) checked, leading to no changes in
    specific requirements for CDS, EIS, SOT, XRT and STEREO. TRACE team
    working on a new program to generate longer sequences of
    30-second-cadence images (i.e. improving data from first run).
  * Target South Pole. James McLaughlin will email target coordinates
    to EIS and CDS on Sunday 29 March.
  * Timing of High Cadence, 12-14 UT on Wednesday 1 April 2009 for the
    observations by XRT, SOT, EIS, CDS, STEREO/EUVI and TRACE. The EIT
    observations will then occur later that day (16-19 UT).

* Apr 15-29     SUMER-Hinode Campaign,
                  POC: Davina Innes

  The campaign dates have been confirmed by the Hinode Science Schedule
  Coordinators.  An advanced plan is available under the planning web site:

  (Click on schedule - observer)

  All participants are requested to check the planning web-site given above
  and to complete missing ops details (if any). The web site is
  password-protected, contact the campaign POC for access.

  For information on SUMER preparatory and campaign ending activities see
  section 1c above.

  The number of HOPs/JOPs can not increase anymore, since the campaign time
  is almost fully booked. Given the interest in the community to
  participate in campaigns such as this one, SUMER may consider to expand
  the June activities (see below) or to consider a third campaign in
  November 2009.

  TRACE has not received any requests from JOP 214 & awaits date and
  program information.

  CDS requests to be added to the mailing list to receive information
  (including pointing coordinates) for all JOPs.

  MDI will support all requested observations as best we can, not changing
  HR pointing, observing sequence or observing mode on timescales less than
  24 h.

  Joint Observation Programs (JOPs) proposed for this campaign are
  listed below in JOP number order.

  178 Filament and its environment (footpoints and filament channel)

  195 Characterization of fast and slow solar wind source regions

  207 Eruptive and quiescent prominences Atlas with SOHO and Hinode

  210 Checking the possible drivers of solar wind origin in 
      the coronal hole

  214 Quiescent prominence structure and dynamics with Hinode

  215 Connection between the magnetic canopy and chromospheric/lower
      TR dynamics

  218 Dynamics and structure of the solar atmosphere from SUMER
      and VTT observations

  217 Velocity fields at the base of polar coronal holes

  219 Connection between photospheric vortex flows and transition
      region and coronal heating

  Comprehensive descriptions can be found on the Solar JOPs web page
  http://sohowww.nascom.nasa.gov/soc/JOPs/, compact descriptions (SOHO
  calendar entries) are shown below in order of their run dates.

  The campaign calendar has recently been updated to account for the SUMI
  launch suspension (minor shift and swap activities).

* Apr 16-28     JOP 214 Quiescent prominence structure and dynamics with 
                  (SUMER-Hinode campaign program ID 6),
                  POC: Tom Berger

  Currently scheduled to run on Apr 16-19, 21-27 (UT). For details see the
  campaign web site.

* Apr 16-28     JOP 215 Connection between the magnetic canopy and 
                  chromospheric/lower transition region dynamics,
                  (SUMER-Hinode campaign program ID 7),
                  POC: Anna Pietarila,

  Currently scheduled to run on Apr 16, 18-19, 21-28. For details see the
  campaign web site.

  HR observations specifically, hr_ve_fe_me, is requested from
  MDI. However, the JOP description indicates the MDI data is for
  coalignment, so would MDI synoptic HR images would be sufficient?  Will
  coordinate with JOP POC, but MDI may be in HR mode anyway for another
  SUMER/Hinode JOP.

  POC reply/comment on MDI: Any MDI HR data (also synoptic) support for JOP
  215 would be wonderful.

  POC reply/comment on SUMER and timing: Part of the SUMER observing
  sequences reserved for JOP215 will be most likely be used by Werner Curdt
  for Ly-alpha studies. Exact dates have not yet been decided.

* Apr 17, 20    JOP 218 Dynamics and structure of the solar atmosphere from 
                  SUMER and VTT observations
                  (SUMER-Hinode campaign program ID 20),
                  POC: L. Teriaca

  MDI will support with HR Magnetograms if the target is within the MDI
  high resolution (HR) field of view (HRFOV).

* Apr 17, 21    JOP 195 Characterization of fast and slow solar wind 
                  source regions
                  (SUMER-Hinode campaign program ID 23),
                  POC: Enrico Landi

* Apr 18-26     JOP 219 Connection between photospheric vortex flows and
                  transition region and coronal heating
                  (SUMER-Hinode campaign program ID 1),
                  POC: Davina Innes

  Currently scheduled to run on Apr 18, 22, 26. Requested DSN coverage for
  Apr 18 obtained, Apr 22 and 26 remain TBD. For details see the campaign
  web site.

  MDI will support with HR Magnetograms as requested if the target is
  within the MDI HRFOV.

* Apr 19, 24    JOP 210 Checking the possible drivers of solar wind origin 
                  in the coronal hole,
                  SUMER/Hinode-EIS/Hinode-SOT/Hinode-XRT (all TBC),
                  (SUMER-Hinode campaign program ID 3),
                  POC: Hui Tian. 

* Apr 20, 22    JOP 217 Velocity fields at the base of polar coronal holes
                  (SUMER-Hinode campaign program ID 19),
                  POC: L. Teriaca

* Apr 23-29     JOP 178 Filament and its environment
                  (footpoints and filament channel)
                  CDS/EIT/MDI/TRACE (all TBC)
                  (SUMER-Hinode campaign program ID 8),
                  POC: Brigitte Schmieder

  Currently scheduled to run on Apr 23-25 and 28-29. For details see the
  campaign web site.

  MDI has not gotten a formal request to support this, but as long as it
  does not conflict with JOP's 219/218/215 then MDI can support JOP178.  If
  MDI is running in HR mode, though, on any given day for another JOP and
  JOP178 wants us to switch to FD, we will not do so on timescales less
  than 24 hours.

  TRACE has also not gotten a request to support this JOP.

  EIT will support with 304 A CME watch binned 512x512 at the synoptic 12
  min cadence.  Final decision on this still TBC.  Comment: might SECCHI
  EUVI be more appropriate than EIT to support this JOPs goals?

* Apr 23-28     JOP 207/HOP 82 Eruptive and quiescent prominences Atlas with 
                  SOHO and Hinode
                  (SUMER-Hinode campaign program ID 16 & 17),
                  POC: Susanna Parenti

  The two different campaign program IDs refer to two different pointings.

  Currently scheduled to run on Apr 23-24 and 27-28. For details see the
  campaign web site.

* Apr 24 (TBC)  HERSCHEL sounding rocket launch, 
                  POC: Dan Moses, Lucia Abbo

  The rocket payload consists of a suite of 3 instruments:
  SCORE/Ultraviolet Coronagraph Imager (UVCI), Herschel EIT (HEIT) and
  Helium Coronagraph (HeCor).  The HERSCHEL Sun-Earth Sub-Orbital Program
  is a sounding-rocket payload designed to investigate Helium coronal
  abundance and solar wind acceleration from a range of solar source
  structures by obtaining simultaneous observations of the electron, proton
  and Helium Solar coronae. HERSCHEL will provide the first measurements of
  the coronal He abundance in source regions of the solar wind, thus
  bringing key elements to our understanding of the Sun-Earth connections.

  Timing and supporting SOHO instruments remain TBC. The HERSCHEL team is
  currently involved in integration and test activities. The critical
  milestones thereof are expected to be completed by the beginning of
  March. The official request on the launch date will not be made until

  EIT is OK with SOHO being in submode 5. Support will be a four-filter
  synoptic set binned over the rocket flight timing.

  LASCO support will be C2 pB set orange filter binned before and after the
  flight time around the EIT filter set.

  CDS will participate, taking on-disk He I and 2nd order He II
  observations.  Request to add CDS planner to the mailing list.

  See also section 2b (intercalibration activities) for proposed
  SOHO/STEREO/TRACE/HERSCHEL cross-calibration.

* May 15-Jul 12 TRACE not performing science operations

* May 17-Jul 21 MDI 60-day continuous contact

  Timing TBC. The continuous contact period will be a 60-day period within
  the dates listed above.

  MDI will run a Full Disk Dopplergram and Continuum image campaign for
  most of the 60 Day CC period.  This is different than the last several 60
  Day CC periods.  We will always run Velocity observations and will
  interrupt the Continuum observations during the 5 day Sunrise balloon
  flight.  We will not, however, run in High resolution mode, so only 1
  minute cadence, FD Magnetograms and Dopplergrams will be taken during the
  balloon flight.

* Jun 1-Jul 10  Sunrise 5-day balloon flight, MDI/SUMER/TRACE,
                  POC: Davina Innes

  In June or July 2009 a balloon borne solar observatory called 'Sunrise'
  is planned to be launched and SoHO (at least MDI and SUMER) as well as
  TRACE supports have been requested.

  The launch date will be sometime between Jun 1 and Jul 5, 2009 and the
  flight lasts 5 days. Coordinated observations with SoHO would therefore
  be for five days sometime between 1 June to 10 July 2009.  NOTE: TRACE
  has announced, that no science operations will be conducted from May 15 -
  July 12 (see also section 2c and

  A short description of SUNRISE is given in

  A tentative timeline of the flight is below:

  Major milestones (x = moment of tether cutting):

  x - 3 weeks: Hardware arrives at lauch facilty
  x - 3 days : Launch readiness review
  x - 3 days : SUMER opens aperture door (remotely)
  x -24 hours: Next day launch announcement
  x + 1 hour : Launch confirmed
  x + 6 hours: Ascent completed
  x + 6 hours: Switch-on sequence and initial tests
  x +12 hours: SUNRISE operational
  x +12 hours: SOHO submode switch
  x + 5 days : Science operations completed

  Submode change 6 -> 5 is proposed to take place during the next working
  shift after SUNRISE is launched. CDS concurs, as long as the submode
  change timing allows for CDS crash recovery (if needed) and loading on
  one single pass.

  MDI can support with full-disk, 1-min cadence magnetograms and
  dopplergrams if there is high rate at the time. MDI support will be the
  ONLY interruption to the 60 day CC plans of running a Full Disk Velocity
  and Continuum campaign.  See above notes for the 60 day CC period.

  SOHO will NOT go to record at any point for this flight since it will
  occur during the 60 day Continuous Contact period.

* Jul 22        Total Solar eclipse (around 0236 UT)

  Request for DSN coverage has been submitted and information on the
  coverage is expected in the end of March to early April timeframe.

* Jul 28 (TBC)  SUMI sounding rocket launch, CDS/MDI/TRACE, TBC
                  POC: Jonathan Cirtain (TBC)

  NOTE: launch postponed from Apr 16 to Jul 28. The new date is
  approcimately a week into the Aug 2009 keyhole, which very likely would
  restrict MDI and SUMER supports. The SUMI POCs have been notified and
  urged to move the launch to a better date, but no reply has been received

  MDI needs to know what observations (full-disk or high resolution) are
  needed for the SUMI rocket launch.

  TRACE has been asked to support this rocket launch. 

* Sep 30-Dec TBD TRACE not performing science operations

b) Intercalibration activities

  Last ICAL was: Mar 05

  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.

* Apr 6-10      ICAL01 (#7113), CDS/EIT/STEREO/Hinode-EIS(TBD)/Hinode-SOT(TBD)

* Apr 24 (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

* May 11-22     ICAL01 (#7113), CDS/EIT/STEREO/Hinode-EIS(TBD)/Hinode-SOT(TBD)

* Jun 15-19     ICAL01 (#7113), CDS/EIT/STEREO/Hinode-EIS(TBD)/Hinode-SOT(TBD)

  The Sunrise balloon flight period may need to be taken into account in

* Jul 13-17     ICAL01 (#7113), CDS/EIT/STEREO/Hinode-EIS(TBD)/Hinode-SOT(TBD)

* Aug 17-21     ICAL01 (#7113), CDS/EIT/STEREO/Hinode-EIS(TBD)/Hinode-SOT(TBD)

  NOTE: the Aug 2009 keyhole ends on 20 Aug 2009, hence this run should be
  possible during the proposed time, but may also be postponed to the
  following week.

* Sep 14-18     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.


  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.


  See section 2a for details.


  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.

  TRACE will not perform science operations from May 15 - July 12, and from
  September 30 through early December. See also

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.

  Apr 24
  May 29
  Jun 26
  Jul 24
  Aug 21
  Sep 25

  MDI:	  OK.

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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