09 June 2023 - Mission Day: 10052 - DOY: 160
Science Operations


1. Boundary conditions

a) Orbit, attitude and manoeuvres

- SOHO is upside down (180 degrees).

- manoeuvres

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

  Feb 10 (TBC)  station-keeping & momentum management
  Feb 14 (TBC)  roll

  May 12 (TBC)  station-keeping, momentum management, roll

b) Communications with the spacecraft

  Graphical DSN schedule: http://soho.nascom.nasa.gov/soc/dsn/. NOTE: DSN
  coverage will be less during the Christmas and New Year holidays.

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

* Jan 25-Feb 21 26m Keyhole
* Feb 1-14      34m Keyhole

* Apr 28-May 16 26m Keyhole 
* May 02-12     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 (TBC). 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)
* Jan 16        EIT Shutterless #34 (SM6)
* Mar 27, Apr 2 EIT Shutterless #35 (SM6)
* Apr 15-29     SUMER campaign (TBC; 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.

  Shutterless run #34 has changed to only one day due to DSN.  Shutterless
  run #35 moved to allow SUMER to support the SUMI rocket flight during the
  SUMER spring observing campaign. For details see section 2a.

  SUMER will observe during the Sunrise balloon flight. Note, that the
  balloon launch is scheduled for Jun 1 - Jul 5.

  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.

e) Spacecraft maintenance activities

  Reduction of PLM heaters on the upper panels aimed at

  - cooling the FPSS (the temperature of which is above its qualification
    level), and
  - decreasing the power consumption

  has been accepted and the change was implemented on Dec 9, 2008. The
  original proposal is at
  and summary of the results and impacts at
  The new thermal steady state was reached approximately 24 h after the

f) Others

  TRACE eclipse season began on 13 Sep 2008.

  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

  FOT is currently developing and testing a software anomaly detection
  system, which would pause NRT only when needed instead of the current
  regular pauses. Due to problems in development the approach of regular
  pauses remains the operational approach until TBD time.

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.

* Jan 16        EIT shutterless #34, EIT/CDS/MDI/TRACE/STEREO,
                  POC: Susanna Parenti

  DSS-65 09:55-17:40, run-time 12:00-14:50 UT

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

* Jan 15-19     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

* Jan 23        HERSCHEL sounding rocket launch, EIT/LASCO/UVCS/STEREO/TRACE
                  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 are TBC. The HERSCHEL teams has
  requested 23 Jan 2009 at local solar noon as the launch time.  Any day
  that week from the 20th to the 23rd is free from science and programmatic
  objections.  HERSCHEL launch has to wait until January due to unexpected
  number of higher-priority missions from White Sands Missile Range.
  Current consensus is that HERSCHEL will get its first choice on the week
  of Jan 19.

  LASCO will support with (3) polarized image sets in 60, 0, and -60
  degrees at launch time.

  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.

* Mar 8         Daylight Savings Time begins in the USA,
                  change in GSFC at 07 UT

* Mar 25-30     MDI Continuous Contact (TBC)

  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 27        EIT shutterless #35 run 1, EIT/CDS/MDI/TRACE/STEREO,
                  POC: Susanna Parenti

  DSS-27 15:20-23:25 (MDI continuous)

  Run 2 is planned for Apr 2.

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

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

* Apr 2         EIT shutterless #35 run 2, EIT/CDS/MDI/TRACE/STEREO,
                  POC: Susanna Parenti

  DSS-27 18:55-0535
  DSS-46 23:35-0535

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

* Apr 15-29     SUMER Campaign, TBC

  The following JOPs have currently been proposed for the campaign. SUMER
  will also support the SUMI sounding rocket launch, tentatively set to Apr
  16, but timing remains TBC.

* Apr 15-29     JOP 210 Checking the possible drives of solar wind origin 
                  in the coronal hole,
                  SUMER/Hinode-EIS/Hinode-SOT/Hinode-XRT (all TBC),
                  POC: Hui Tian. 
                  Timing TBD.

* Apr 15-29      JOP 211 How does the solar wind originate from the 
                  quiet-Sun region,
                  SUMER/Hinode-EIS/Hinode-SOT/Hinode-XRT (all TBC),
                  POC: Hui Tian.
                  Timing TBD.

* Apr 15-29     JOP 212 Connection between UV explosive event and 
                  magnetic cancellation,
                  POC: Hui Tian.
                  Timing TBD.

* Apr 15-29     JOP 214 Quiescent prominence structure and dynamics with Hinode and 
                  La Palma, 
                  POC: Tom Berger

  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.

* Apr 16        SUMI sounding rocket launch, SUMER, TBC
                  POC: John Davis (TBC)

* 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 only do full disk, 1-min cadence Magnetograms and dopplergrams.

* 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.

  A short description of SUNRISE is given in

  MDI can support with full-disk, 1-min cadence magnetograms and
  dopplergrams if there is high rate at the time.

  Need for SOHO to be in record at any point for this balloon flight will
  be investigated.

* Jul 22        Total Solar eclipse (around 0236 UT)

  Request for DSN coverage has been submitted.

b) Intercalibration activities

  Last ICAL was: Dec 04

  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.

* Jan 5-9       ICAL01 (#7113), CDS/EIT/STEREO/Hinode-EIS(TBD)/Hinode-SOT(TBD)

* Jan 23        ICAL14 SOHO-STEREO-TRACE-HERSCHEL radiometric 
                  cross-calibration (TBC), EIT/LASCO/UVCS/STEREO/TRACE/HERSCHEL,
		  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
* Jan 26-30     ICAL01 (#7113), CDS/EIT/STEREO/Hinode-EIS(TBD)/Hinode-SOT(TBD)
  26-m keyhole begins on Jan 26 and 34-m keyhole begins on Feb 1. ICAL
  might still be possible during this period.

* Mar 2-6       ICAL01 (#7113), CDS/EIT/STEREO/Hinode-EIS(TBD)/Hinode-SOT(TBD)

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

* 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

  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-EIT 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 have a lot of "engineering" (calibrations, a tuning update and
  possibly a leg alignment) to complete before the 3-day continuous contact
  period starts 15 Jan 2009. This constraint is due to the HERSCHEL launch
  on 16 Jan 2009 (which could slip into the week of 19 Jan 2009),
  President's Day, Inauguration Day and the Feb 2009 keyhole (as of 25 Jan

  MDI will do Full Disk Velocity observations for March and September 2009.


  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.

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.

  Jan 23
  Feb 20
  Mar 27
  Apr 24
  May 29
  Jun 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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