SPWG FINAL MINUTES Friday June 27, 2003

1. Boundary conditions

* The SOHO High Gain Antenna (HGA) has a physical problem with
  executing commanded movements. As a result of this, SOHO will be
  experiencing "keyhole periods" with diminished amounts of science
  telemetry every 3 months (twice per orbit). The total duration of
  the keyhole periods will alternate (due to the asymmetry of the
  orbit) between about 18 days ("summer" and "winter" keyholes) and
  about 26 days ("fall" and "spring" keyholes). Below, numbers for
  the fall and spring keyholes are quoted in brackets behind the
  summer/winter numbers, e.g. 18 [26].

  During the first and last 4 [6] days of keyholes, we can still get
  high-rate telemetry on 34 meter DSN stations. During the central 10
  [16] days, we can get medium-rate telemetry (i.e. real-time data
  only, no recorder dumps) using the low-gain antenna on 34 meter
  stations, and high-rate telemetry on 70 meter stations.

  Thus the severity of the keyhole periods in terms of telemetry
  coverage depends heavily on the availability of 34-meter and
  70-meter DSN stations, given the current operations model. Other
  modes of operating SOHO to minimize the impact of the impaired HGA
  are being considered, but the current mode seems most likely:
  Keeping the HGA at the "sweet spot", rotating the spacecraft 180
  degrees every 3 months. SOHO is currently in it's first up-side down
  3-month period.

* The estimated dates for the next keyhole periods are:
* Sep 22        High Rate on 26m stations ends, TBC
* Sep 27        High Rate on 34m stations ends, TBC
* Oct 11        High Rate on 34m stations starts, TBC
* Oct 16        High Rate on 26m stations starts, TBC

* Dec 23        High Rate on 26m stations ends, TBC
* Dec 26        High Rate on 34m stations ends, TBC
* Jan 5, 2004   High Rate on 34m stations starts, TBC
* Jan 8, 2004   High Rate on 26m stations starts, TBC

* Mar 15, 2004  High Rate on 26m stations ends, TBC
* Mar 20,2004   High Rate on 34m stations ends, TBC
* Apr 2, 2004   High Rate on 34m stations starts, TBC
* Apr 7, 2004   High Rate on 26m stations starts, TBC

  As far as we can tell, the first keyhole period should get a fair
  amount of DSN coverage (maybe enough to get almost all medium-rate
  data). The situation looks worse for the following two keyhole
  periods, though.

* The next manoeuvre is tentatively being scheduled during the early
  stages of the next keyhole period.

  If SOHO continues to experience keyhole periods, all station
  keeping/momentum management manoeuvres will most likely be performed
  during the keyhole periods, to minimise the impacts on science
  observations. LASCO has asked to have the 180 degree rolls performed
  as early in the keyhole periods as possible, enabling them to
  develop a good background subtraction model for the new rotated
  position before we get solid contact again.

* Due to the HGA situation, these minutes are very late in coming out.
  The original idea was to incorporate changes due to the keyhole
  periods (present and future). However, with all that has been going
  on, half of what should be changed has already taken place, and
  we're soon about to send out the draft minutes for the next


* MDI continuous contacts: 

  Jul 23-28     MDI Continuous Contact
  Aug 27-Sep 1  MDI Continuous Contact
  Sep 10-Nov 23 MDI 60-Day Continuous Contact

  NOTE: Starting earlier than previously announced - end date
  unchanged for now, but it could be cut short after 60 days.

  LATEST: Since the next keyhole period comes right in the middle of
  the planned 60-day continuous period, it is now being reconsidered
  with DSN. There is a chance it may be moved to before the keyhole,
  or split 30 days before/after (with one solar rotation in between).

* Submodes: Submode 6 for the foreseeable future, except the following
  submode 5 periods:

  Aug 21-31    SUMER star observations, JOP169

* EIT Bakeout/CalRock/Shutterless/Other:

* Jun 24-Jul 14 EIT Bakeout (telemetry keyhole)
* Sep 13,17,21  EIT Shutterless #12 Segments 1, 2, Backup, TBC
* Sep 26-31     EIT Bakeout (tentative)
* Nov 26        EIT Shutterless #13, Segment 1, TBC
* Dec 3,10      EIT Shutterless #13, Segment 2, Backup, TBC

NOTE: All shutterless and bakeout dates are obviously TBD with keyhole

* Commanding outlook: See AOB section.

* Long-term DSN outlook: November 1, 2003 - March 1, 2004 is a very
  heavily subscribed time for DSN. We may see some less contact time
  than we are used to.

* No atmospheric absorption expected for TRACE at this time until late
  July or August.

2. Priorities for the coming month & more

a) Joint observing plans and campaigns

* Jun 19,30/
  Jul 3,12      Cross calibration with Mars Express, SWAN/SPICAM,
                  POC: Eric Quemerais

* Jun 27-Jul 14 Estimated SOHO Telemetry Keyhole

* Jun 23-25     JOP155 Polar Coronal Jets, POC: Danuta Dobrzycka & Kuen Ko
This was only run Jun 23-24 and only had partial instrument participation.

Possible reruns July 10-13 and October 17-23 (see UVCS individual
instrument plans).

UVCS: JOP 155 will be called during these two periods unless it falls
      within the 'black-out' time (and before UVCS is recovered and
      ready for observations). The July run does not seem likely.

* June 25/26    ICAL01, CDS/EIT, POC: CDS & EIT Planners

Looks like we'll be missing the ICAL this month.

* Jun 26-Jul 09 UVCS Coordinated Radio Observations During Cassini Conjunction

It is not run due to SOHO 'black-out'.

* Jul 15-18     JOP166 Oscillations in Coronal Bright Points, 
                  CDS/MDI/TRACE/EIT, POC: Gerry Doyle

EIT images are needed for near-real-time target selection.  TRACE has
agreed to this JOP and this timeframe. Will supply full disk mosaics
as needed in case of EIT bakeout being delayed to just before this

CDS will participate, using real-time pointing.

EIT will participate via CME watch.

MDI should be able to support JOP166 with FD Mags/Doppler
for two days and HR Mags for two days, as long as MDI is up and
running nominally by then.  Also, we will not switch modes (from FD to HR
and back) on time scales less than 24 hours (so 2 days consecutive of FD
then 2 days consecutive HR, for example, might work best).

We expect to reacquire the high gain antenna link around July 14/15.

* Jul 27-Aug 02	Coordinated observations, UVCS/CORONAS

* August        EIT Calibration Rocket (TBC), POC: Jeff Newmark

CalRock may be delayed until late November.

* Aug 25-31     JOP169 Evolving Active Region Loops, POC: Harry Warren,

* Sep 13,17,21  EIT Shutterless #12 Segments 1, 2, Backup, TBC

* Sep 7-27      JOP165 High Cadence Active Region Oscillations: Center to 
                  limb variation (TBC), CDS/MDI/EIT/TRACE/SPIRIT, 
                  POC: Dipankar Banerjee (

NOTE: Next keyhole period may start at 

CDS will support JOP165 and EIT shutterless. Need the date for EIT
calibration rocket.

MDI's ORIGINAL PLAN was to try to coordinate as long as it does not
conflict with the 60 day CC. The first month of the continuous would
be in full disk with magnetograms (i.e. only full disk observations
for JOP165).

MDI CHANGES: Plans for that time are TBD due to the next possible
keyhole period for SOHO.  We can make no firm commitments.

NOTE: An EIT bakeout may be in conflict w/JOP165 - see note under
EIT/LASCO individual observations.

TRACE is supporting JOP165 Sep 7-17.

* Sep 18-30     Moving Magnetic Features Around Sunspots, MDI/TRACE/Sac Peak,
                  POC: Mandy Hagenaar (, Ted Tarbell

MDI will support this (full disk magnetograms at 1 min cadence during
first month of continuous period).

MDI change: Plans for that timing are TBD due to the next possible
keyhole period for SOHO.  We can make no firm committments.

Continuing campaigns:

*               JOP159 CME's in Lyman-alpha (#6870), SWAN/LASCO/EIT/UVCS,
                  POC: Chris St Cyr, Eric Quemerais

Targets of opportunity for the whole period:

*               JOP136/MMOP009 Default RHESSI collaboration (#6850)
*               JOP153/MMOP003 Major Flare Watch (#6970)

Campaign number 6850 is for "individual instrument studies" selecting
an AR target [partially] influenced by the Max Millennium target.
This target will be observed by a significant number of ground based
observatories, so chances for serendipitous co-observations are good.

b) Intercalibration activities

Last Intercal 1: May 14

* Week 30/31    ICAL01, CDS/EIT, POC: CDS Planner

c) Individual instrument plans


See section 1 (boundary conditions) for MDI continuous contact periods.  

All requests for MDI support need to be made several months ahead of
time and sent to

MDI's REQUEST page is at
NOTE: Listing of a study on that page means *only* that a request has
been received, not that it will necessarily be supported.

  See their planning page (below) and the SOHO calendar for weekly plans.

  Coronal Jet Observations being planned for June 23-25 (JOP155
  listing in Joint Observations section above), July 10-13 and October
  17-23. Danuta Dobrzycka will contact instrument teams regarding the
  latter two periods later if support is requested.

JOP 155 will be called for the July and October runs unless it falls
      within the keyhole time (and before UVCS is recovered and
      ready for observations). The July run does not seem likely.

  See their request diary for details

GIS raw data dumps are being considered for June 23-29, requires NRT.

Raw dumps only happened on June 22 due to safing on June 24.


See section 1 (boundary conditions) for EIT bakeouts/shutterless and
other special items.

LASCO has been requested to support IPS measurements of slow solar wind 
between September 26-October 5. An EIT bakeout has been sheduled at the
September 26-31, giving LASCO higher cadence.

NOTE: There's a potential conflict with JOP165 (and possibly the Moving
Magnetic Features study).


Alfa-Leo and rho-Leo observations, JOP169, dates 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.

3. AOB

* Next SPWG: Friday July 25, right after weekly meeting in the EOF

There will be no trace rep here for the SPWG. Also we are likely to
support Harry Warrens proposed Loop JOP August 25 - 31

* DSN support should be requested 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.

* If anyone has projects that require high-cadence MDI support, now is a
  good time to ask! If you need MDI data, make sure you request it
  specifically. There is no significant change in the shutter performance
  over the last 10 months; monitoring continues, but no immediate changes
  in operations are planned.

* Commanding outlook

The DSN schedule before the end of the keyhole period is not
included. See daily/weekly meeting minutes etc for details.

Week 29 - Jul 14 - Jul 20: D27 for part of the day on Monday, Wednesday,
                           and Sunday. D27 all day on Tuesday and Thursday.
                           Large afternoon gaps on Wednesday and Friday.
                           Morning gap on Saturday and Sunday.

Week 30 - Jul 21 - Jul 27: Afternoon gap on Monday. D27 part of the day on 
                           Monday, Thursday, Saturday. D27 all day on
                           Tuesday and Wednesday. Downlink only station on
                           Friday afternoon. Sunday is good.

Week 31 - Jul 28 - Aug 03: Morning gap then D27 for Monday - Thursday.
                           Morning gap then good stations Friday - Sunday.