OPERATIONS
Science Operations
FINAL MINUTES FOR SOHO 18 DECEMBER 2009 SPWG MEETING
FOR YOUR INFORMATION. As SOHO operations resources are being reduced and the mission is entering the lower-level phase (transition planned for 2010), the need and usefulness of the Science Planning Working Group (SPWG) meetings has diminished. It was hence decided to discontinue the SPWG meetings and this meeting was the last. The needs for SPWG type information dissemination will be met primarily via the SOHO calendar (http://sohowww.nascom.nasa.gov/soc/head_calendar.html) supplemented by other contacts and meetings on an as-needed basis. The usefulness of the SOHO calendar to users of the information can be enhanced by joining the SOHO-CALENDAR-UPDATES mailing list. This list is used to disseminate notifications of select calendar changes. To subscribe contact the SOCs by e-mail.
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 2 (TBC) station-keeping and momentum management
Feb 5 (TBC) roll (to approximately 0 degrees)
Apr 30 (TBC) station-keeping, momentum management and
roll (to approximately 180 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 to change the
Z-axis angle from -18.55 to -16.7 degrees (to reduce keyhole
durations). The keyhole durations will be 6-7 days shorter for the short
keyholes (summer and winter seasons) and 10-12 days for the long
keyholes.
Keyhole dates for the next 6 months:
* Jan 21-Feb 7 26m Keyhole
* Jan 26-Feb 3 34m Keyhole
* Apr 22-May 3 26m Keyhole
* Apr 24-May 1 34m Keyhole
All keyhole information is available at or via
http://soho.nascom.nasa.gov/soc/keyholes.html.
- 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)
* Jan 7, 14 EIT shutterless #38
* Apr 8, 15 EIT shutterless #39 (time TBC)
* Jul 8, 15 EIT shutterless #40 (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
e) Spacecraft maintenance activities
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
later.
f) Others
TRACE eclipse season began on Sep 13, 2008 and will be ongoing. Hard eclipses
started on Sep 13, 2009.
Daytime weekday passes are automated but attended. For proficiency
reasons FOT runs a crewed pass approximately once per week.
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
http://sohowww.nascom.nasa.gov/soc/nighttime_nrt.txt.
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: The testing of new patch subsets should not be done during
the 60 day overlap between MDI and SDO/HMI next year. That may mean that
the testing for the patch subset changes will have to occur before or
after May-July 2010.
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
* Jan 11-17 JOP 225 STEREO/SOHO joint plume campaign,
EIT/LASCO/STEREO-EUVI/STEREO-COR1/STEREO-COR2/STEREO-HI1
POC: Frédéric Auchère, Antoine Llebaria
The dates remain TBC. In addition to the standard sequances, EUVI will
take images approximately evry 30 min with a low compression ratio. EIT
will support with a 171 CME wtach. COR and LASCO contributions are being
discussed.
* Jan 7 (TBD) EIT shutterless #38 run 1
POC: David Berghmans
Runtime: 19:00-22:00 UT
* Jan 14 (TBD) EIT shutterless #38 run 2
POC: David Berghmans
Runtime: 19:00-22:00 UT
* Feb 3 (TBC) Solar Dynamics Observatory (SDO) launch
For launch date updates see
http://www.nasa.gov/missions/highlights/schedule.html. The commissioning
phase is planned to last 60 days and hence end in early April, 2010
(TBC).
* Feb 26-28 MDI continuous contact
* Mar TBD MDI continuous contact
Duration 3-5 days.
* Apr TBD MDI continuous contact
Duration 3-5 days.
* May 4-Jul 17 MDI 60-day continuous contact, MDI/SDO
Contingent on timely SDO launch and commissioning.
b) Intercalibration activities
Last ICAL was: November 19
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.
* 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)
* Mar 15-19 ICAL01 (#7113), CDS/EIT/STEREO/Hinode-EIS(TBD)/Hinode-SOT(TBD)
* Apr 12-16 ICAL01 (#7113), CDS/EIT/STEREO/Hinode-EIS(TBD)/Hinode-SOT(TBD)
* May 3-7 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
http://stereo-ssc.nascom.nasa.gov/plans.shtml).
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. Hinode teams will informed of
ICAL01 dates as soon as they have been fixed by EIT and CDS. Hinde
teams will then decide whether to participate.
c) Individual instrument plans
MDI:
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.html
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 reserves the March 2010 continuous contact (dates TBD) for FD
Helioseimology studies with Hinode-SOT.
UVCS:
For weekly plans, see the SOHO calendar and the UVCS planning page:
http://www.cfa.harvard.edu/uvcs/observations/obst.html.
CDS:
For details see http://solar.bnsc.rl.ac.uk/scientificops/request.shtml.
EIT/LASCO:
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:
The detector checkout on 8-9 Nov has shown that the central KBr coated
section of detector B has suffered a dramatic loss of gain, and that only
the "bare" side parts of the detector remain usable. The SUMER team
believes that the detector can be stabilized if operated at reduced high
voltage level. Under these conditions science operations are still
possible. Observing programs will have to be revised and adapted to the
new configuration.
SUMER does not plan any operations before SDO commissioning.
TRACE:
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
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 http://sohowww.nascom.nasa.gov/operations/SPWG/spwg-20080118.html * 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 http://sohowww.nascom.nasa.gov/operations/SPWG/spwg-20080118.html * 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 http://sohowww.nascom.nasa.gov/operations/SPWG/spwg-20080118.html * 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 http://sohowww.nascom.nasa.gov/operations/SPWG/spwg-20080118.html * SOHO calendar email notifications: no change, see URL http://sohowww.nascom.nasa.gov/operations/SPWG/spwg-20080118.html
