SOHO SPWG Minutes
DECEMBER SPWG MEETING MINUTES
December 18, 1997
Chair: Laura Allen (NASA/SOC)
Notes: Emily Zamkoff (MDI)/Julia Saba (MDI)/Laura Allen (SOC)
Attendees: Vicente Domingo (ESA), Joe Gurman (EIT), Julia Saba (MDI),
Emily Zamkoff (MDI), Chris St. Cyr (LASCO), Andrzej Fludra (CDS),
John Kohl (UVCS), Don Michels (LASCO), Philippe Lemaire (SUMER),
Ester Antonucci (UVCS), Harold Benefield (FOT)
1. Review of Action Items
- SOC to solicit requests for collaboration from SOHO during February 26
Piet Martens has received several proposals which are attached at the end
of the minutes (see below). From the list of e-mails appended below,
Dr. Kariappa's is vague.
* New Action: P. Martens to contact Dr. Kariyappa to learn what observations
he desires from which SOHO instruments and what observations he will provide.
Phil Judge made HAO request at the SWT (written up as JOP071, see JOP-list).
John Kohl mentioned that Shadia Habbal has observations planned with Galileo
radio scintillation measurements.
Contacts for coordination of SOHO eclipse observations:
Shadia Habbal for UVCS, Russ Howard for LASCO, Klaus Wilhelm for SUMER.
Request has been made for DSN contact with uninterrupted telemetry
and NRT commanding capability from 16-20 UT. No problems are seen with this
There should be a SOHO internal integrated plan for eclipse observing
as well as an external plan posted on the web.
* Action: P. Martens will write up a summary eclipse plan based on input
from SOHO teams and outside coordinating observers.
- SOC requests EIT specification for proposed S/C offset for flat fielding
after 3 months continuous contact.
SOC received e-mail from people that wanted to know why the offpoint was
necessary: Why were the CDS full sun scans in 304 not sufficient..?
Joe Gurman supplied the following URL: http://eitv2.nascom.nasa.gov/cds.html
which shows some attempts to flat-field EIT with CDS data.
Basically, a lot of solar features are still present.
EIT requests one hour dwell at each of two off-pointed positions: 25 arcmin
off East limb and 25 arcmin off West limb. FOT received a message from
Ton van Overbeek that may speed up the duration of this operation.
The total offpointing can be done in approximately 3 hrs. This includes
1 hour dwells at +/- 25 arcmin. At least an hour should be added to either
end for FOT SVM activities. The offpointing would be done in Normal Mode.
(Note: EIT would really like 40 arcminutes offpoint; however,
they were told of restrictions with FPSS that regardless of mode (NM, RMW)
the limit of travel is 30 arcminutes).
Request has not yet been approved by SWT officially. Plan is to submit the
proposal with FOT timing inputs to Vicente Domingo. Vicente will e-mail
the proposal to the SWT and ask for a response to this request before
the January SPWG.
- Instruments need to give inputs to the SOC for the next roll maneuver.
Deadline is January 22 (day before next SPWG). SOC requests an e-mail
with detailed requirements. SOC will then work out conflicts
and provide input to FOT by January 30.
The MDI team requests 12 equally spaced positions (30 degree steps),
with 20 min dwell at each position; then SWAN would want to go to the
+90 degree position for the remainder of the dwell time. (Keeping in
mind the 16 hour constraint which is the total duration of the maneuver
defined by normal pointing mode transitions).
SUMER also wants to do a polar scan.
SOC needs an e-mail specifing:
- SUMER wants a polar scan at +90, how long does this scan take..?
(give minimum required time, plus maximum desired time..)?
- MDI, what is the minimum and desired dwell times at each 30
degree position.... will these values change from last time based
on experience from last roll...?
- SVM Activities for the Week of April 13: (Note this is Easter week.)
Apr 13 - Gyro Cal and possible Mom Mgt
Apr 14 - E-W Offpointing (3 hours), if approved by SWT
Apr 15 - Oblateness Roll (16 hours constaint NM --> NM)
Apr 16 - SK/Mom Mgt, RW4 Maint
Apr 17 - SSU Software Patch
2. Boundary Conditions for the Coming Month
- Friday January 9: Beginning of 3-Month Continuous Contact. Best effort
month is the last month of those 90 days.
Some discussion on the bad telemetry from DSS-27. Joe Gurman expressed
concern and frustration with bad data and lots of equipment anomalies.
Laura Allen pointed out that last week there were roughly 150 minutes of
unrecoverable data from DSS-27 alone and has received e-mail from CDS PI
also expressing concern.
* Action: DSS27 problems may adversely affect the upcoming continuous contact
so A. Poland/J. Gurman will talk to Dr. Rothenberg about better DSN
support during the prime SOHO mission.
The last month of MDI continuous contact will have ranging to prepare
for the April maneuvers so the FOT will put the SSR into record for the
ranging handovers. Probably the best time to dump the recorded data is right
after the gap, and MDI said it is probably okay to dump the data right away
unless there are other constraints. FOT will dump only the telemetry missed
to minimize loss of MDI high rate data (they will keep carefully track of addresses).
* Action on FOT to provide information to MDI team on number/pattern of
ranging handovers as soon as information available so impact can be estimated
and plan worked out not to bias MDI data systematically.
January 1-2: Submode 2, January 2-31: Submode 6
SUMER will be on for 3 weeks in February and requests 4 days of high rate
telemetry - Feb 8/9 and 15/16. LASCO/EIT will accept submode 4 for those days.
CDS will also.
During February eclipse SUMER wants to observe; LASCO/EIT had initially
requested Submode 6 during the eclipse, but they CDS, and SUMER need to
work out observing plans. This will be revisited at the next SPWG.
LASCO will also contact Klaus Wilhelm regarding SUMER eclipse observations.
CDS requested high-rate telemetry in March (first couple of weeks is best
because TRACE won't be needing EIT collaboration until mid-March at earliest).
This will be revisited at next SPWG.
Other discussion: There seems to have been some miscommunication between
CDS and LASCO/EIT teams. LASCO/EIT only asked for submode #2 (vice 6) because
they thought the CDS operators/planners were going to reduced staffing for
the holidays and did not want the telemetry. LASCO/EIT will only ask for
Submode #2 in these types of situations or if there are spacecraft burns
when CDS is closing door and may not need it.
CDS gave up the telemetry and expected to have an equal time of Submode
#3 in return. LASCO/EIT is not completely happy with Submode #3.
There was some discussion about a LASCO/EIT request to look at a
revised Submode #3. Currently, the present submode #3 gives LASCO/EIT
32 packets (36 was not deemed workable by the ESA/MATRA engineers) which
is 4 packets less than they currently get in submode #5. LASCO/EIT
just wants permission from the CDS PI to ask the ESA/MATRA engineers
to investigate the possiblity of other packet combinations which
would still give CDS high rate -- but would not impact them significantly.
It would be nice if the engineers could look into this before the March
period in which CDS would like high rate data.
* Action: V. Domingo will talk to R. Harrison (CDS PI) about the request
that ESA/MATRA investigate other possibilities of developing a telemetry
submode (or adjusting submode 3) to give nominal telemetry rate to LASCO/EIT
and enhanced telemetry to CDS when SUMER is off.
3. Preview of future months
- Plans for scheduled PACOR Bldg 23 power outages.
Two power outages on the weekends of Mar 20 and April 24 in building 23,
for replacement of the electrical loadcenters. The outages will begin Friday
afternoon, when the computers and facilities will be shut down, and last
until Monday afternoon, when the facility is stabilized and computers are
re-activated. EOF will not get telemetry so most commanding if needed
should be delayed loads. NRT commanding can be done but the FOT will require
an instrument representative in the MOR to watch the housekeeping data during the
commanding. Instrument health & safety can also be monitored using
POCC terminal in ECS office.
- TRACE launch date is now Feb 25 although it might slip into March. If TRACE
launches on Feb 25 then the 30 day science plan will start around April 1.
- Feb 1 is TR Maintenance/Memory Dumps. FOT will try to perform these memory
dumps on weekends from now on, since less instrument commanding on weekends.
- See Monthly Calendar at:
4. Priorities for Coming Month
a) Instrument Plans:
CDS: Doing mostly JOPS and active region studies. Jan 26-28 will do
Real-Time Operations program. Eddy Breeveld will be EOF planner
images will be made and shipped to England where a planner
there will make real-time decision where to point.
Full-Sun, full-spectrum observations
(every 2/3 months) to get total solar spectral irradiance (integrated
over 4 arcmin in N-S direction; 24 arcsec steps E-W). Joint CDS/EIT
full Sun scan put off another month - EIT will run this every other
August - 2nd Whole Sun Month. Andrzej Fludra is developing comprehensive
August 4-18 1999 - UK Total Eclipse (August 11) support activity!
UVCS: See UVCS home page for dates of following studies:
Global dynamics of extended corona; Lyman-alpha above 3 solar radii;
visible light power spectrum in polar plume/interplume regions
(SOHO GI program of L. Offman); with CDS, MHD waves in streamers and
LASCO: Denis Socker is planner then George Simnett. C2/C3
calibrations to be done in week 3.
EIT: JOP063 when prominence avaiable. Frequent two-filter (171/195)
CME watch in January.
MDI: Calibrations and software load in Week 2 and then high-cadence
helioseismology during continuous contact; might run different program
in third month, such as full-disk dopplergram + high-resolution
magnetogram. During first two months of continuous contact, no
magnetograms except for 96-minute synoptic full-disk magnetograms.
b) Flight of XUV Doppler telescope on ISAS sounding rocket set for Jan 31,
04:00 - 06:00 UT. No instrument representative at the meeting has heard
any concrete plans of what is desired from them. Joe Gurman volunteered to
organize this and contact Saku Tsuneta for plans.
Launch will occur during continuous contact. SOC has requested NRT
capability with no handovers during the launch window specified.
JOP063 planned for Week 2
JOP074 hasn't been approved yet. OK'ed by EIT. Nat Gopalswamy should
contact other instrument teams whose support is needed.
5. New JOPs
- JOP074, "A Study of Filaments and their Environments using VLA, SOHO &
Yohkoh", Nat Gopalswamy
* Next SPWG agreed for Friday January 23 (4th Friday).
* SUMMARY OF ECLIPSE OBSERVATION REQUESTS RECEIVED:
>From email@example.com Thu Dec 11 02:25 EST 1997
Date: Thu, 11 Dec 1997 12:57:27 +0500
From: firstname.lastname@example.org (r.kariyappa)
Dear Dr. Piet Matens,
Thanks for the information on Observations of the Corona during February 26,
1998 Solar Eclipse. I would like to have collaborative observations with
SOHO on this occasion. I present below a brief note on the observing program
and scientific goal:
Coronal Oscillations and Heating
1. High temporal (less than 1 sec ) resolution observations in coronal
lines (2-3 lines simultaneously) during eclipse.
2. The above observations leads to answer to the probelems: (i) Coronal
Oscillations; (ii) Coronal Heating Mechanism. It is known from earlier work
of many people that the period of oscillations decreases from photosphere
(5-min) to middle chromosphere (3-min). It is very interesting to know the
coronal oscillation in this contest.
I would be interested in joint observations. I would appreciate if you
can include my observing request with your Observational Program. I look
forward to hear more from you. Thanks !
With Kind Regards, Kariyappa
Dr. R. Kariyappa Phone: 91-80-553-0672
Indian Institute of Astrophysics Fax: 91-80-553-4043
Koramangala, Bangalore 560034 Email: email@example.com
Here is a description of our possible eclipse observations (still under discussion).
Can you help from Pointe-a Pitre as well as for SOHO coordination?
SCIENCE GOALS of 26 Feb 1998 Total Eclipse Observations from SO division
1) Determination of equivalent coronal densities and temperature in coronal
plumes and streamers (follow up nov. 94 results, experiments A, C)
2) High resolution coronal observations in stereo with SOHO (experiment A)
3) Measure of extended cool material distribution in the corona in H alpha
At Pointe a Pitre (scientists B.H. Foing, K. Muglach, P. Martens,
also attending the colloquium on Coronal plumes and jets (23-26 Feb)
and T. Beaufort technical support)
- other collaborators carrying photographic experiments
- coordination of analysis with SOHO EIT/LASCO observations
A) Automatic Meade 25 cm Photometrics PXL CCD camera and filters/objective
grating ( as for nov94 eclipse)
(T. Beaufort, B.H. Foing)
B) Automatic Meade Photometrics series with 300 CCD 2kx2k camera + H alpha
(K. Muglach, B.H. Foing)
C) Additional support imaging with Celestron 5 telescope and Vixen GPDX
(P. Martens and local collaborators from solar conference)
9 -14 January Tests OHP TB, BHF
18 Jan-5 Febr. Tests ESTEC BHF, TB, KM
7 February Transport Equipment to Guadeloupe via Paris
Sat 21 Febr Departure for Guadeloupe (BHF, KM, TB)
22-26 Febr. Installation, preparation, and tests of observations
23-26 Febr. in parallel to colloquium on Coronal plumes and jets
26 Febr. Total solar eclipse observations and calibrations
27 Febr. Preliminary evaluation and equipement packaging
28 Febr. End of mission
>From SOHO, we 'd like to compare coronal temperatures and densities maps
and values for the one we shall derive from our white light images.
Also white light LASCO coould be compared to ours for stereo info on the
inner corona. Finally some programmes on prominences can be done in
He and Lyman lines, in complement to their optical counterpart.
>From firstname.lastname@example.org Thu Dec 11 17:49 EST 1997
Date: Thu, 11 Dec 1997 17:49:08 -0500
To: "Petrus C. Martens"
To: Petrus Martens
cc: Guenter Brueckner
Hello. I am replying to the SolarNews announcement of requests for
I am planning a set of eclipse observations from Aruba. They include
a search for 1-Hz oscillations in the coronal green line; a coronal
temperature map through the Cram method of comparison of ultraviolet
bands sensitive to the Doppler broadening of the photospheric
absorption spectra at coronal temperatures; and a set of CCD images
through a green continuum filter closely matching one of the bands on
the LASCO C1 coronagraph and with a similar field of view. The last
observation, in collaboration with Guenter Brueckner, should provide a
scattered-light calibration for that coronagraph.
I hope, therefore, that there will be LASCO C1 observations at the
time of the Aruba eclipse and a set of EIT observations as close as
possible in time. The second experiment above should give
temperatures that could be compared with EIT temperatures. The
eclipse in Aruba will occur at 18:10:30 UT plus and minus 1 min 45 s
(for a total of 3 m 30 s of totality)..
I have set up an eclipse homepage, in my role as Chair of the IAU
Working Group on Eclipses, and would be glad to include whatever
hotlinks to eclipse research that you might recommend. The SOHO
homepage is already linked.
With best wishes,
>From Frederic.Clette@ksb-orb.oma.be Thu Dec 18 05:24 EST 1997
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From: Frederic Clette
Subject: Eclipse 98 projects
Date: Thu, 18 Dec 1997 10:07:27 +0000 (UTC)
Cc: firstname.lastname@example.org (Jean-Rene Gabryl),
email@example.com (David Berghmans)
X-Mailer: ELM [$Revision: 184.108.40.206 $]
Hello, Piet !
Following your call for proposals of joint observations, I submit here a
brief description of our ground based experiments, which can involve a
collaboration with SOHO instruments, mainly LASCO and EIT.
- Main observing site : NW of Curacao Island (Kadushi Cliffs), altitude = 0m.
- Team : about 20, 4 professionals working together with a group of amateur
astronomers (experienced eclipse chasers).
- white-light polarization (photographic) :
- 70/1000mm refractor, 6-position linear polarizer, 24X36 Tmax emulsion,
two sites (Curacao, Colombian mountains)
- purpose : absolute determination of the electron density distribution
from 1 to 3 Rsun (ongoing program since 1973, using the same basic
instrument for continuity).
- white-light polarization (CCD) :
- 760x580 pixel array, video output with pixel-clock synchronization,
8-bit digitization (3 exposure ranges), rotating linear polarizer with
continuous image readout (0.5 to 2 Hz) givin a minimum of 12 images
over a 1800 rotation, 200mm/f-2.8 telelens.
- purpose : same as photographic experiment, but with a higher accuracy
(in particular for the polarization angle). This is an upgrade
version of this experiment which was already carried out successfully
in 91 and 94.
Proposal of collaboration :
The joint study of simultaneous polarimetric observations from the ground and
from LASCO C1 and C2 would allow a cross-calibration of both data sets in the
range 1.1 to 3 Rsun. C2 images would improve the quality of ground-based data
in the outer part of the observable corona (2 - 3 Rsun and extending G-B data
beyond 3 Rsun). On the other hand, the good quality of ground-based white-light
observations relative to the C1 white-light channel would help in improving
the connection between the C1 and C2 fields of view, by filling-in the gap
2.5 - 3 Rsun where C1 hardly detects the corona.
Moreover, simultaneous synoptic images by EIT (fffr) as well as the regular
synoptic maps produced by B. Thompson can be used to remove the ambiguity
in the third dimension (depth along the line of sight) when reconstructing
the global electron density distribution. This would refine the ongoing study
that we conducted already for several eclipses, by taking advantage of this
unique information that was not available before SOHO. A cross-calibration of
the electron densities derived from electron scattering and EUV emission lines
in the lower corona can also be considered, as one of us (J.-R. Gabryl) has
been developing a method to fit the on-disk and off-limb EUV intensity
gradients to radial models of the electron distribution.
Of course, this EIT part of our project is part of our participation to the
EIT science program as co-investigators. We would thus ask first to get
involved in the LASCO Eclipse98 plan and then, to be informed of any proposal
related to joint analysis of GB and EIT data (will this be handled through the
normal proposal reviewing process associated with each instrument ?).
Observatoire Royal de Belgique
Departement de Radioastronomie et de Physique Solaire
Avenue Circulaire, 3
tel : ../32/(0)2/373.02.33
fax : ../32/(0)2/373.02.24
e-mail : firstname.lastname@example.org
meeting ajourned ~ 1:00 pm.