POLAR Telecon Agenda for May 5, 2006

 

Agenda:

 

0\. Upcoming Polar Telecon

1\. Operations

2\. Polar SWT Meeting

3\. Resident Archives White Paper

4\. MFE Data Processing Status

5\. CAMMICE Science Report (continued)

 

**0.  Upcoming Polar Telecon**

 

Friday, May 5, 2006

4 pm ET, 3 pm CT, 2 pm MT, 1 pm PT

PIs and their designated representatives will be telephoned at their
usual numbers.

Other participants may call in at:

800-857-6258, password POLAR TELECON

(Leader: John Sigwarth)

 

The web site for the final agenda will be:

<http://pwg.gsfc.nasa.gov/polar/telecons/2006May05/>

 

Future Polar Telecons

Next telecon: Friday July 14th, 2006

 

Future Telecon Science Discussion Schedule

\[Errors/omissions/preferences to: nicola.fox@jhuapl.edu\]

 

July 2006: VIS

August 2006: EFI

September 2006: TIMAS

October 2006: Hydra

November 2006: MFE

December 2006: CEPPAD

January 2007: TIDE

February 2007: PIXIE

March 2007: SEPS

April 2007: UVI

May 2007: MDI

June 2007: CAMMICE

 

**1. Operations**

 

If you have any concerns about Polar operations, please contact Nicky
Fox (<nicola.fox@jhuapl.edu>)

 

**GTM Upset**

At approximately 2011 UTC on DOY 108 (18 April), the Polar GTM (GGS
Telemetry Module) experienced an upset. The upset occurred during the
unattended period between supports (D27 EOT at 1545 UTC and D45 BOT at
2305 UTC). The CEPPAD, EFI, TIMAS, MFE, and HYDRA instruments were
affected. TIDE telemetry appeared nominal. On 109/0743 UTC, there was a
format change from contingency (Science mode 2) to science. At 1242 UTC,
the procedure was initiated with commands to recover the GTM. The
following commanding was part of that procedure:\
\
UTC             Instrument action\
12:42:14        MFE ADC turned OFF\
12:46:26        MFE ADC turned ON\
12:47:30        MAG electronics turned OFF\
12:49:35        MAG electronics turned ON\
12:50:54        HYDRA write protect enabled\
13:04:50        TIMAS HVM OFF\
\
The recovery of TIMAS continued with the next support and was completed
at \~1655 UTC. The MFE RTC was executed during the next support
beginning at 2120 UTC. CEPPAD and EFI appear to have recovered without
direct intervention.\
\
Polar GTM Upset History:\
\
GTM-1 Upset Events

-   May 6, 1998 (DOY 126, 08:15:27)

-   September 30, 1998 (DOY 273, 14:00:05)

-   October 22, 1998 (DOY 295, 21:48:50)

-   September 22, 2000 (DOY 266, 01:26:44)

 \
GTM Switch March 27, 2001 (DOY 086, 22:00)\
 \
GTM-2 Upset Events

-   November 10, 2003 (DOY 314, 18:26:38)

-   November 17, 2003 (DOY 321, 15:13:36)

-   November 24, 2003 (DOY 328, 16:38:08)

-   December 6, 2003 (DOY 340, 21:44:27)

-   December 18, 2003 (DOY 352, 09:37:02)

-   February 12, 2004 (DOY 043, 03:04:52)

-   March 3, 2004 (DOY 063, 20:14:33)

-   April 3, 2004 (DOY 094, 09:04:59)

-   July 29, 2004 (DOY 211, 20:51:19)

-   November 13, 2004 (DOY 318, 18:37:34)

-   January 21, 2005 (DOY 021, 04:00:58)

-   May 21, 2005 (DOY 141, 09:04:54)

-   June 3, 2005 (DOY 154, 07:57:08)

-   June 12, 2005 (DOY 165, 22:14:31)

-   July 31, 2005 (DOY 212, 17:40:46)

-   September 12, 2005 (DOY 255, 16:28:13)

-   April 18, 2006 (DOY 108, 20:11:13)

**Hemispherical Antenna Test**

 \
On 18 February 2006  (DOY 049), Polar\'s operating downlink Solid State
Power Amplifier, SSPA-2, suffered a loss of output power during a
real-time contact.  The power output from the SSPA-2 dropped permanently
from 17.08 W to 11.06 W as a result of the anomaly. This anomaly is very
similar to a failure (AR #487) that occurred on SSPA-1 on December 12,
2002 (02/346/16:05:00z).  Similar anomalies also occurred on the Wind
spacecraft in 1997 and 2000. As a result of the anomaly, the Polar
mission now experiences degraded data during some telemetry downlink
contacts. These are correlated with low aspect angles when the receiving
ground station is well away from the spin plane of the Polar
spacecraft.\
 \
The Polar Flight Operations Team (FOT) is evaluating the operational
benefit of using the hemispherical antennas in addition to the belt
antennas. These hemispherical antennas are designed for 0-60 and 120-180
degree aspect angles so their use would be limited to supports which lie
entirely within these ranges -- roughly 33-50% of supports.

The Polar +Z Hemispherical Antenna using Comm mode 11 was tested and the
results were very positive. The test was conducted Tuesday, April 25,
2006 during a support from 1730 - 2000 UTC. The test was delayed
slightly due to an unusual command system configuration on the ground.
After some minor reconfiguration at the ground-antenna site, the test
proceeded smoothly.\
\
Using the Polar spacecraft belt antennas in the nominal configuration,
Station D46 reported the Automatic Gain Control (AGC) at the beginning
of the support as -118. At this point, the aspect angle was \~20.7
degrees with degraded data and many missing minor frames.\
\
At 1802 UTC, the downlink was turned off. At \~1804 UTC, the downlink
was on with Comm mode 11 utilizing the +Z Hemispherical Antenna. SSPA #1
output power was 12.15 W and the station reported an AGC of -110 (.i.e.
an improvement of 8 dB---more than a factor of 6 improvement in signal
strength). At 1805:02 UT, the Ranging Channel was enabled. No degraded
data were seen while in this configuration. Command block testing
consisted of several no-op commands (/tick and /tock) and was
successful. The SCT load was uplinked and verified successfully. DTR1
playback was completed and verified with LZP.  The downlink was turned
off again at 1939:43 UTC in preparation of returning to Comm mode 10.\
\
Upon returning to Comm mode 10 (nominal belt antennas), the AGC was -122
(i.e. a drop of 12 dB---more than a factor of 15 in reduced signal
strength), the aspect angle was 28.5 degrees, and there were again lots
of degraded data.\
\
The ranging data was verified by the Flight Dynamics Facility (FDF) and
found to be of good quality. A meeting is being scheduled to discuss
operational impacts for the implementation of regular operations of the
hemispherical antenna during low aspect angle periods.

**Polar Attitude Determination Error**

Since the last maneuver it has been determined that the attitude
solutions for Polar, that is, the location of the spin axis relative to
the celestial sphere, contains large errors of \~ 1-2 degrees which are
well outside the specification of 0.2 degree. The error in the attitude
solution is due to the close alignment of the Sun, Earth, and Polar for
the available sun pulse and horizon pulse data during the February and
August time frames +/- \~ 1 month. Outside of these times, the attitude
determinations appear to be within specification. The accompanying plot
shows the planned solar aspect angles post maneuver (light blue) and the
actual values (magenta) obtained. The attitude error was verified using
images from the Polar/VIS. The FDF is investigating what can be done to
improve the spin axis attitude determination for these time periods and
what steps are necessary to correct the previous attitude
determinations.

\<img
src=\"http://pwg.gsfc.nasa.gov/polar/telecons/2006May05/sun_angle.gif\"
alt=\"Sun Angle Plot \" \>

![](media/image1.png){width="5.995138888888889in"
height="4.627083333333333in"}

**Sun Angle Maneuver**

 

The next Polar maneuver is tentatively scheduled for October 21, 2006

**2. Polar SWT Meeting**

The next Polar Science Working Team meeting will take place on June 7-8,
2006, at The Doubletree Hotel & Executive Meeting Center, Berkeley
Marina, Berkeley, CA USA. The meeting web site can be found at

<http://pwg.gsfc.nasa.gov/polar/> Registration for the meeting is open
now. A group rate has been negotiated with the hotel. This will be
available as soon as all of the contracts are signed. A reminder message
will be sent out when the hotel reservations are available. We
anticipate a full day of science presentations and an operations
discussion on the first day, with a continuation of science
presentations on the second. It is anticipated that the meeting will
finish at 3pm on the second day allowing people plenty of time to catch
evening flights. There will be a registration fee of \$140 which will
include breakfast, lunch and snacks for both days. We will be going out
to a local restaurant for a group dinner on the Wednesday evening
(7^th^).

**3. Resident Archives**

The Polar mission is directed to write a white paper proposing the
structure of resident archives for the Polar data.  We are encouraged to
take as many cost saving measures as possible (i.e.) combining data sets
within institutions or across institutions where it makes financial
sense.  This white paper on the Polar resident archives is due June 1,
2006. 

Previously we had agreed on the following principles for the resident
archives:

> 1\. The resident archives are to be distributed at the PI institutions
> or their designated locations where the expertise in handling the
> specific data resides. (GSFC is not to be the sole repository for all
> of the data).
>
> 2\. Maximal support might be of order 1/4 FTE (i.e., \~\$50 K plus
> hardware maintenance)
>
> 3\. The archives should provide the highest possible resolution
> (spatial and temporal).
>
> 4\. The data should be available without human intervention.
>
> 5\. The archive should provide dynamic access to virtual
> observatories.
>
> 6\. Every site should provide direct links with brief descriptions of
> every other Polar site.
>
> 7\. Every archive should allow ASCII downloads of low and high
> resolution data for replotting by the requestor.
>
> 8\. Every site should allow plots of the data, either previously made
> or made on demand
>
> 9\. Positional and attitude information for the Polar spacecraft
> should be provided at one or more sites.
>
> 10\. Documented procedures for producing scientifically useful data
> from the Polar instruments will be made available and will be a
> fundamental element of the resident archives.

For information purposes, the instructions for this white paper are
given below.

 

Feb 7, 2006

 

SUBJECT:      Instructions for Resident Archive White Paper

* *

The Heliophysics Division is transforming our ways of archiving data by
adopting the concept of resident archives.  Typically while a mission is
active, its data are served to the research community through a loose
network of data servers (active archives) that are located at mission
data centers and instrument sites as well as at multimission servers
such as the Solar Data Analysis Center and the Space Physics Data
Facility.  We are finding that because of advances in information
technology, it is desirable and cost effective to continue serving
mission data under the supervision of the mission's data providers; i.e.
"resident" with the scientists that produced the data.  The architecture
for networks of resident archives is diffuse and all resident data sets
will not stand alone.  The concept allows for grass roots consolidation
of data servers along institutional lines, along lines of comparable
instruments, as well as along mission lines or in the multimission data
facilities.  Resident archives need to seek their own low-cost solutions
for continuation of service.

 

The period of "residence" will not be "forever".  The resident archives
will be subject to periodic peer reviews to determine if the archive is
still of value to the research community, if it should it be merged with
other resident archives, or if it should be terminated with the data
sets going to NASA's permanent data archives.  We are formulating the
processes for initiating, maintaining, and reviewing resident archives.

 

Recent experiences have shown that when a veteran mission retires, its
data are not quite ready for their resident archive(s).  There is work
to be done by the science team before it disbands.  Most instrument
teams have lists of unfinished tasks, improvements and updating
documentation that are important but have not been done due to higher
priority activities while the mission is still operating. 

 

Prepare and submit a white paper by June 1, 2006, discussing your
concepts and configuration for establishing one or more resident
archives upon termination of your mission.  In addition, consider the
hypothetical situation that your mission failed tomorrow and describe
those unfinished tasks that need to be done to serve your data to the
community from the resident archive.  List the tasks in priority order
with the idea that the most important tasks will be accomplished within
one year following the cessation of operations.  The less important may
be accomplished under the sponsorship of one of our competitive research
programs.

 

**4. MFE Data Processing Status**

 

**5.  The CAMMICE Science Report**

[The CAMMICE Science Report
(Powerpoint)](http://pwg.gsfc.nasa.gov/polar/telecons/2006May05/CAMMICE_PI_May06presentation.ppt)

[The CAMMICE Science Report
(PDF)](http://pwg.gsfc.nasa.gov/polar/telecons/2006May05/CAMMICE_PI_May06presentation.pdf)