********************************************************************
UARS WEEKLY STATUS REPORT - 21 JAN 2005
********************************************************************
***********
SOLSTICE
***********
SOLSTICE resumed normal operations this week (doy 015) after performing
day only operations in support of the yaw maneuver. Otherwise, the
instrument continues to perform well, taking solar data on all
available orbital tracking periods. An average of 56% of data were
returned this week accounting for 388 minutes of solar observing time
per day.
***********
SUSIM
***********
SUSIM successfully gathered daily mid (1.1 nm) resolution, MgII,
occultation, solar pointing offset, and continuous monitoring scans
for time periods with UARS telemetry or tape recording.
***********
PEM
***********
The new PEM2K:: is now fully configured and functional. All communication
paths should function as normal.
HEPSA data files are version 2. Currently, HEPSA data between 1991274
and 2004259 has been reprocessed and archived at the GSFC DAAC. HEPSA data
between 2004260 and 2004269 are currently being processed.
MEPS data files are version 1. Processed MEPS data files at the DAAC
archive are between 1991274 and 2004239. MEPS data between 2004240 and 2004259
are waiting for archival at the DAAC.
PEM continues to receive NMC data files from NOAA. No problems have
been encountered.
The PEM data from the GUVI conjunction periods may be found at
http://wwwpem.space.swri.edu/guvi-pem.html. The additional electron data for
the October and November storms of 2003 has been moved and is now located at
http://climatology.space.swri.edu/uars_fromRudy.html. For those users of
SDDAS, update your UARS Meta data and these data times will appear
with full functionality. Proton data from these storms are now located at
http://climatology.space.swri.edu/UARS_images_from_Rudy_(Apr._2004).html
Requests have been received for storm spectral data. Overview plots were
produced and these plots may be found on the web at
http://climatology.space.swri.edu/UARS_images_postedJune2004.html
for the storms of October 29 of 1991, November 8-9 of 1991, April 6-7 of 2000,
March 31 - April 1 of 2001, April 11-12 of 2001, November 6-7 of 2001, and
November 11-12 of 2001.
*Beginning of power orbit day (PEM activation): array current >5 amps, array
voltage >53.5 volts, and battery current >2.0 amps.
End of power orbit day (PEM deactivation): time in power orbit day >4 minutes,
array current <9 amps, and battery currents <0.2 amps.
Power orbit day variation: ~39-40 min at yaw to ~50-51 min at maximum beta.
***********
HALOE
***********
Nothing received.
***********
MLS
***********
Nothing received.
***********
HRDI
***********
Nothing received.
***********
MPG
***********
The MPG continues to serve as the point-of-contact for UARS
instrument operations in support of the Science Traceability
Mission of UARS.
Daily processing of instrument Daily Activity Plans continues
with no problems.
***********
CDHF
***********
Nothing received.
***********
FOT
***********
REPORTING PERIOD
This report covers 08 January 2005 (Orbit 72940, GMT Day 008) through
15 January 2005 (Orbit 73045, GMT Day 014).
SPACECRAFT OPERATION
The observatory is now in Forward Flight (Southern Hemisphere viewing)
and is performing nominally under two-battery operations. The
instrument operational changes were:
INSTRUMENT OPERATIONAL CHANGES
Instrument Time Orbit Comment
HALOE 009/2239 72969 POWER OFF
SUSIM 010/2206 72984 POWER OFF
SOLSTICE 010/2312 72984 FULLTIME TO DAY-ONLY OPS
HRDI 011/0237 72986 DAY ONLY TO LOW POWER
WINDII 011/2203 72999 B/U A OFF
A Reverse-to-Forward Yaw Around maneuver (number 136) was successfully
executed in Orbit 73009 beginning 012/ 15:12:27Z and completing at
012/ 15:49:37Z on 12 January 2005. All instruments were in their off
or standby mode (except for SOLSTICE in day-only). Due to the SA
position at 269 degrees, the effective night length of the spacecraft
after the maneuver was approximately 55.71 minutes. Post maneuver
analysis of data indicate that during the Yaw Around, the end-of-night
load bus voltage was 26.08 volts and the average depths of discharge
(DODs) on Batteries 2 and 3 were approximately 20.04 and 18.87 percent
respectively. The next (forward-to-reverse) YAW is scheduled for 12
February 2005 (DOY 043).
The beta angle ranged between the angles of 0.0 degrees to 08.3
degrees for this report period. The beta angle is now increasing
towards a maximum angle of 39 degrees on 27 January 2005 (DOY 027).
Spacecraft battery 1, 2, and 3 performance monitoring continues.
Battery 1 remains OFF the charge relay. Battery 2 and Battery 3 are
currently maintaining greater than 23.6 V end-of-night (EON) load bus
voltage. Battery temperatures are stable with a temperature delta
between Battery 2 and Battery 3 of 1.59 to 1.60 degrees C. Additional
battery performance data for each battery on 07 January 2005 and 14
January 2005 are provided in Appendix D.
The clock error ranged from 10.6 to -10.0 msec during this report
period. Clock rate adjustments are listed in Appendix C.
All instrument and subsystem engineers were advised on the initial
excursion of ALERTS or Out-Of-Limits conditions detected by the FOT
for this report. A summary is listed below and the details of ALERT
and Out-Of-Limits occurrences are listed in Appendix B.
OUT-OF-LIMITS = 00
ALERTS = 02
The following real-time command sheets were executed for the listed
operational element(s) during this report period (see Appendix A).
FOT = 07
HALOE = 01
SUSIM = 01
SOLSTICE = 01
HRDI = 01
WINDII = 01
UARS Anomaly Reports initiated during this report period are listed in
Appendix E and summarized below.
FOT = 02
Two (2) Anomaly Reports remained OPEN at the end of this report period
(see Appendix E).
GROUND SYSTEM OPERATION
One (1) operational support problem occurred this period. Anomaly
Reports are included in Appendix E.
The data loss calculations are no longer being supplied by Data
Capture Facility (DCF).
OTHER SIGNIFICANT EVENTS
UARS SATELLITE OPERATIONS
This week the FOT started noticing the differential voltage on battery
3 drop on 11 January 2005. Around 1600 GMT the differential voltage
broke -200 mV. The online crew was told to continue to monitor the
value closely. For the remainder of the day, it seemed to come back
down periodically, so there wasn't much concern.
Then around 0800 GMT on 12 January 2005 the differential voltage hit
-274 mV. All instruments were in there off or standby state for the
upcoming yaw maneuver, so load shedding was not an option. The FOT
continued to track the anomaly and was told to report if the
differential voltage hit -300 mV. This happened around 012/1330 GMT,
which was the orbit before the yaw maneuver. The NASA power branch
engineer was notified and the FOT went forward with the maneuver. As
a precautionary measure, the FOT disabled the MLS heater operations
(012/1431 GMT), so that the batteries could recover better following
the yaw. After the yaw the differential hit -318 mV and the following
orbit got to -336 mV. The power branch engineer reviewed the data and
recommended that FOT continue to monitor the data closely. In the
late afternoon the value had come back to a value of -254 mV, but then
by around 012/2300 GMT it climbed back up to -302 mV. The FOT then
started to terminate supports early to conserve power during
spacecraft night. That remained in effect into the following day and
preliminary passes showed some beneficial results. However, the
differential did not subside long and dropped back to -302 mV.
The FOT hoped that as the beta angle improved the phenomena would go
away. However, by Friday (DOY 014) it was apparent that the
differential voltage was not going to stop moving more negative. It
reached -380 mV and the decision was made to go to VT-7. Strict
guidelines were given to the ops crew, so that an overcharging
condition did not occur. The differential came down immediately in VT-
7 and performed nominally, so the batteries remained in VT-7 into the
weekend
The FOT also continued their CMS software acceptance testing this
week. The goal for completion is no later than end of January 2005.
MEETINGS
The FOT met with the NASA power branch engineers on 14 January 2005 to
discuss the short and long term plans to manage the differential
voltage on battery 3.
FUTURE SIGNIFICANT EVENTS
The next UARS Yaw slew is scheduled for 12 February 2005 (DOY 043).
This maneuver will be a Forward to Reverse Flight maneuver (Northern
Hemisphere viewing).
Attachments: Appendix A, Real-time Command Sheets
Appendix B, Out-Of-Limits & ALERT Occurrences
Appendix C, Clock & Solar Array Rate Corrections
Appendix D, UARS Battery Performance Data
Appendix E, UARS Anomaly Reports
APPENDIX A
REAL-TIME COMMAND SHEETS
Week ending 14 January 2005
ORBIT AOS NO. SUBSYS REASON
----- --- --- ------ ------
72969 009/2239 05-005 HALOE POWER OFF (YAW)
72980 010/1656 05-006 OBC/CLK CLK ADJ FR 0.0 TO -20.6 MSEC/DAY
72984 010/2206 05-007 SUSIM POWER OFF
72984 010/2312 05-008 SOLSTICE FULLTIME TO DAY-ONLY OPS
72986 011/0237 05-009 HRDI HRDI DAY ONLY TO LOW POWER
72999 011/2203 05-010 WINDII B/U A OFF
73003 012/0454 05-011 OBC/CLK CLK ADJ FR -20.6 TO 0.0 MSEC/DAY
73009 012/1431 05-013 MACS YAW REV TO FWD
73009 012/1431 05-012 MPS MLS HEATER ACTIONS DISA
73009 012/1509 05-012 MPS MLS HEATER ACTIONS DISA
73010 012/1557 05-013 MACS YAW REV TO FWD
73017 013/0355 05-014 MPS MLS HEATER ACTIONS ENAB
73028 013/2108 05-015 MPS PMON ACTION 23 CLEAR/ENABLE
73040 014/1631 05-016 MPS VT L6 TO L7
APPENDIX B
OUT-OF-LIMITS & ALERTS OCCURRENCES
Week ending 14 January 2005
The following Out-Of-Limits occurrences were detected:
MNEMONIC STATE DESCRIPTION ORBITS
-------- ----- ----------- ------
-None this report period.
The following ALERT occurrences were detected:
MNEMONIC DESCRIPTION ORBITS
-------- ----------- ------
OBSPMACENA23 PMON ACTION 23 OOL 73008
OBSPMGPOOL31 PMON GROUP 31 OOL 73008
APPENDIX C
CLOCK & SOLAR ARRAY RATE CORRECTIONS
Week ending 14 January 2005
CLOCK DRIFT RATE ADJUSTMENTS
ORBIT TIME CLOCK RATE CHANGE
----- ----- -----------------
72980 010/1708 CLK ADJ FR 0.0 TO -20.6 MSEC/DAY
73003 012/0454 CLK ADJ FR -20.6 TO 0.0 MSEC/DAY
APPENDIX D
UARS BATTERY PERFORMANCE DATA
Week ending 14 January 2005
07 January 2005 - GMT Day 007 Beta = 22.2 deg, SA Pos = 269 deg
DIFF V (mV) TEMP (C) CURR (amp) EON V AVE C/D AVE
BAT MAX/MIN MAX/MIN MAX/MIN MIN RATIO DOD(%)
--- ------- -------- ---------- ----- ------- ------
1 -700.0/-700.0 -3.05/-4.31 +00.0/+00.0 07.0 0.00 0.0
2 22.4/ -33.6 +6.44/+5.47 +29.6/-14.0 26.2 1.04 20.0
3 -11.2/-190.4 +5.15/+3.87 +28.0/-13.2 26.2 1.03 19.0
14 January 2005 - GMT Day 014 Beta = 08.3 deg, SA Pos = 269 deg
DIFF V (mV) TEMP (C) CURR (amp) EON V AVE C/D AVE
BAT MAX/MIN MAX/MIN MAX/MIN MIN RATIO DOD(%)
--- ------- -------- ---------- ----- ------- ------
1 -700.0/-700.0 -3.05/-4.31 +00.0/+00.0 07.0 0.00 0.0
2 67.2/ 00.0 +6.43/+4.82 +28.0/-12.8 26.4 1.03 18.9
3 -33.6/-313.6 +4.50/+2.91 +26.0/-11.2 26.4 1.04 17.5
V/T LEVEL CHANGES
ORB# AOS TIME LVL FR-TO
----- -------- ---------
73040 014/1631 LV6 -> LV7
APPENDIX E
UARS ANOMALY REPORTS
Week ending 14 January 2005
NEW ANOMALY REPORTS GENERATED
AR NO. SUBSYS ORBIT TIME CDS PROBLEM/DATA LOSS
------ ------ ----- ---- --- -----------------
05-001 FOT 72997 011/1914 30832 Generic Late Acquisition
05-002 MPS 73008 012/1251 NA BATT 3 DiffV High
ANOMALY CLOSURE INFORMATION RECEIVED
AR NO. SUBSYS ORBIT TIME CDS PROBLEM/DATA LOSS
------ ------ ----- ---- --- -----------------
-None this report period.
ANOMALY INVESTIGATION REPORTS GENERATED
AIR NO. SUBSYS ORBIT TIME CDS PROBLEM/DATA LOSS
------ ------ ----- ---- --- -----------------
-None this report period.
OPEN ANOMALY REPORTS
AR NO. SUBSYS ORBIT TIME CDS PROBLEM/DATA LOSS
------ ------ ----- ---- --- -----------------
05-001 FOT See List Jan 05 30832 Generic Late Acquisition
05-002 MPS 73008 012/1251 NA BATT 3 DiffV High