UARS Weekly Status Report

8 April 2005




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                UARS WEEKLY STATUS REPORT -  8 April 2005

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***********
SOLSTICE
***********

SOLSTICE resumed normal operations this week (doy 096) after performing 
day only operations since the yaw maneuver. Otherwise, the instrument 
continues to perform well, taking solar data on all available orbital 
tracking periods. An average of 60% of data were returned this week 
accounting for 435 minutes of solar observing time per day.

***********
SUSIM
***********

Nothing received.

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PEM
***********

     HEPSA data files are version 2.  Currently, HEPSA data between 1991274 
and 2004299 has been reprocessed and archived at the GSFC DAAC.  HEPSA data
between 2004300 and 2004359 are currently waiting archival at GSFC DAAC.  
HEPSA data between 2004360 and 2004366 are currently being processed. 

     MEPS data files are version 1.  Processed MEPS data files at the DAAC 
archive are between 1991274 and 2004309.  MEPS data between 2004330 and 2004359 
are currently waiting archival at GSFC DAAC.

     PEM continues to receive NMC data files from NOAA.  NMC host machine
changed during mid-January which caused some NMC data transfer failures; 
however, this situation was corrected and recovery completed with the 
assistance of Roger Lin at NOAA.  No problems have been encountered since 
updates have occurred.

     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.

     PEM has received a request for data from the super storm of November
2004.  The Dst value showed sudden commencement early on November 7, 2004
reaching a Dst value of about -380 gamma early on November 8, 2004.
PEM was not active at that time and became active late on November 8, 2004
in day only mode.  A second peak of about -280 gamma was observed on November 
11, 2004.  PEM became active in day-light only mode late on November 8.  PEM
survey spectrograms for November 8-18 of 2004 may be found at:
http://climatology.space.swri.edu/UARS_images_fromRudy.html


*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.

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HALOE 
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Nothing received.

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MLS
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Nothing received.

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HRDI
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Nothing received.

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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.

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CDHF
***********

Nothing received.
                  
***********
FOT
***********

                           REPORTING PERIOD

This report covers 26 March 2005 (Orbit 74098, GMT Day 085) through 
02 April 2005 (Orbit 74203, GMT Day 091).


                         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
       PEM           087/0424      74131     POWER ON / DAY ONLY
       HRDI          087/2132      74142     POWER ON / DAY ONLY
       PEM           090/1538      74183     POWER OFF
       HRDI          090/1538      74183     POWER OFF

The beta angle ranged between the angles of 17.1 degrees to 43.1
degrees for this report period.  The beta angle is now increasing
towards a maximum angle of 65 degrees on 09 April 2005 (DOY 099).

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 4.49 to 3.82 degrees C.  Additional
battery performance data for each battery on 21 March 2005 and 01
April 2005 are provided in Appendix D.

The clock error ranged from 10.9 to -11.7 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         =    00

The following real-time command sheets were executed for the listed
operational element(s) during this report period (see Appendix A).

    FOT       =    12
    PEM       =    02
    HRDI      =    02
    WINDII    =    01

UARS Anomaly Reports initiated during this report period are listed in
Appendix E and summarized below.

    FOT       =    01

One (1) Anomaly Report 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

For most of the week the FOT continued to operate the batteries at the
VT-6 charge rate.  However, as the beta angle increased and the power
available profile increased, the FOT noticed high C/D ratios even at
VT-6.  PEM, HRDI and SOLSTICE were operated in their day-only mode to
try to minimize this higher charge, but had a minimal effect on the
C/D ratio.  Also, battery 2 was still operating near 10C, so the
decision was made on day 090 on the 1504 event to go down to VT-5.  In
order to drop VT levels PEM and HRDI were both removed from day-only
operations.  The spacecraft will remain in this configuration over the
weekend and the FOT will analyze the batteries performance at this
level next week.

This week the FOT began its tests of the solar array drive on 30 March
2005 and 01 April 2005.  Both sides of the drive were used in order to
characterize their performance.  The drive was moved 20 degrees in
either direction, however the results from these test runs were
inconclusive.  More testing will be done next week to try to isolate
the nature of the problem.

Also this week, UARS began using this new SMA functionality starting
on 28 March 2005.  However, given the current battery issues the
instrument load has been minimal.  Hopefully, the batteries will
stabilize next week and some instruments will be able to be turned on.

                               MEETINGS

The FOT held a meeting with the NASA power branch on 29 March 2005 to
discuss the current battery situation and the best course of action
for the next few days.  It was decided at this meeting, to go to VT-5
the following day to reduce the battery 2 temperature and C/D ratio.

                       FUTURE SIGNIFICANT EVENTS

The next UARS Yaw slew is scheduled for 29 April 2005 (DOY 119).  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 01 April 2005

ORBIT   AOS        NO.      SUBSYS      REASON
-----   ---        ---      ------      ------
74129   087/0104   05-095   OBC/CLK     CLK ADJ FR 0.0 TO -20.6 MSEC/DAY
74131   087/0424   05-096   PEM         POWER ON / DAY ONLY
74142   087/2132   05-097   HRDI        POWER ON / DAY ONLY
74146   088/0420   05-098   OBC/CLK     CLK ADJ FR -20.6 TO 0.0 MSEC/DAY
74156   088/2055   05-099   OBC/CLK     CLK ADJ FR 0.0 TO -20.6 MSEC/DAY
74157   088/2203   05-100   WINDII      POWER ON / OFF
74159   089/0057   05-100   WINDII      POWER ON / OFF (PWR MGMT)
74160   089/0237   05-100   WINDII      POWER ON / OFF (PWR MGMT)
74167   089/1436   05-101   TMON        LOAD RTS 8 & 9 DIS TMONS
74167   089/1436   05-102   PMON        WINDII PMONS 15 & 17
74168   089/1540   05-103   SADDE       MOVE DRIVE B (ENGR TEST)
74169   089/1755   05-104   PMON        WINDII PMONS 14 & 16
74171   089/1944   05-105   SADDE       MOVE DRIVE A (ENGR TEST)
74174   090/0054   05-106   OBC/CLK     CLK ADJ FR 20.6 TO 0.0 MSEC/DAY
74183   090/1504   05-107   MPS         MPS L6 -> VT-5
74183   090/1538   05-108   PEM/HRDI    PEM / HRDI POWER OFF
74197   091/1429   05-109   SADDE       SADDE TEST - A-SIDE
74198   091/1459   05-110   SADDE       SADDE TEST - B-SIDE

                              APPENDIX B
                  OUT-OF-LIMITS & ALERTS OCCURRENCES
                       Week ending 01 April 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
--------     -----------                          ------
-None this report period.

                              APPENDIX C
                 CLOCK & SOLAR ARRAY RATE CORRECTIONS
                       Week ending 01 April 2005

                     CLOCK DRIFT RATE ADJUSTMENTS

ORBIT          TIME                   CLOCK RATE CHANGE
-----          -----                  -----------------
74129          087/0111               CLK ADJ FR 0.0 TO -20.6 MSEC/DAY
74146          088/0430               CLK ADJ FR -20.6 TO 0.0 MSEC/DAY
74156          088/2058               CLK ADJ FR 0.0 TO 20.6 MSEC/DAY
74174          090/0117               CLK ADJ FR 20.6 TO 0.0 MSEC/DAY

                              APPENDIX D
                     UARS BATTERY PERFORMANCE DATA
                       Week ending 01 April 2005

     25 March 2005 - GMT Day 084 Beta = 13.5 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  -2.11/- 3.05  +00.0/+00.0  06.9     0.00      0.0
2    212.8/  89.6 +13.49/+12.10  +29.6/-14.8  26.7     1.14     18.6
3     00.0/-593.6  +6.44/+ 5.79  +24.0/-11.2  26.6     1.07     16.1

     01 April 2005 - GMT Day 091 Beta = 43.1 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  -3.68/-4.94   +00.0/+00.0  06.9     0.00      0.0
2    291.2/  89.6  +7.09/+5.79   +26.8/-14.4  25.8     1.07     15.4
3     78.4/-700.0  +2.60/+1.97   +20.8/-12.0  25.8     1.02     13.2


     V/T LEVEL CHANGES
ORB#           AOS TIME   LVL FR-TO
-----          --------   ---------
74183          090/1504   LV6 -> LV5


                              APPENDIX E
                         UARS ANOMALY REPORTS
                       Week ending 01 April 2005

                     NEW ANOMALY REPORTS GENERATED
AR NO.    SUBSYS    ORBIT     TIME      CDS       PROBLEM/DATA LOSS
------    ------    -----     ----      ---       -----------------
05-012    FOT       74160     089/0334  30832     Generic Late Acquisition

                 ANOMALY CLOSURE INFORMATION RECEIVED
AR NO.    SUBSYS    ORBIT     TIME      CDS       PROBLEM/DATA LOSS
------    ------    -----     ----      ---       -----------------
05-020    PEM       74026     080/0503  N/A       ZEPS/NEPS turned off
05-021    MPS       74038     080/2332  N/A       BAT 3 DIFFV -694 R-HI
05-022    OBC       74083     084/0041  N/A       S/W Stored Cmd Error

                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
------    ------    -----     ----      ---       -----------------
05-012    FOT       See List  Mar 05    30832     Generic Late Acquisition