UARS Weekly Status Report

09 August 2002




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                UARS WEEKLY STATUS REPORT - 09 AUG 2002

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

Nothing received.

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

SUSIM was turned off for the yaw-around on 7/31 and was repowered on
8/5.  Data taking resumed about 40 hours after power on because the
instrument was too cold.  Otherwise, SUSIM successfully performed its
daily mid-resolution and MgII solar scans during periods of predicted
UARS telemetry.

***********
ACRIM
***********

Nothing received.

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

PEM continues to work with the GUVI team on the diagnosis of data from
the first conjunction period.  Analysis of the two conjunction passes showed
that the aurora as detected by GUVI was at higher latitude than UARS.  
GUVI images from other times from this conjunction period show spatial
regions that both GUVI and PEM sampled when aurora was present.  Separation
is several minutes to 10's of minutes.  A PEM representative is attending
the TIMED workshop August 7-9.

PEM data from the second GUVI-PEM conjunction is now being processed.

PEM continues to receive NMC data files from NOAA.  No problems have
been encountered.  NOAA has changed the binary structure of the NMC data and
PEM is now receiving two data streams, one in the original VAX format and the
other from their new binary format.

*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.

***********
WINDII
***********

WINDII experienced difficulties with the new ECLIPSE commanding
system, which appeared to be resolved, in that WINDII operations
were successfully achieved. However, we subsequently learned
that no science data were being produced. For the next turn-on,
scheduled August 10, we have planned  tests to help determine
whether this problem originates with the uploads normally sent.

***********
MPG
***********

The MPG continues to serve as the point-of-contact for UARS
instrument operations to support re-engineering of the UARS
Mission Operations Concept to develop capabilities for the
Science Traceability Mission. The UARS Monthly Status Review 
Meeting was held on August 07, 2002.

Daily processing of instrument Daily Activity Plans continues
with no problems.

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

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


                           REPORTING PERIOD

This report covers 27 July 2002 (Orbit 59468, GMT Day 208) through  02
August 2002 (Orbit 59571, GMT Day 214).


                         SPACECRAFT OPERATION

The observatory is now in Reverse Flight (Northern Hemisphere viewing)
and   is  performing  nominally  under  two-battery  operations.   The
instrument operational changes were:


                    INSTRUMENT OPERATIONAL CHANGES

       Instrument    Time          Orbit     Comment
       HRDI          210/1643      59507     POWER ON / DAY ONLY
       HRDI          210/1824      59508     DAY ONLY TO LOW PWR
       HALOE         210/2157      59511     POWER OFF
       HRDI          210/2341      59512     POWER ON / DAY ONLY
       PEM           211/2156      59526     POWER OFF
       SOLSTICE      212/2155      59541     POWER OFF
       SUSIM         212/2155      59541     POWER OFF

A Forward-to-Reverse Yaw Around maneuver (number 111) was successfully
executed in Orbit 59566 beginning 214/14:13:17Z and completing at
214/14:50:27Z on 02 August 2002.  All instruments were in their off or
standby mode (including HRDI and PEM).  Due to the SA position at 269
degrees, the effective night length of the spacecraft after the
maneuver was approximately 57.07 minutes.  Post maneuver analysis of
data indicate that during the Yaw Around, the end-of-night load bus
voltage was 25.14 volts and the average depths of discharge (DODs) on
Batteries 2 and 3 were approximately 20.51 and 20.16 percent
respectively.  The next (reverse-to-forward) YAW is scheduled for 04
September 2002 (DOY 247).

The  beta  angle  ranged between the angles of  19.4  degrees  to  0.0
degrees  for  this  report period.  The beta angle is  now  increasing
towards a maximum angle of 45 degrees on 19 August 2002 (DOY 231).

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 1.39 degrees C.  Additional
battery  performance data for each battery on 26 July  and  02  August
2002 are provided in Appendix D.

The  clock  error  ranged from 9.9 to 10.2 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       =    03
    HRDI      =    03
    HALOE     =    01
    PEM       =    01
    SOLSTICE  =    01
    SUSIM     =    01


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

    FOT  =    03

Four (4) Anomaly Report remained OPEN at the end of this report period
(see Appendix E).


                        GROUND SYSTEM OPERATION

Three  (3) operational support problems 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


The Raytheon development team has delivered a new database patch which
should fix the status buffer display problem.  This patch will be
tested this week on the prototype system.

The FOT is also working with the WINDII instrument team to determine
the source of their instrument turn on problem.  It was recently
discovered, by the WINDII team, that WINDII's science data has not
been captured correctly since February.  There were discrepancies
found in their POCC resident microloads during Eclipse transition and
the investigation has been focused on determining if these loads are
correct.

                               MEETINGS
-None this report period

                       FUTURE SIGNIFICANT EVENTS


The  next UARS Yaw slew is scheduled for 04 September 2002 (DOY  247).
This  maneuver will be a Reverse to Forward Flight maneuver  (Southern
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 02 August 2002

ORBIT   AOS        NO.      SUBSYS      REASON
-----   ---        ---      ------      ------
59507   210/1643   02-259   HRDI        POWER ON / DAY ONLY
59508   210/1824   02-260   HRDI        DAY ONLY TO LOW POWER
59511   210/2157   02-261   HALOE       POWER OFF
59512   210/2341   02-262   HRDI        POWER ON / DAY ONLY
59526   211/2156   02-263   PEM         POWER OFF
59527   211/2340   02-264   OBC/CLK     CLK ADJ FR 0.00 TO 20.6 MSEC/DAY
59541   212/2155   02-265   SOLSTICE    POWER OFF
59541   212/2155   02-266   SUSIM       POWER OFF
59546   213/0626   02-268   OBC/CLK     CLK ADJ FR 20.6 TO 0.00 MSEC/DAY
59565   214/1234   02-268   OBC         YAW  FWD TO REV
59566   214/1439   02-268   OBC         YAW

                                   
                                   
                              APPENDIX B
                  OUT-OF-LIMITS & ALERTS OCCURRENCES
                      Week ending 02 August 2002

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 02 August 2002

                     CLOCK DRIFT RATE ADJUSTMENTS

ORBIT          TIME                   CLOCK RATE CHANGE
-----          -----                  -----------------
59527          211/2345               CLK ADJ FR 0.00 TO 20.6 MSEC/DAY
59546          213/0626               CLK ADJ FR 20.6 TO 0.00 MSEC/DAY
                              APPENDIX D
                     UARS BATTERY PERFORMANCE DATA
                      Week ending 02 August 2002


     26 July 2002 - GMT Day 207 Beta = 28.1 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  -157.0/-168.0 -3.30/-4.24  +00.0/+00.0 08.5      0.000     0.0
2  + 11.2/- 69.6 +6.44/+5.15  +27.5/-17.9  27.8     1.030    21.8
3  + 22.4/- 56.0 +5.21/+3.87  +26.7/-17.6  27.7     1.020    21.4


     02 August 2002 - GMT Day 214 Beta = 0.0 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  -157.0/-168.0 -3.05/-4.62  +00.0/+00.0 08.5     0.000     0.0
2  + 11.2/- 69.6 +5.47/+4.08  +27.0/-13.4 23.8     1.090    20.4
3  + 22.4/- 50.4 +4.51/+2.92  +25.7/-13.5 23.8     1.080    20.0


     V/T LEVEL CHANGES
ORB#           AOS TIME   LVL FR-TO
-----          --------   ---------
59565          214/1238   L5 -> L6


                              APPENDIX E
                         UARS ANOMALY REPORTS
                      Week ending 02 August 2002


                     NEW ANOMALY REPORTS GENERATED
AR NO.    SUBSYS    ORBIT     TIME      CDS       PROBLEM/DATA LOSS
------    ------    -----     ----      ---       -----------------
02-042    FOT       59503     210/0959  N/A       TMON 01 tripped
02-039    FOT       59526     211/2156  30832     Generic Late Acquisition
02-043    FOT       59571     214/2308  31245     Data Drop Out

                 ANOMALY CLOSURE INFORMATION RECEIVED
AR NO.    SUBSYS    ORBIT     TIME      CDS       PROBLEM/DATA LOSS
------    ------    -----     ----      ---       -----------------
-None this report period.

                ANOMALY INVESTIGATION REPORTS GENERATED
AR NO.    SUBSYS    ORBIT     TIME      CDS       PROBLEM/DATA LOSS
------    ------    -----     ----      ---       -----------------
-None this report period.

                         OPEN ANOMALY REPORTS
AR NO.    SUBSYS    ORBIT     TIME      CDS       PROBLEM/DATA LOSS
------    ------    -----     ----      ---       -----------------
02-039    FOT       See List  July      30832     Generic Late Acquisition
02-041    FOT       59279     195/1156  N/A       TMON 01 tripped
02-042    FOT       59503     210/0959  N/A       TMON 01 tripped
02-043    FOT       59571     214/2308  31245     Data Drop Out