UARS Weekly Status Report

02 May 2003




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                UARS WEEKLY STATUS REPORT - 02 May 2003

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

Nothing received.

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

SUSIM successfully gathered all of its daily mid resolution, weekly
offset, and occultation scans this past week during periods of UARS
telemetry.  The solar pointing provided by the SSPP in closed loop
pointing mode has been superb.

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

Nothing received.

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

     The PEM web site has moved.  It has a new URL.  Access the PEM web site
using http://wwwpem.space.swri.edu.  The PEM data from the GUVI conjunction
periods has moved to http://wwwpem.space.swri.edu/guvi-pem.html.

     Level 2 PEM HEPSA data files are being reprocessed for submission to the 
DAAC.  This data has been designated as version 2; however, there is no format
difference from the version 1 data format.  Version 2 HEPSA data is being 
generated because it was discovered that there exists processing errors within
some of the HEPSA version 1 data files.  Thus, if you are using any HEPSA
version 1 data files from the DAAC, please replace them with the version 2
data files.  Currently, HEPSA data between 1991274 and 2001365 has been 
reprocessed and archived at the GSFC DAAC.  SwRI is working on reprocessing
data PEM for 2002.

     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 the first conjunction period show spatial
regions that both GUVI and PEM sampled when aurora was present.  Separation
is several minutes to 10's of minutes when both instruments saw aurora. 
PEM has seen no aurora during the second conjunction period.  Due to a 
spacecraft anomaly, no PEM data was collected during the third conjunction 
period.

     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.

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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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WINDII
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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.
                  
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FOT
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                           REPORTING PERIOD

This report covers 19 April 2003 (Orbit 63465, GMT Day 109) through 25
April 2003 (Orbit 63570, GMT Day 115).


                         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         110/0021      63480     POWER OFF
       PEM           110/1406      63489     AXIS 1 POWER ON


The  beta  angle  ranged between the angles of 55.1  degrees  to  69.8
degrees  for  this  report period.  The beta angle is  now  increasing
towards a maximum angle of 70 degrees on 26 April 2003 (DOY 116).

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 1.26 to 1.27 degrees C.  Additional
battery  performance data for each battery on 18 April  and  25  April
2003 are provided in Appendix D.

The  clock  error  ranged from -7.2 to 10.3 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       =    02
    PEM       =    01
    WINDII    =    01
    HALOE     =    01



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

    FOT  =    04

Two  (2) Anomaly Reports remained OPEN at the end of this report period
(see Appendix E).


                        GROUND SYSTEM OPERATION

Four  (4) 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 ground system problems experienced last weekend have prompted the
replacement of UARS CISCO switch one.  This will be performed on
Tuesday of next week, with the existing switch 2 left in place.  This
should eliminate the problems that were seen regarding the bad ports
and provide more stability to the UARS network.

The FOT also received the delivery of both the WAIT statement fix and
the status buffer code.  This code will be installed on the prototype
after the switch is replaced.  Once installed it should only take a
day to test the functionality and report back to the Raytheon
sustaining engineering team.

The tape drive that was also found to be malfunctioning last week has
also been replaced.  This means that the backups of the ground system
files can resume.  New software is also on order to make these backups
more reliable and should be installed sometime in the next three
weeks.

                               MEETINGS


The  FOT attended the weekly UARS DRB on 22 April 2003, to review  the
open  DRs  and  discuss  the  details of  the  next  Eclipse  software
delivery.


                       FUTURE SIGNIFICANT EVENTS

The  next UARS Yaw slew is scheduled for 16 May 2003 (DOY 136).   This
maneuver  will  be  a  Forward to Reverse  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 25 April 2003


ORBIT   AOS        NO.      SUBSYS      REASON
-----   ---        ---      ------      ------
63480   110/0021   03-096   HALOE       POWER OFF
63487   110/1040   03-097   OBC/CLK     CLK ADJ FR 0.0 TO 20.6 MSEC/DAY
63489   110/1406   03-098   PEM         AXIS 1 POWER ON
63563   115/1211   03-099   OBC/CLK     CLK ADJ FR 20.6 TO 41.2 MSEC/DAY
63565   115/1503   03-100   WINDII      CLEAR ERROR CODE E03



                              APPENDIX B
                  OUT-OF-LIMITS & ALERTS OCCURRENCES
                       Week ending 25 April 2003

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 25 April 2003

                     CLOCK DRIFT RATE ADJUSTMENTS

ORBIT          TIME                   CLOCK RATE CHANGE
-----          -----                  -----------------
63487          110/1045               CLK ADJ FR 0.0 TO 20.6 MSEC/DAY
63563          115/1215               CLK ADJ FR 20.6 TO 41.2 MSEC/DAY







                              APPENDIX D
                     UARS BATTERY PERFORMANCE DATA
                       Week ending 25 April 2003

     18 April 2003 - GMT Day 108 Beta = 48.9 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  -190.4/-224.0  -3.68/-4.94  +00.0/+00.0  08.3      0.000     0.0
2   +11.2/-145.6  +5.47/+3.55  +25.2/-15.2  25.4      1.040    20.0
3   +22.4/-44.8   +4.51/+2.92  +24.8/-15.2  25.4      1.030    19.8


     25 April 2003 - GMT Day 115 Beta = 69.8 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  -207.2/-229.6  -3.05/-3.99  +00.0/+00.0  08.3      0.000    0.0
2   +05.6/-22.4   +3.23/+1.97  +16.8/-15.2  26.4      1.060    16.3
3   +16.8/-22.4   +2.60/+1.34  +16.8/-15.2  26.4      1.050    16.1

     V/T LEVEL CHANGES
ORB#           AOS TIME   LVL FR-TO
-----          --------   ---------
-None this report period.

                              APPENDIX E
                         UARS ANOMALY REPORTS
                       Week ending 25 April 2003

                     NEW ANOMALY REPORTS GENERATED
AR NO.    SUBSYS    ORBIT   TIME      CDS       PROBLEM/DATA LOSS
------    ------    -----   ----      ---       -----------------
03-015    FOT       63493   110/2015  30832     Generic Late Acquisition & WS
                                                  Reboot
03-016    FOT       63505   111/1550  NA        Server 1 Tape Drive Install 
03-011    FOT       63565   115/1541  30832     Generic Late Acquisition
03-011    FOT       63569   115/2225  30832     Generic Late Acquisition

                 ANOMALY CLOSURE INFORMATION RECEIVED
AR NO.    SUBSYS    ORBIT     TIME      CDS       PROBLEM/DATA LOSS
------    ------    -----     ----      ---       -----------------
03-009    FOT       63069     082/1624  N/A       Invalid COP Status
03-013    FOT       63368     102/1340  NA        Eclipse Network Issues
03-011    FOT       See List  April 03  30832     Generic Late Acquisition

                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
------    ------    -----     ----      ---       -----------------
03-015    FOT       63493     110/2015  30832     Generic Late Acquisition& WS
                                                  Reboot
03-016    FOT       63505     111/1550  NA        Server 1 Tape Drive
                                                  Install