********************************************************************
UARS WEEKLY STATUS REPORT - 23 January 1998
********************************************************************
***********
SOLSTICE
***********
SOLSTICE continues to operate normally, collecting solar data on all
available orbital tracking periods and stellar calibration observations,
whenever possible.
***********
SUSIM
***********
SUSIM successfully gathered its normal solar, offset, and occultation
scan data during this past week without apparent problems.
***********
ACRIM
***********
The UARS/ACRIM II experiment continues to function normally in all
respects. The tasks of preparation and submission of ACRIM II Daily
Activity Plans and archiving of raw data has been transferred smoothly from
JPL to the Columbia ACRIM II team, thanks to the assistance of JPL and CDHF
personnel. The ACRIM II results have been brought up to date through 1997
and have been provided to the GSFC and LARC DAAC's for publication.
***********
PEM
***********
PEM/AXIS was active from January 18 through January 22. PEM produced
energy deposition profiles from electrons inverted from the AXIS X-ray
measurements taken during this time.
PEM is awaiting evaluation by GSFC of its proposed activation procedure.
The minimal configuration for PEM AUX activation is the zenith VMAG, MEPS1,
MEPS2, and HEPS1 units, only. This configuration is driven by the capabilities
of the spacecraft OBC and may increase if OBC program area increases. PEM
activation is proposed to be OBC driven when there exists plenty of power to
operate PEM. It is anticipated that the OBC will activate PEM on the daylight
portions of every orbit.
***********
HALOE
***********
HALOE was powered on beginning of day January 23, 1998. All engineering
parameters and science data channels are nominal.
***********
MLS
***********
Nothing received.
***********
HRDI
***********
HRDI is scheduled to turn on 23rd of January and operate thru the 28th of
January.
***********
WINDII
***********
Nothing received.
***********
MPG
***********
Routine processing of instrument Daily Activity Plans continues
with no problems. The MPG continues to assist the Project
Scientist with the scheduling of instrument operations.
***********
CDHF
***********
The CDHF has received a total of 364 CD-ROM requests as of 23-January-1998.
There were four orders received and four orders shipped.
The CDHF previewed DAAC data for HALOE, HRDI, PEM, NMC, and UKMO
for the month of November 1997.
The CDHF successfully tested the Attitude Extraction Software V7.2.
Output Version 8 product were analyzed and approval was given to promote
the software to production.
The CDHF forwarded a list of (YAW +1) UARS DAYS that need to be reprocessed
with the new Attitude Extraction Software V7.2 to Solstice for review. Solstice
has concurred the list is complete and no other days need to be reprocessed.
The CDHF processed current day data through level 3 for all active
instruments. Additionally, CDHF personnel reprocessed: (R)= Requested
(C) = Complete, (F)= Failed (L) = Days remaining to reprocess.
54 days PEM (3.32) PROD (1379R-829C=550L)
77 days MLS (4.90) PROD (1344R-77C-1F=1267L)
128 days ATT (7.2) PROD (128R-128C=0L)
1 day HAL (4.71) TEST (1R-1C=0L)
0 day CLAES (7.0) ENG (17R-1F=17L)
8 days WIN (5.10) ENG (13R-8C=5L)
The CDHF received approval from the MLS group to promote V4.90 to production.
MLS has provided a list of Mission days to be processed.
***********
FOT
***********
REPORTING PERIOD
This report covers 09 January 1998 (Orbit 34597, GMT Day 010) through
16 January 1998 (Orbit 34700, GMT Day 016).
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
PEM 004/1516 34516 ZEPS on
PEM 009/2327 34596 ZEPS off
The beta angle reached a minimum angle of 0.0 degrees on 16 January 1998 (DOY
016). The beta angle is now increasing toward a maximum angle of 72.6 degrees
on 05 February 1998 (DOY 036).
A Forward-to-Reverse Yaw Around maneuver (number 65) was successfully executed
in Orbit 34695 at 13:25:19 UTC on 16 January 1998. The SSPP Instruments
(ACRIM, SOLSTICE, and SUSIM) were enabled. Due to the SA position at 269
degrees, the effective night length of the spacecraft after the maneuver was
48 minutes. Post maneuver analysis of data indicate that during the Yaw
Around, the end-of-night load bus voltage was 25.8 volts and the average
depths of discharge (DODs) on Batteries 2 and 3 were approximately 23.5 and
22.5 percent respectively. The relatively high load bus voltage was the
result of charging at V/T level 6 during the daylight period immediately prior
to the yaw.
Integrated SSPP calibration and alignment data was received from Flight
Dynamics Facility (FDF) on 13 January 1998. The delivered data was verified
and then uplinked to the spacecraft the same day (14 January 1998,
014/21:07:03 UTC, Orbit 34670). The results are shown in Appendix F, Results
of SSPP Alignment Update.
A Rmanually generatedS Stellar Offset maneuver requested by SOLSTICE was
executed on GMT Day 015.
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 24.5 V end-of-night (EON) load bus voltage. Battery
temperatures are stable with a temperature delta between Battery 2 and Battery
3 of 1.3 degrees C. Additional battery performance data for each battery on
10 January 1998 and 16 January 1998 are provided in Appendix D.
The battery V/T 6 charge control level was utilized on 15 January 1998 for two
orbit to observe the effect on end-of-night load sharing. The observatory was
then returned to the V/T 5 charge control level. V/T 6 charge control was used
again for one orbit just prior to the Yaw Maneuver on 16 January 1998 to boost
the battery recharge for the Yaw night. Charge control was returned to VT 5
following the one orbit charge boost.
The clock error ranged from -10.7 to +9.3 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.
% ALERTS = 01
% OUT-OF-LIMITS = 04
The following real-time command sheets were executed for the listed operational
element(s) during this report period (see Appendix A).
% FOT 08
% HALOE 01
UARS Anomaly Reports initiated during this report period are listed in Appendix
E and summarized below.
% FOT none
TRANSPONDER FREQUENCIES:
Transponder A: 97/364 - 2287.496935
Transponder B: 98/014 - 2287.498785
GROUND SYSTEM OPERATION
No operational support problem(s) occurred this period. Anomaly Reports are
included in Appendix E.
The data loss calculations supplied by Data Capture Facility (DCF) from mission
start through UTC Day 98/015 show the observatory data loss to be 20 hours, 41
minutes, 34.260 seconds (an increase of 03.424 seconds since last reported).
This is a 0.0374 percent data loss which equals a 99.9626 percent data capture
for the mission.
The increase of 3.424 seconds occurred over three days as follows:
7 a loss of 0.640 seconds on Day 009 due to a hit in the data,
7 a loss of 2.272 seconds on Day 010 due to a hit in the data, and
7 a loss of 0.512 seconds on Day 012 due to a hit in the data.
No testing of the new CMS software release (R7B1V2) occurred this week.
Operational processing of level-0 telemetry analysis files continues in
parallel on both the UMPGAL (new MPG Alpha machine) and CDHF computer systems.
No level-0 file transfer failures (between CDHF and UMPGAL) occurred this week.
The UARS/TOMS re-engineering team had requested that the UARS I-channel data be
sent to their test system (via the TOMS 511 line) to facilitate development of
the new UARS ground system - re-engineering effort. A message was sent to the
Goddard Com Manager to request that the UARS real-time I-channel data be sent
to the TOMS 511 line, in addition to being sent to the MS 434 line (its normal
configuration). The new data/line configuration should be in place for a period
of 2 to 3 months.
The FOT has finalized the details for participating in the IP return-link
telemetry testing. The FOT was informed MSOCC (Tom Marsh) that the IP
conversion devices will be ready for use by 21 January 1998. The MSOCC DOC
operators have been informed of the special procedures which must be executed
to configure the AP to receive IP data from NASCOM. UARS plans to start
viewing the IP data using a backup AP as soon as the conversion devices are
available.
A test version of UARS FOT Database Version 66 was generated by the FOT on 09
January 1998. The database was modified to accommodate the reduction of the
ATC memory location storage from 1024 commands to 768. A corresponding
modification will temporarily be made to the CMS to allow the generation of an
ATC load for testing with the new database.
SUSIM operations has requested a series of SSPP gridded offset maneuvers to
take place on GMT days 017 through 022. The offsets will utilize the 5 and 10
arcminute intervals, as opposed to the 15 and 30 arcminute intervals.
SOLSTICE has requested two additional Stellar offsets for GMT days 020 and 022.
OTHER SIGNIFICANT EVENTS
Work on the upgrade of the OBC Power Monitor (PMON) software continued. Nearly
completed redesign, and began coding (a small amount of key component coding is
required to verify the feasibility of the planned design, before the redesign
can be completed in its entirety). All coding should be done within two to
three weeks.
Monitoring of the magnetic field model performance continues.
FOT continues to improve a Power Profile for UARS based on the current status
of the Modular Power System.
FOT continues to support the new UARS ground system re-engineering effort.
MEETINGS
No UARS Battery telecon was held this week. The next telecon has not been
scheduled.
FUTURE SIGNIFICANT EVENTS
The next UARS Yaw Around Maneuver is currently scheduled for 25 February 1998.
The UARS orbit altitude is dropping slowly and a drag makeup orbit adjust will
probably be required in mid-1998.
FACILITIES
no change
PERSONNEL CHANGES
no change
Attachments: Appendix A, Real-time Commands 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 F, Results of SSPP Alignment Update
APPENDIX A
REAL-TIME COMMAND SHEETS
Week ending 16 January 1998
ORBIT AOS NO. SUBSYS REASON
----- --- --- ------ -------
34641 012/2339 97-009 HALOE Power OFF
34643 013/0200 97-010 OBC Clk Adj fr 0.00 to 20.6 msec/day
34654 013/2046 97-011 PMON Heater delay to 200 Amp. mins.
34659 014/0343 98-012 OBC Clk Adj fr 20.6 to 0.00 msec/day
34670 014/2104 98-013 SSPP Calibration & alignment update
34681 015/1519 98-014 MPS Batt chrg test
34694 016/1202 98-015 MPS V/T Level change to 6
34695 016/1332 98-016 MPS V/T Level change to 5
34697 016/1721 98-017 MPS Reset BATSOC to 100
_______________________________________________________________
APPENDIX B
OUT-OF-LIMITS & ALERTS OCCURRENCES
Week ending 16 January 1998
MNEMONIC STATE DESCRIPTION ORBITS
--------- ----- ------------ ------
WIEUTEMP Y-LO WINDII EU Temperature 34656-700
SOSTMPRNTRN Y-LO SOLSTICE Temperature Entrance 34696-98
ACTEMPANA2 Y-LO Temp Sensor Electronics 34696-97
QTSISAIF Y-HI SSPP Baseplate by SISA I/F 34697-98
The following ALERT occurrences were detected:
MNEMONIC DESCRIPTION ORBITS
--------- ------------ ------
OBSZ1OOL UFLTR Z1 Residual Exceeded 100 Arcsec 34695
APPENDIX C
CLOCK & SOLAR ARRAY RATE CORRECTIONS
Week ending 016 January 1998
CLOCK DRIFT RATE ADJUSTMENTS
ORBIT TIME CLOCK RATE CHANGE
----- ---- -----------------
34643 013/02:03 (13 Jan 98) from 00.0 to 20.6 msec/day
34659 014/03:48 (14 Jan 98) from 20.6 to 00.0 msec/day
_______________________________________________________________
APPENDIX D
UARS BATTERY PERFORMANCE DATA
Week ending 16 January 1998
10 Jan 1998 - GMT Day 010 Beta = 20.0 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 +728.0/+728.0 -3.05/-4.31 +0.0/ +0.0 18.6 0.000 0.0
2 +5.6/ -78.4 +6.11/+4.83 +32.0/-14.4 25.4 1.030 22.0
3 +89.6/ -5.6 +4.83/+3.55 +30.8/-15.6 25.4 1.024 21.5
16 Jan 1998 - GMT Day 016 Beta = 0.8 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 +728.0/+728.0 -3.05/-4.31 +0.0/ +0.0 18.6 0.000 0.0
2 +106.4/ +0.0 +6.11/+5.15 +32.4/-15.2 24.5 1.019 22.4
3 +89.6/ -11.2 +4.83/+3.87 +31.2/-16.0 24.5 1.017 21.8
V/T LEVEL CHANGES
ORB# TIME LVL FR-TO
----- -------- ----------
34681 015/15:31:21 L5-L6
34683 015/18:39:50 L6-L5
34694 016/12:16:18 L5-L6
34695 016/13:45:51 L6-L5
_______________________________________________________________
APPENDIX E
UARS ANOMALY REPORTS
Week ending 16 January 1998
AR NO. SUBSYS ORBIT TIME TTR PROBLEM/DATA LOSS
------ ------ ----- ---- --- -----------------
None this report period
ANOMALY CLOSURE INFORMATION RECEIVED
AR NO. SUBSYS ORBIT TIME TTR PROBLEM/DATA LOSS
------ ------ ----- ---- --- -----------------
None this report period
(END 1997 AR DATA - ALL 1997 AR CLOSED)
ANOMALY INVESTIGATION REPORTS GENERATED
AIR NO. SUBSYS ORBIT TIME TTR PROBLEM/DATA LOSS
------- ------ ----- ---- --- -----------------
None this report period
_______________________________________________________________
APPENDIX F
Results of SSPP Alignment Update
Week ending 16 January 1998
SSPP calibration and alignment data were uplinked to the spacecraft on 14
January 1998, 014/21:07:03 UTC, Orbit 34670. The results are shown below:
Before the uplink:
SSPP alpha PSS error = -30.3 arcsec (14.8 arcsec sigma)
SSPP beta PSS error = -7.1 arcsec (19.2 arcsec sigma)
After the uplink:
SSPP alpha PSS error = -30.9 arcsec (14.0 arcsec sigma)
SSPP beta PSS error = -5.2 arcsec (18.4 arcsec sigma)
These results show very little change in SSPP pointing during sun tracks.
The new calibration and alignment data has not yet been updated on the CDHF
system, but FDF plans to accomplish this within the next week.