HUBBLE SPACE TELESCOPE - Continuing to collect World Class
Science
DAILY REPORT #4852
PERIOD COVERED: 5am May 22 - 5am May 26, 2009 (DOY
142/0900z-146/0900z)
OBSERVATIONS SCHEDULED
S/C/FGS 11457
Verify Guide Star Acquisition with Continuing FGSs
After the shuttle deploys HST at the end of SM4 and at the
beginning of
SMOV4, it will be necessary to test and demonstrate HST's
ability to
acquire guide stars with the FGSs. This is a major
pre-requisite for all
observations by HST's SIs when precision pointing under
guide star
control is needed. This proposal will test the ability of
each of the
unreplaced FGSs to acquire a primary guide star while
another FGS
acquires a secondary guide star. After acquiring the guide
star pair,
HST will track these stars in finelock for approximately
10 minutes.
When possible, use guide stars that have been successfully
acquired and
tracked in the past.
S/C/ACS 11365
Load and Dump Onboard Memory
This proposal is a test and verification of the ACS dump
of memory
capability. Areas of Control Section (CS) to dump include:
EDAC RAM,
EEPROM, and CS PROM (with the CS in Operate). Areas of MIE
memory to
dump include: MIE RAM and MIE PROM (with the MIE in
Operate). Note that
the MIE memory must first be copied to CS buffer RAM as
images, which
are then dumped.
S/C 11364
Vehicle Disturbance Test
The purpose of the VDT is to measure and characterize uncompensated
environmental disturbances acting upon the HST during
normal operation.
The VDT is a passive test (not a forced-response test)
used to obtain
signatures for both externally induced (e.g. SCM, SA-3,
SSM thermal
gradients) and internally induced (e.g. HGA, RWA, COS and
WFC3
mechanisms) disturbances affecting HST LOS pointing. The
disturbances
observed will be used as the nominal on-orbit disturbances
in pointing
control simulations until the next VDT is run.
The test occurs after release, and most of the VDT can be
run during the
BEA period. The -V1 sunpoint portion of the VDT usually
occurs after the
BEA period is complete. The VDT shall consist of two
separate tests that
need not occur consecutively. The overall duration of the
VDT is at
least 13 orbits of spacecraft time including (1) at least
8 orbits at
+V3 sunpoint after achieving thermal equilibrium (at least
36-hours at
+V3 sunpoint) and three out of 8-orbits have RWA Friction
Compensation
turned Off, and (2) at least 5 orbits at -V1 sunpoint (all
or part of
this segment have RWA Friction Compensation turned Off).
At the
beginning of each test, the attitude control law gains are
switched to
maneuver gains, and the gyros are commanded to low mode.
The nominal
attitude control law configuration will be restored at the
end of each
test.
Each test is initiated via SMS execution of stored program
macros in the
HST flight computer to switch the attitude control law
gains to
low-bandwidth maneuver gains, command the gyros into low
mode, terminate
Velocity aberration and parallax (VAP) processing, and
manage the status
of on-board RWA Friction Compensation. The nominal
attitude control law
configuration will be restored at the end of each test via
SMS execution
of stored program macros. The stored program command
macros are
developed specifically for the VDT by the Flight Software
and Pointing
Control System groups.
S/C/COS 11353
COS Dump Test and Verification of COS
Memory Loads
This proposal is a test and verification of the COS dump of memory
capability. Areas of Control Section (CS) to dump include:
EXEC RAM,
EEPROM, and CS PROM (with the CS in Operate). Areas of DIB
memory to
dump include: DIB RAM and DIB PROM (with the DIB in
Operate). Areas of
DCE memory to dump include: the DCE code image. Note that
the DIB and
DCE memory must first be copied to CS buffer RAM as
images, which are
then dumped. Supports Activity COS-02
FLIGHT OPERATIONS SUMMARY:
Significant Spacecraft Anomalies: (The following are
preliminary reports
of potential non-nominal performance that will be
investigated.)
HSTARS:
11845 - During FGS-2 ITS test at 142/11:48 - Trans mode
failed with no
S-curve detected in y-axis. FGS-2 did achieve
Fine Lock and LOS scan was
also successful.
11847 - WFC3 safed on IMEB1ST @ 145/13:02z
COMPLETED OPS REQUEST:
18436-2 - Open COS FUV DVA door @ 142/15:26z
18441-0 - VDT Macro Installation - IP-170 @ 143:10:50z
18442-0 - Execute Vehicle Disturbance Test - IP-170
Section B and C @ 144/01:34z
18451 0 - Recover WFC3 to Boot @ 145/13:50z
18444-1 - Reset WFC3 setpoints after recovery @ 145/14:04z
18452-4 - Recover WFC3 from Boot to Operate @ 145/16:16z
18448-0 - ACS CEB-R ASIC FSW Timing Pattern Update @
146/16:22z
18446-1 - Clear ACS WFC TEC Event Flag 8 @ 145/17:22z
COMPLETED OPS NOTES: (None)
SCHEDULED SUCCESSFUL
FGS GSAcq 19 19
FGS REAcq 00 00
OBAD with Maneuver 22 22
SIGNIFICANT EVENTS:
Flash Reports:
-COS successfully transition to operate at ~ 142/10:32.
The FUV DCE
successfully transition to operate at 142/10:52. No limit
violation
observed and the instrument is performing nominally.
COS internal pressure is currently at 3.5x10-6 torr, we
are on schedule
for opening the FUV DVA door at 11:00am EST Friday
morning.
-The COS and ACS memory
that was collected was dumped from the SSR
at 142/13:40z, these dumps were analyzed and report to be
as expected.
-The COS FUV door was successfully opened at 142/15:22.
All power and position
telemetry was as expected. A small increase in pressure
was measured by the COS internal
and ESM ion gauges.
-VDT data collection successful. The Vehicle Disturbance
Test at the +V3
sunpoint attitude was successfully completed at
2009/144/01:34 with the
nominal gains restored to the vehicle control law. An
LBBIAS was
uplinked to the vehicle to ensure minimal bias errors at
the following
Guide Star Acquisition. That subsequent acquisition at
144/03:45
succeeded.
-At 145/1100 WFC3 recovery from Protect Safe mode began
via
stored commanding. At 145/1302 during the transition to
Protect Operate,
the instrument safed as a result of a limit check
violation of an
SES-collected thermistor on the unpowered MEB.
-WFC3 was recovered to Protect Operate. At 145/1631 WFC3
successfully
intercepted the SMS timeline to dump EEPROM, Exec RAM,
and PROM memory.
SSR playback is currently in progress and the memory
dumps will be analyzed
by the Payload FSW team.
-WFC3 EEPROM, Exec RAM, and PROM memory dumps were
collected via SMS
starting at 145/1631. The SSR playback of these dumps
began at 145/1651.
The Payload FSW team has verified the contents of the
memory dumps are
as expected.
WFC3 remains in Protect Operate.
-The FSW team completed the COS
analysis of the
zero-filled pattern loaded to and dumped from CS Buffer
memory at 145/1700.
In summary, no bit flips in CS Buffer memory were
observed.