HUBBLE SPACE TELESCOPE - Continuing to collect World Class
Science
DAILY REPORT #4693
PERIOD COVERED: 5am September 10 - 5am September 11, 2008
(DOY 254/0900z-255/0900z)
OBSERVATIONS SCHEDULED
FGS 11212
Filling the Period Gap for Massive Binaries
The current census of binaries among the massive O-type
stars is
seriously incomplete for systems in the period range from
years to
millennia because the radial velocity variations are too
small and the
angular separations too close for easy detection. Here we
propose to
discover binaries in this observational gap through a
Faint Guidance
Sensor SNAP survey of relatively bright targets listed in
the Galactic O
Star Catalog. Our primary goal is to determine the binary
frequency
among those in the cluster/association, field, and runaway
groups. The
results will help us assess the role of binaries in
massive star
formation and in the processes that lead to the ejection
of massive
stars from their natal clusters. The program will also
lead to the
identification of new, close binaries that will be targets
of long term
spectroscopic and high angular resolution observations to
determine
their masses and distances. The results will also be
important for the
interpretation of the spectra of suspected and newly
identified binary
and multiple systems.
FGS 11819
Certifying the SMOV4 FGS AMA Stars with FGS1r
This proposal observes the candidate SMOV4 "AMA
stars" prior to SM4 to
certify which of them are unresolved point sources, and
hence is an
appropriate AMA target. Each target is to be observed in a
1-orbit visit
using FGS1r in its highly angular resolution Transfer mode
with two
exposures. Exposure 1 utilizes a 0.8" scan path with
20 scans which will
provide high S/N for the detection of binary down to ~12
mas, while the
second exposure utilizes a 6" scan path to provide
sensitivity to
putative wide companions.
FGS 11842
Long Term Stability of FGS1r in Position Mode
It is known from our experience with FGS3, and later with
FGS1r, that an
FGS on orbit experiences long term evolution, presumably
due to
disorption of water from the instrument's graphite epoxy
composits. This
manifests principally as a change in the plate scale and
secondarily as a
change in the geometric distortions. These effects are
well modeled by
adjustments to the rhoA and kA parameters which are used
to transform
the star selector servo angles into FGS (x, y) detector
space
coordinates. By observing the relative positions of
selected stars in a
standard cluster at a fixed telescope pointing and
orientation, the
evolution of rhoA and kA can be monitored and calibrated
to preserve the
astrometric performance of FGS1r.
NIC1/NIC2/NIC3 11820
NICMOS Post-SAA Calibration - CR Persistence Part 7
Internals for CR persistence
NIC2 11548
NICMOS Imaging of Protostars in the Orion A Cloud: The
Role of
Environment in Star Formation
We propose NICMOS observations of a sample of 252
protostars identified
in the Orion A cloud with the Spitzer Space Telescope.
These
observations will image the scattered light escaping the
protostellar
envelopes, providing information on the shapes of outflow
cavities, the
inclinations of the protostars, and the overall
morphologies of the
envelopes. In addition, we ask for Spitzer time to obtain
55-95 micron
spectra of 75 of the protostars. Combining these new data
with existing
3.6 to 70 micron photometry and forthcoming 5-40 micron
spectra measured
with the Spitzer Space Telescope, we will determine the
physical
properties of the protostars such as envelope density,
luminosity,
infall rate, and outflow cavity opening angle. By
examining how these
properties vary with stellar density (i.e. clusters vs
groups vs
isolation) and the properties of the surrounding molecular
cloud; we can
directly measure how the surrounding environment
influences protostellar
evolution, and consequently, the formation of stars and
planetary
systems. Ultimately, this data will guide the development
of a theory of
protostellar evolution.
WFPC2 10884
The Dynamical Structure of Ellipticals in the Coma and
Abell 262
Clusters
We propose to obtain images of 13 relatively luminous
early type
galaxies in the Coma cluster and Abell 262 for which we
have already
collected ground based major and minor axis spectra and
images. The
higher resolution HST images will enable us to study the
central regions
of these galaxies which is crucial to our dynamical
modelling. The
complete data set will allow us to perform a full dynamical
analysis and
to derive the dark matter content and distribution, the
stellar orbital
structure, and the stellar population properties of these
objects,
probing the predictions of galaxy formation models. The
dynamical
analysis will be performed using an up-to- date
axi-symmetric orbit
superposition code.
WFPC2 11113
Binaries in the Kuiper Belt: Probes of Solar System
Formation and
Evolution
The discovery of binaries in the Kuiper Belt and related
small body
populations is powering a revolutionary step forward in
the study of
this remote region. Three quarters of the known binaries
in the Kuiper
Belt have been discovered with HST, most by our snapshot
surveys. The
statistics derived from this work are beginning to yield
surprising and
unexpected results. We have found a strong concentration
of binaries
among low-inclination Classicals, a possible size cutoff
to binaries
among the Centaurs, an apparent preference for nearly
equal mass
binaries, and a strong increase in the number of binaries
at small
separations. We propose to continue this successful
program in Cycle 16;
we expect to discover at least 13 new binary systems,
targeted to
subgroups where these discoveries can have the greatest
impact.
WFPC2 11156
Monitoring Active Atmospheres on Uranus and Neptune
We propose Snapshot observations of Uranus and Neptune to
monitor
changes in their atmospheres on time scales of weeks and
months. Uranus
equinox is only months away, in December 2007. Hubble
Space Telescope
observations during the past several years {Hammel et al.
2005, Icarus
175, 284 and references therein} have revealed strongly
wavelength-
dependent latitudinal structure, the presence of numerous
visible-wavelength cloud features in the northern
hemisphere, at least
one very long-lived discrete cloud in the southern
hemisphere, and in
2006 the first dark spot ever seen on Uranus. Long-term
ground-based
observations {Lockwood and Jerzekiewicz, 2006, Icarus 180,
442; Hammel
and Lockwood 2007, Icarus 186, 291} reveal seasonal
brightness changes
whose origins are not well understood. Recent near- IR
images of
obtained using adaptive optics on the Keck Telescope,
together with HST
observations {Sromovsky et al. 2003, Icarus 163, 256 and
references
therein} which include previous Snapshot programs {GO
8634, 10170,
10534} show a general increase in activity at south
temperate latitudes
until 2004, when
Further Snapshot observations of these two dynamic planets
will
elucidate the nature of long-term changes in their zonal
atmospheric
bands and clarify the processes of formation, evolution,
and dissipation
of discrete albedo features.
FLIGHT OPERATIONS SUMMARY:
Significant Spacecraft Anomalies: (The following are
preliminary reports
of potential non-nominal performance that will be
investigated.)
HSTARS:
11480 ACS Checksum mismatch during JV0027 installation @
254/18:00z
During installation of ACS FSW JV0027 (CS5.11
ASIC 3.1A) the checksum
mismatched during step 8 of OPS Request 18265. It
was expected that
JLSTCKSM ='abcd'x, but read back 'abcc'x.
11481 WFPC status buffer message 290 @ 254/19:27:01z
Parameter = 62012,
time = 1767, received after SMS started.
11482 WFPC status buffer message 290 @ 254/19:39:11z
Parameter = 64051,
time = 7607, received after SMS started.
11483 NCC (NICMOS CRYO-COOLER) SAFED @255/7:57:45z Status
Buffer Message
EXEC=908, Parameter=128(Octal) was received. The
action request byte
from the 8051 in operate mode had the bit set to
safe the NCC.
COMPLETED OPS REQUEST:
18262-1 NSSC-1 FSW b18.6.5 Installation @ 254/16:26z
18259-1 ESM FSW 7.0.0 Installation @ 254/18:24z
18269-0 Turn OFF WFPC-II Replacement Heater @ 254/21:03z
18267-1 CONTINGENCY NCS CPL Reservoir Setpoint Change @
254/21:06z
18270-0 Update t_min and t_setpt for NCS CPL @ 254/21:55z
18271-0 Set up NSSC Memory Monitor @ 254/22:17z
18272-0 Safe WF-2 @ 254/23:43z
18267-2 CONTINGENCY NCS CPL Reservoir Setpoint Change @
255/00:03z
18264-2 WF/PC-II RAM Dump and Compare (ROP NS-16) @
255/00:35z
18266-1 Update WFPC-II POM position in SHP after NSSC
8.6.5 FSW Installation @ 255/00:48z
18265-0 ACS JV0027 EEPROM Installation @ 255/05:52z
18260-3 NCS Recovery and Cooldown @ 255/06:53z
18273-0 Turn On NCS CPL Startup Heater 255/08:33:52z
COMPLETED OPS NOTES: None
SCHEDULED SUCCESSFUL
FGS GSacq 11 11
FGS REacq 03 03
OBAD with Maneuver 27 27
SIGNIFICANT EVENTS:
QUEEN loaded and NCS Safed
Steps 4 through 31 of Ops Request 18262 were
successfully executed
to load QUEEN and safe the NICMOS Cooling
System. The Queen FSW was
loaded and dumped. The FSW team verified the
contents. The NCC was
transitioned down and the cooling system was
safed. There were no
concerns or issues in the NCC transition or
safing. Queen was
started and operated nominally.
NSSC-1 BL 8.6.5 Loaded/Activated
Ops Request 18262 was completed at 16:26 UTC.
NSSC-1 BL 8.6.5 processing
was activated at 16:06 UTC. ESM 7.0
installation will proceed
immediately via Ops Request 18259, ~ 2? hours
AHEAD of schedule.
ESM FSW Loaded
Ops Request 18259 was successfully executed to
load and verify the ESM
8051 Flight Software, version 7.0.0. The ESM is
currently in Operate and
performing nominally. The 254 SMS was loaded
and the pointer was
set in preparation of SMS intercept. WFPC-2
Recovery will begin via
SMS at 19:20z. The CPL startup will begin
shortly, followed by the ACS
FSW load.
WFPCII SMS Recovery and NCS restart
status buffer error messages were received
while WFPC2 was being
recovered from the planned safemode following a
successful NSSC-I FSW
installation. At GMT 254/19:27:00 WFPC-II
status buffer message 290 was
reported with parameter 26510(dec). The error
indicated the temperature
of the AFM was lower than what the stored
commanding was expecting,
resulting in the AFM RTCS exiting prematurely.
The likely cause of this
error was an incorrect temperature range
utilized in the stored program
commands. At GMT 254/19:39 a second WFPC-II
status buffer message 290
with parameter 26665(dec) was reported. This
error indicated that the
WFPC-II microprocessor checksum failed during
execution of UIDLE.
Following a meeting with Project management,
WFPC-II was placed into
safe mode via OPS Request 18272 to prevent
further stored program
commanding of the instrument. ACS FSW
installation and NCS cool down are
not affected and are proceeding ahead of
schedule. The NCS compressor
was turned on at ~255:01:28. As of
255/03:12:00, the NCS was returned to
its nominal PID Operate state, beginning the
NICMOS/NCS cooldown to the
operational setpoint of 72.39 K in earnest. The
system transitioned to
the Surge state, where the Compressor maximum
speed is limited to 7043
rps. The system remained in Surge until the
Turboalternator inlet
temperature fell below the 82 K level from its
current reading of 103.4
K. At that point, full authority was granted to
the PID Control Law
to ramp the Compressor to its maximum allowed
speed of 7330 rps. With
the ramping down of the Compressor for the NCS
shutdown beginning at
roughly 254/13:16, the total down time for the
NCS during the NSSC-1 and
ESM installations was just short of 14 hours
total.
NCS Safing.
At 255/07:57:45, the NCC Safed, due to a speed
violation on the
Circulator as reported by DT 120. The CPL
continues to operate.
ACS FSW JV0027 (CS 5.11, ASIC 3.1A) Successfully Installed
ACS FSW JV0027 was successfully installed via
OR#18265 at 255/05:51 GMT.
A memory dump was performed and verified by
Payload FSW. The instrument
was transitioned to Operate Mode. No problems
were observed. ACS was
commanded to Safe mode to intercept the
recovery SMS at 255/11:00 GMT.