Notice: Due to the conversion
of some ACS WFC or HRC observations into
WFPC2, or
NICMOS observations after the loss of ACS CCD science
capability in
January, there may be an occasional discrepancy between a
proposal's listed
(and correct) instrument usage and the abstract that
follows it.
HUBBLE SPACE TELESCOPE
- Continuing to collect World Class Science
DAILY REPORT # 4440
PERIOD COVERED: UT
September 04, 2007 (DOY 247)
OBSERVATIONS SCHEDULED
WFPC2 11036
Red Leaks Closeout
We observe the star 15Mon
with 8 UV filters to check the impact of
off-band flux
{red-leak} in those filters. To derive the spectral shape
of the
red-leak, we cross each of the UV filters with F814W and F606W.
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.
WFPC2 10915
ACS Nearby Galaxy
Survey
Existing HST
observations of nearby galaxies comprise a sparse and
highly
non-uniform archive, making comprehensive comparative studies
among galaxies
essentially impossible. We propose to secure HST's
lasting impact
on the study of nearby galaxies by undertaking a
systematic,
complete, and carefully crafted imaging survey of ALL
galaxies in the
Local Universe outside the Local Group. The resulting
images will
allow unprecedented measurements of: {1} the star formation
history {SFH}
of a >100 Mpc^3 volume of the Universe with a time
resolution of
Delta[log{t}]=0.25; {2} correlations between spatially
resolved SFHs and environment; {3} the structure and properties of
thick
disks and
stellar halos; and {4} the color distributions, sizes, and
specific
frequencies of globular and disk clusters as a function of
galaxy mass
and environment. To reach these goals, we will use a
combination of
wide-field tiling and pointed deep imaging to obtain
uniform data on
all 72 galaxies within a volume-limited sample extending
to ~3.5 Mpc, with an extension to the M81 group. For each galaxy,
the
wide-field imaging
will cover out to ~1.5 times the optical radius and
will reach
photometric depths of at least 2 magnitudes below the tip of
the red
giant branch throughout the limits of the survey volume. One
additional deep
pointing per galaxy will reach SNR~10 for red clump
stars,
sufficient to recover the ancient SFH from the color-magnitude
diagram. This
proposal will produce photometric information for ~100
million stars
{comparable to the number in the SDSS survey} and uniform
multi- color
images of half a square degree of sky. The resulting
archive will
establish the fundamental optical database for nearby
galaxies, in
preparation for the shift of high- resolution imaging to
the
near-infrared.
WFPC2 11022
WFPC2 Cycle 15
Decontaminations and Associated Observations
This proposal is for
the WFPC2 decons. Also included are instrument
monitors tied to
decons: photometric stability check, focus monitor,
pre- and
post-decon internals {bias, intflats,
kspots, & darks}, UV
throughput check,
VISFLAT sweep, and internal UV flat check.
WFPC2 11038
Narrow Band and Ramp
Filter Closeout
These observations are
to improve calibration of narrow band and ramp
filters. We
also test for changes in the filter properties during
WFPC2's 14 years
on-board HST.
WFPC2 11201
Systemic and Internal
motions of the Magellanic Clouds: Third Epoch
Images
In Cycles 11 and 13 we
obtained two epochs of ACS/HRC data for fields in
the Magellanic Clouds centered on background quasars. We used
these data
to
determine the proper motions of the LMC and SMC to better than 5% and
15% respectively. These
are by far the best determinations of the proper
motions of
these two galaxies. The results have a number of unexpected
implications for the
Milky Way-LMC-SMC system. The implied
three-dimensional velocities
are larger than previously believed, and
are not
much less than the escape velocity in a standard 10^12 solar
mass Milky
Way dark halo. Orbit calculations suggest the Clouds may not
be bound
to the Milky Way or may just be on their first passage, both of
which would
be unexpected in view of traditional interpretations of the
Magellanic Stream.
Alternatively, the Milky Way dark halo may be a
factor of two
more massive than previously believed, which would be
surprising in view
of other observational constraints. Also, the
relative
velocity between the LMC and SMC is larger than expected,
leaving open
the possibility that the Clouds may not be bound to each
other. To
further verify and refine our results we now request an epoch
of
WFPC2/PC data for the fields centered on 40 quasars that have at
least one
epoch of ACS imaging. We request execution in snapshot mode,
as in our
previous programs, to ensure the most efficient use of HST
resources. A
third epoch of data of these fields will provide crucial
information to
verify that there are no residual systematic effects in
our
previous measurements. More importantly, it will increase the time
baseline from 2
to 5 yrs and will increase the number of fields with at
least two
epochs of data. This will reduce our uncertainties
correspondingly, so
that we can better address whether the Clouds are
indeed bound
to each other and to the Milky Way. It will also allow us
to
constrain the internal motions of various populations within the
Clouds, and will allow
us to determine a distance to the LMC using
rotational
parallax.
WFPC2 11312
The Local Cluster
Substructure Survey {LoCuSS}: Deep Strong Lensing
Observations with
WFPC2
LoCuSS is a
systematic and detailed investigation of the mass,
substructure, and thermodynamics
of 100 X-ray luminous galaxy clusters
at
0.15<z<0.3. The primary goal is to test our recent suggestion that
this
population is dominated by dynamically immature disturbed clusters,
and that
the observed mass-temperature relation suffers strong
structural
segregation. If confirmed, this would represent a paradigm
shift in our
observational understanding of clusters, that were hitherto
believed to be
dominated by mature, undisturbed systems. We propose to
complete our
successful Cycle 15 program {SNAP:10881} which prior to
premature
termination had delivered robust weak-lensing
detections in 17
clusters, and
candidate strongly-lensed arcs in 11 of these 17.
These
strong and
weak lensing signals will give an accurate measure of
the
total mass
and structure of the dark matter distribution that we will
subsequently compare
with X-ray and Sunyaev Zeldovich
Effect
observables. The
broader applications of our project include 1} the
calibration of
mass-temperature and mass-SZE scaling relations which
will be
critical for the calibration of proposed dark energy
experiments, and 2}
the low redshift baseline study of the demographics
of massive
clusters to aid interpretation of future high redshift
{z>1}
cluster
samples. To complete the all-important high resolution imaging
component of our
survey, we request deep WFPC2 observations of 20
clusters through
the F606W filter, for which wide-field weak-lensing
data are
already available from our Subaru imaging program. The
combination of deep
WFPC2 and Subaru data for these 20 clusters will
enable us to
achieve the science program approved by the Cycle 15 TAC.
FLIGHT OPERATIONS
SUMMARY:
Significant Spacecraft
Anomalies: (The following are preliminary reports
of potential
non-nominal performance that will be investigated.)
HSTARS:
10983 Loss of Lock -
Without Acquisition Failure @ 247/2041z
GSAcq (1,2,1) at 247/19:45z was successful. At 247/20:13:57z began
flagging in and
out of Gyro Control (RGA Only / FGS/RGA). Additionally,
Mnemonics FSUBLOL, FGSLOL, FGS_STAT
began flagging in and out indicating
a possible Loss
of Lock. At 247/20:41:56z TERM EXP as scheduled. During
this time FGS's maintained SCI INIT / LATCH on acquisition.
COMPLETED OPS REQUEST:
18142-0 Another LBBIAS
after long M2G interval @ 247/1038z
18140-1 Recover NICMOS
from Safe to SAA Oper @ 247/1704z
18143-0 Enable NICMOS
Buffer
COMPLETED OPS NOTES:
(None)
SCHEDULED SUCCESSFUL Failure
FGS GSacq
9 9
FGS REacq
5 5
OBAD with
Maneuver 28 28
Loss of Lock
(LOL) 1
SIGNIFICANT EVENTS:
NICMOS Recovery to SAA
Operate Flash Report
As of 247/17:04:35 UTC, NICMOS was
brought up to its' SAA Operate state.
As expected, the Buffer Box 2
temperature remained below -12 degC (at
-12.12 degC), so
the Buffer Box commanding was skipped in the SAA
transition. At
247/17:09:22 UTC, Buffer
an effort to
warm Buffer Box 2. Once the temperature is above -12 degC,
Buffer
will be briefly
transitioned from SAA Operate to Operate and back again
to refresh the
telemetry collection on all three Buffer Boxes.
-
____________________________________________________________
Lynn F. Bassford
Hubble Space Telescope
CHAMP
CHAMP Flight Operations Team Manager
Lockheed Martin
NASA GSFC PH#: 301-286-2876
"The Hubble Space Telescope is the
astronomical observatory and key to unlocking the most cosmic mysteries of the
past, present and future." - 7/26/6