HUBBLE SPACE TELESCOPE - Continuing to collect World Class
Science
DAILY REPORT #4686
PERIOD COVERED: 5am August 29 - 5am September 2, 2008 (DOY
242/0900z-246/0900z)
OBSERVATIONS SCHEDULED
NIC1/NIC2/NIC3 11820
NICMOS Post-SAA Calibration - CR Persistence Part 7
Internals for CR persistence
WFPC2 11797
Supplemental WFPC2 CYCLE 16 Intflat Linearity Check and
Filter Rotation
Anomaly Monitor
Supplemental observations to 11029, to cover period from
Aug 08 to SM4.
Intflat observations will be taken to provide a linearity
check: the
linearity test consists of a series of intflats in F555W,
in each gain
and each shutter. A combination of intflats, visflats, and
earthflats
will be used to check the repeatability of filter wheel
motions.
(Intflat sequences tied to decons, visits 1-18 in prop
10363, have been
moved to the cycle 15 decon proposal 11022 for easier
scheduling.)
Note: long-exposure WFPC2 intflats must be scheduled
during ACS anneals
to prevent stray light from the WFPC2 lamps from
contaminating long ACS
external exposures.
Note: These are supplemental observations to cover June to
SM4 (oct 8
'08) + 6 months.
WFPC2 11795
WFPC2 Cycle 16 UV Earth Flats
Monitor flat field stability. This proposal obtains
sequences of earth
streak flats to improve the quality of pipeline flat
fields for the
WFPC2 UV filter set. These Earth flats will complement the
UV earth flat
data obtained during cycles 8-15.
WFPC2 11794
Cycle 16 Visible Earth Flats
This proposal monitors flatfield stability. This proposal
obtains
sequences of Earth streak flats to construct high quality
flat fields
for the WFPC2 filter set. These flat fields will allow
mapping of the
OTA illumination pattern and will be used in conjunction
with previous
internal and external flats to generate new pipeline
superflats. These
Earth flats will complement the Earth flat data obtained
during cycles
4-15.
WFPC2 11793
WFPC2 Cycle 16 Internal Monitor
This calibration proposal is the Cycle 15 routine internal
monitor for
WFPC2, to be run weekly to monitor the health of the
cameras. A variety
of internal exposures are obtained in order to provide a
monitor of the
integrity of the CCD camera electronics in both bays (both
gain 7 and
gain 15 -- to test stability of gains and bias levels), a
test for
quantum efficiency in the CCDs, and a monitor for possible
buildup of
contaminants on the CCD windows. These also provide raw
data for
generating annual super-bias reference files for the
calibration
pipeline.
WFPC2 11553
HST Imaging of the Luminous Transient in NGC 300
A luminous optical transient discovered in the nearby
(~2.2 Mpc)
Sculptor Group spiral NGC 300 in May 2008 appears to be a
new member of
the V838 Monocerotis class of stars that expand in a few
weeks to become
red supergiants. Spectroscopic observations show that the
NGC 300 OT is
categorically not a classical nova, supernova, or luminous
blue
variable. At an absolute magnitude of -12.5, it is by far
the brightest
star at present in NGC 300, but if it follows the pattern
of V838 Mon
and the similar object M31 RV, it will fade away rapidly
in about 3
months.
Before it fades, we propose to obtain WFPC2 images in
order to locate
the position of the object to within a few milliarcsec.
This will allow
us to identify the progenitor object, based on a superb
set of
pre-outburst ACS and WFPC2 images of NGC 300 available in
the archive.
We also propose a second observation in September 2008, in
order to
search for emergence of a light echo similar to the
spectacular one that
surrounds V838 Mon. If a light echo does appear, follow-up
ACS
polarimetry after SM4 offers the possibility of a direct
geometric
distance determination, allowing a fundamental calibration
of the rich
variety of standard candles that exist in NGC 300
(Cepheids, red-giant
tip, planetary nebulae, etc.).
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.
NIC2 11547
Characterizing Pre-Main Sequence Populations in Stellar
Associations of
the Large Magellanic Cloud
The Large Magellanic Cloud (LMC) offers an extremely rich
sample of
resolved low-mass stars (below 1 Solar Mass) in the act of
formation
that has not been explored sufficiently yet. These
pre-main sequence
(PMS) stars provide a unique snapshot of the star
formation process, as
it is being recorded for the last ~20 Myr, and they give
important
information on the low-mass Initial Mass Function (IMF) of
their host
stellar systems. Studies of young, rich LMC clusters like
30 Doradus are
crowding limited, even at the angular resolution
facilitated by HST in
the optical. To learn more about low-mass PMS stars in the
LMC, one has
to study less crowded regions like young stellar
associations. We
propose to employ WFPC2 to obtain deep photometry (V ~
25.5 mag) of four
selected LMC stellar associations in order to perform an
original
optical analysis of their red PMS and blue bright MS
stellar
populations. With these observations we aim at a
comprehensive study,
which will add substantial information on the most recent
star formation
and the IMF in the LMC. The data reduction and analysis
will be
performed with a 2D photometry software package especially
developed by
us for WFPC2 imaging of extended stellar associations with
variable
background. Our targets have been selected optimizing a
combination of
criteria, namely spatial resolution, crowding, low
extinction, nebular
contamination, and background confusion in comparison to
other regions
in the Local Group. Parallel NICMOS imaging will provide
additional
information on near-infrared properties of the stellar
population in the
regions surrounding these systems.
WFPC2 11544
The Dynamical Legacy of Star Formation
We propose to use WFPC2 to conduct a wide-field imaging
survey of the
young cluster IC348. This program, in combination with
archival HST
observations, will allow us to measure precise proper
motions for
individual cluster members, characterizing the
intra-cluster velocity
dispersion and directly studying the dynamical signatures
of star
formation and early cluster evolution. Our projected
astrometric
precision (~1 mas in each epoch) will allow us to
calculate individual
stellar velocities to unprecedented precision (<0.5
mas/yr; <1 km/s) and
directly relate these velocities to observed spatial
substructure within
the cluster. This survey will also allow us to probe
small-scale star
formation physics by searching for high-velocity stars
ejected from
decaying multiple systems, expanding our knowledge of
multiplicity in
dense environments, and identifying new substellar and planetary-mass
cluster members based on kinematic membership tests.
WFPC2 11302
WFPC2 CYCLE 16 Standard Darks - Part III
This dark calibration program obtains dark frames every
week in order to
provide data for the ongoing calibration of the CCD dark
current rate,
and to monitor and characterize the evolution of hot
pixels. Over an
extended period these data will also provide a monitor of
radiation
damage to the CCDs.
NIC2 11237
The Origin of the Break in the AGN Luminosity Function
We propose to use NICMOS imaging to measure rest-frame
optical
luminosities and morphological properties of a complete
sample of faint
AGN host galaxies at redshifts z ~ 1.4. The targets are
drawn from the
VLT-VIMOS Deep Survey, and they constitute a sample of the
lowest
luminosity type 1 AGN known at z > 1. The
spectroscopically estimated
black hole masses are up to an order of magnitude higher
than expected
given their nuclear luminosities, implying highly
sub-Eddington
accretion rates. This exactly matches the prediction made
by recent
theoretical models of AGN evolution, according to which
the faint end of
the AGN luminosity function is populated mainly by big
black holes that
have already exhausted a good part of their fuel. In this
proposal we
want to test further predictions of that hypothesis, by
focusing on the
host galaxy properties of our low-luminosity, low-
accretion AGN. If the
local ratio between black hole and bulge masses holds at
least
approximately at these redshifts, one expects most of
these
low-luminosity AGN to reside in fairly big ellipticals
with stellar
masses around and above 10^11 solar masses (in contrast to
the Seyfert
phenomenon in the local universe). With NICMOS imaging we
will find out
whether that is true, implying also a sensitive test for
the validity of
the M_BH/M_bulge relation at z ~ 1.4.
WFPC2 11235
HST NICMOS Survey of the Nuclear Regions of Luminous
Infrared Galaxies
in the Local Universe
At luminosities above 10^11.4 L_sun, the space density of
far-infrared
selected galaxies exceeds that of optically selected
galaxies. These
`luminous infrared galaxies' {LIRGs} are primarily
interacting or
merging disk galaxies undergoing enhanced star formation
and Active
Galactic Nuclei {AGN} activity, possibly triggered as the
objects
transform into massive S0 and elliptical merger remnants.
We propose
NICMOS NIC2 imaging of the nuclear regions of a complete
sample of 88
L_IR > 10^11.4 L_sun luminous infrared galaxies in the
IRAS Revised
Bright Galaxy Sample {RBGS: i.e., 60 micron flux density
> 5.24 Jy}.
This sample is ideal not only in its completeness and
sample size, but
also in the proximity and brightness of the galaxies. The
superb
sensitivity and resolution of NICMOS NIC2 on HST enables a
unique
opportunity to study the detailed structure of the nuclear
regions,
where dust obscuration may mask star clusters, AGN and
additional nuclei
from optical view, with a resolution significantly higher
than possible
with Spitzer IRAC. This survey thus provides a crucial
component to our
study of the dynamics and evolution of IR galaxies
presently underway
with Wide-Field, HST ACS/WFC and Spitzer IRAC observations
of these 88
galaxies. Imaging will be done with the F160W filter
{H-band} to examine
as a function of both luminosity and merger stage {i} the
luminosity and
distribution of embedded star clusters, {ii} the presence
of optically
obscured AGN and nuclei, {iii} the correlation between the
distribution
of 1.6 micron emission and the mid-IR emission as detected
by Spitzer
IRAC, {iv} the evidence of bars or bridges that may funnel
fuel into the
nuclear region, and {v} the ages of star clusters for
which photometry
is available via ACS/WFC observations. The NICMOS data,
combined with
the HST ACS, Spitzer, and GALEX observations of this
sample, will result
in the most comprehensive study of merging and interacting
galaxies to
date.
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.
NIC1 11205
The Effects of Multiplicity on the Evolution of Young
Stellar Objects: A
NICMOS Imaging Study
We propose to use NICMOS to investigate the multiplicity
of young
stellar objects (YSOs) in the Orion B molecular cloud.
Previous
observations with the Spitzer Space Telescope have
revealed a remarkable
star forming filament near the NGC 2068 reflection nebula.
The
population of YSOs associated with the filament exhibit a
surprisingly
wide range of circumstellar evolutionary states, from
deeply embedded
protostars to T Tauri accretion disks. Many of the
circumstellar disks
themselves show evidence for significant dust evolution,
including grain
growth and settling and cleared inner holes, apparently in
spite of the
very young age of these stars. We will estimate the binary
fraction of a
representative sample of objects in these various stages
of evolution in
order to test whether companions may play a significant
role in that
evolution.
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.
WEPC2 11196
An Ultraviolet Survey of Luminous Infrared Galaxies in the
Local
Universe
At luminosities above 10^11.4 L_sun, the space density of
far-infrared
selected galaxies exceeds that of optically selected
galaxies. These
Luminous Infrared Galaxies {LIRGs} are primarily
interacting or merging
disk galaxies undergoing starbursts and creating/fueling
central AGN. We
propose far {ACS/SBC/F140LP} and near {WFPC2/PC/F218W} UV
imaging of a
sample of 27 galaxies drawn from the complete IRAS Revised
Bright Galaxy
Sample {RBGS} LIRGs sample and known, from our Cycle 14 B
and I-band ACS
imaging observations, to have significant numbers of
bright {23 < B < 21
mag} star clusters in the central 30 arcsec. The HST UV
data will be
combined with previously obtained HST, Spitzer, and GALEX
images to {i}
calculate the ages of the clusters as function of merger
stage, {ii}
measure the amount of UV light in massive star clusters
relative to
diffuse regions of star formation, {iii} assess the
feasibility of using
the UV slope to predict the far-IR luminosity {and thus
the star
formation rate} both among and within IR-luminous
galaxies, and {iv}
provide a much needed catalog of rest- frame UV
morphologies for
comparison with rest-frame UV images of high-z LIRGs and
Lyman Break
Galaxies. These observations will achieve the resolution
required to
perform both detailed photometry of compact structures and
spatial
correlations between UV and redder wavelengths for a physical
interpretation our IRX-Beta results. The HST UV data,
combined with the
HST ACS, Spitzer, Chandra, and GALEX observations of this
sample, will
result in the most comprehensive study of luminous
starburst galaxies to
date.
WFPC2 11167
A Unique High Resolution Window to Two Strongly Lensed
Lyman Break
Galaxies
On rare occasions, the otherwise very faint Lyman Break
Galaxies {LBGs}
are magnified by gravitational lensing to provide
exceptional targets
for detailed spectroscopic and imaging studies. We propose
HST WFPC2 and
NICMOS imaging of two strongly lensed Lyman Break Galaxies
{LBGs} that
were recently discovered by members of our team. These two
LBGs -- the
"8 O'Clock Arc" and the "SDSS J1206+5142
Arc" -- are currently the
brightest known LBGs, roughly 3 times brighter than the
former
record-holder, MS1512-cB58 {a.k.a. "cB58"}. The
z=2.73 "8 O'Clock Arc"
extends ~10 arcsec in length and is magnified by a factor
of 12. The
z=2.00 "SDSS J1206+5142 Arc" also extends ~10
arcsec in length and is
magnified by a factor of 30. Due to their brightness and
magnification,
these two strongly lensed LBGs offer an unprecedented
opportunity for
the very detailed investigation of two individual galaxies
at high
redshift. We are currently pursuing a vigorous
ground-based campaign to
obtain multi- wavelength {UV, optical, NIR, radio}
observations of these
two LBGs, but our campaign currently lacks a means of
obtaining
high-resolution optical/NIR imaging -- a lack that
currently only HST
can address. Our prime objective for this proposal is to
obtain high
resolution HST images of these two systems with two-orbit
WFPC2 images
in the BVI bands and two-orbit NICMOS/NIC2 images in the J
and H bands.
These data will allow us to construct detailed lensing
models, probe the
mass and light profiles of the lenses and their
environments, and
constrain the star formation histories and rest-frame
UV/optical
spectral energy distributions of the LBGs.
ACS/SBC 11158
HST Imaging of UV Emission in Quiescent Early-type
Galaxies
We have constructed a sample of early type galaxies at
z~0.1 that have
blue UV-optical colors, yet also show no signs of optical
emission, or
extended blue light. We have cross-correlated the SDSS
catalog and the
Galaxy Evolution Explorer Medium Imaging Survey to select
a sample of
galaxies where this UV emission is strongest. The origin
of the UV
rising flux in these galaxies continues to be debated, and
the
possibility that some fraction of these galaxies may be
experiencing low
levels of star formation cannot be excluded. There is also
a possibility
that low level AGN activity {as evidenced by a point
source} is
responsible We propose to image the UV emission using the
HST/SBC and to
explore the morphology of the UV emission relative to the
optical light.
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.
NIC2 11150
Beta Pic Polarimetry with NICMOS
Debris disk stars host transient dust grains that comprise
a collisional
cascade with sizes ranging from planetesimals to the
sub-micron. In
addition to the gravity of the host star and any planets
present, these
grains are subject to size-dependent non-gravitational
forces, e.g.,
corpuscular drag and radiation pressure. When a steep
spectrum of grain
sizes prevails, such as the Dohnanyi distribution,
scattered light
images preferentially trace grains with dimensionless size
parameter of
order unity. Thus images in scattered starlight provide
unique windows
on the balance of forces acting on grains at a specific
size. Therefore,
in an A star system such as beta Pic, the near-IR is
dominated by grains
close to the blow out size and therefore NICMOS traces
dust on
hyperbolic orbits.
Scattering is fundamentally polarization sensitive, and
measurements
that record intensity literally see only half the picture.
If linear
polarization is measured then the elements of the complex
scattering
matrix can be reconstructed. These matrix elements provide
fundamental
constraints on the size, composition and structure of the
scatterers.
Notably, polarimetry can be used to break the degeneracy
between
scattering asymmetry, g, and the radial dust gradient,
which are
otherwise covariant in an edge-on disk. Thus, we can use
polarimetry to
localize the parent bodies in the beta Pic disk.
In beta Pic, dust is thought to originate mainly from the
sublimation of
cometary bodies near periastron. The irradiation of
cometary material
leads to sublimation and photodissociation of ices forming
porous grains
consisting of a matrix of refractory material. Such grains
have a
characteristic scattering signature in polarized light that
can be
distinguished from compact grains that arise from
collisional erosion of
asteroidal material.
WFPC2 11134
WFPC2 Tidal Tail Survey: Probing Star Cluster Formation on
the Edge
The spectacular HST images of the interiors of merging
galaxies such as
the Antennae and NGC 7252 have revealed rich and diverse
populations of
star clusters created over the course of the interaction.
Intriguingly,
our WFPC2 study of tidal tails in these and other
interacting pairs has
shown that star cluster birth in the tails does not follow
a similarly
straightforward evolution. In fact, cluster formation in
these
relatively sparse environments is not guaranteed -- only
one of six
tails in our initial study showed evidence for a
significant population
of young star clusters. The tail environment thus offers
the opportunity
to probe star cluster formation on the edge of the
physical parameter
space {e.g., of stellar and gas mass, density, and
pressure} that
permits it to occur. We propose to significantly extend
our pilot sample
of optically bright, gas-rich tidal tails by a factor of 4
in number to
include a more diverse population of tails, encompassing
major and minor
mergers, gas-rich and gas-poor tails, as well as early,
late, and merged
interaction stages. With 21 orbits of HST WFPC2 imaging in
the F606W and
F814W filters, we can identify, roughly age-date, and
measure sizes of
star clusters to determine what physical parameters affect
star cluster
formation. WFPC2 imaging has been used effectively in our
initial study
of four mergers, and it will be possible in this program
to reach
similar limits of Mv=-8.5 for each of 16 more tails. With
the much
larger sample we expect to isolate which factors, such as
merger stage,
HI content, and merger mass ratio, drive the formation of
star clusters.
WFPC2 11130
AGNs with Intermediate-mass Black Holes: Testing the Black
Hole-Bulge
Paradigm, Part II
The recent progress in the study of central black holes in
galactic
nuclei has led to a general consensus that supermassive {10^6-10^9
solar
mass} black holes are closely connected with the formation
and
evolutionary history of large galaxies, especially their
bulge
component. Two outstanding issues, however, remain
unresolved. Can
central black holes form in the absence of a bulge? And
does the mass
function of central black holes extend below 10^6 solar
masses?
Intermediate-mass black holes {<10^6 solar masses}, if
they exist, may
offer important clues to the nature of the seeds of
supermassive black
holes. Using the SDSS, our group has successfully
uncovered a new
population of AGNs with intermediate-mass black holes that
reside in
low-luminosity galaxies. However, very little is known
about the
detailed morphologies or structural parameters of the host
galaxies
themselves, including the crucial question of whether they
have bulges
or not. Surprisingly, the majority of the targets of our
Cycle 14 pilot
program have structural properties similar to dwarf
elliptical galaxies.
The statistics from this initial study, however, are
really too sparse
to reach definitive conclusions on this important new
class of black
holes. We wish to extend this study to a larger sample, by
using the
Snapshot mode to obtain WFPC2 F814W images from a parent
sample of 175
AGNs with intermediate- mass black holes selected from our
final SDSS
search. We are particularly keen to determine whether the
hosts contain
bulges, and if so, how the fundamental plane properties of
the host
depend on the mass of their central black holes. We will
also
investigate the environment of this unique class of AGNs.
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.
FLIGHT OPERATIONS SUMMARY:
Significant Spacecraft Anomalies: (The following are
preliminary reports
of potential non-nominal performance that will be
investigated.)
HSTARS:
11461 - GSAcq (1,2,2) and REAcq failed to RGA Hold due to
QSTOP flag on FGS1
GSAcq (1,2,2), scheduled from 243/14:08:05 - 14:15:22z. REAcq
(1,2,2),
scheduled from 15:43:17 - 15:50:34z. Observations affected:
WFPC2 #189-194,
Proposals #11167 & 11795.
11463 - GSAcq(1,2,2) and 3 REAcqs failed to gyro control
with QSTOP flag oon FGS1
REACQ(1,2,2) at 07:41:26z, 09:17:19 & 10:54:01z.
Observations affected: WFPC 199-218, Proposals #11167 &
11795.
COMPLETED OPS REQUEST: (None)
COMPLETED OPS NOTES: (None)
SCHEDULED
SUCCESSFUL
FGS GSacq
38
36
FGS
REacq
16
12
OBAD with Maneuver
108
108
SIGNIFICANT EVENTS: (None)