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Daily 3442



HUBBLE SPACE TELESCOPE

DAILY REPORT       # 3442

PERIOD COVERED: DOYs 248-250

OBSERVATIONS SCHEDULED

NIC3 9998

NICMOS Cycle 12 Grism Calibration and Standard Stars to 2.5microns

This is the grism calibration proposal.

ACS 9984

Cosmic Shear With ACS Pure Parallels

Small distortions in the shapes of background galaxies by foreground
mass provide a powerful method of directly measuring the amount and
distribution of dark matter. Several groups have recently detected
this weak lensing by large-scale structure, also called cosmic shear.
The high resolution and sensitivity of HST/ACS provide a unique
opportunity to measure cosmic shear accurately on small scales. Using
260 parallel orbits in Sloan textiti {F775W} we will measure for the
first time: beginlistosetlength sep0cm setlengthemsep0cm setlength
opsep0cm em the cosmic shear variance on scales <0.7 arcmin, em the
skewness of the shear distribution, and em the magnification effect.
endlist Our measurements will determine the amplitude of the mass
power spectrum sigma_8Omega_m^0.5, with signal-to-noise {s/n} ~ 20,
and the mass density Omega_m with s/n=4. They will be done at small
angular scales where non-linear effects dominate the power spectrum,
providing a test of the gravitational instability paradigm for
structure formation. Measurements on these scales are not possible
from the ground, because of the systematic effects induced by PSF
smearing from seeing. Having many independent lines of sight reduces
the uncertainty due to cosmic variance, making parallel observations
ideal.

NIC2 9875

The Fundamental Plane of Massive Gas-Rich Mergers

We propose deep NICMOS H-band imaging of a carefully selected sample
of 33 luminous, late-stage galactic mergers. This program is part of a
comprehensive investigation of the most luminous mergers in the nearby
universe, the ultraluminous infrared galaxies {ULIGs}. The
high-resolution HST images will complement an extensive set of
ground-based data that include long-slit NIR spectra from a recently
approved Large VLT Programme. This unique dataset will allow us to
derive with unprecedented precision structural -and- kinematic
parameters for a large unbiased sample of objects spanning the entire
ULIG luminosity function. These data will refine the fundamental plane
of massive gas-rich mergers and enable us to answer the following
questions: {1} Do ultraluminous mergers form elliptical galaxies, and
in particular, giant ellipticals? {2} Do ULIGs evolve into optically
bright QSOs? The results from this detailed study of massive mergers
in the local universe will be relevant to understanding galaxy
formation and evolution at earlier epochs, and in particular, the
dusty sub-mm population that accounts for more than half of the star
formation at z > 1.

ACS/HRC 9853

A Search for Young Binary Brown Dwarfs: Constraining Formation
Scenarios and Masses Through Multiplicity

We propose to use the Advanced Camera for Surveys / High Resolution
Camera to conduct a direct imaging multiplicity survey of 34 young
brown dwarfs in the nearest regions of recent star formation, the T
association Taurus-Auriga and the OB association Upper Scorpius. The
determined multiplicity fraction, the separation distribution, and the
mass ratio distribution will offer stringent observational constraints
on proposed brown dwarf formation scenarios. Moreover, the small
semi-major axes of known field and open cluster brown dwarf binaries
suggest the exciting possibility of our identifying several very close
binaries {< 15 AU}. Continued monitoring of these systems would yield,
on a decade timescale, the first dynamical mass estimates of T Tauri
brown dwarfs. With masses intermediate between those of stars and
planets, brown dwarfs offer our best hope of relating the reasonably
well understood processes of star formation to the less well
understood processes of planet formation.

NIC1 9843

NICMOS Observations of Cool Brown Dwarf Doubles

We propose to use NICMOS to observe two brown dwarf systems discovered
using HST/WFPC2 imaging. Each of the two late-L dwarf primaries has a
secondary that is much fainter. Based on the limited optical
photometry available, the secondaries lie at the L/T Dwarf transition,
and may lie anywhere in the range from L9 {cooler than any known L
dwarf} or early-T. NICMOS photometry will be used to characterize the
spectral energy distribution and search for methane absorption.

ACS/WFC 9842

A Snapshot Search for Halo Very-Low-Mass Binaries

We propose a snapshot search for binary M subdwarf stars. These nearby
stars have high velocities and low metallicies that identify them as
members of the old Galactic halo {Population II}. ACS imaging is
requested to search for secondary companions. This supplements a
previous snapshot program that only obtained 10 observations. The
observed binary fraction will be compared to the disk M dwarf fraction
to look for differences in star formation. It is likely that a system
suitable for orbital mass determinations will be found. In this case,
future HST observations could determine the first masses for
very-low-mass, low-metallicity stars.

NIC2 9834

Finding Planets in the Stellar Graveyard: A Faint Companion Search of
White Dwarfs with NICMOS

We propose to do a deep search for substellar objects in orbit around
white dwarfs with the newly refurbished NICMOS camera as part of the
PI's doctoral thesis work. Direct imaging of planets around main
sequence stars is difficult due to the large contrast ratio, a problem
which is much less severe for companions to white dwarfs. White dwarfs
are not usually considered in planet searches but recent theoretical
work and observations are motivating new searches for planetary
systems and dust disks around DAZ white dwarfs. We propose to conduct
the search with the NIC2 coronagraph to find resolved companions and
do photometry to search for unresolved companions through Near-IR
excesses. We estimate that the survey will be sensitive to brown
dwarfs, high mass jovian planets, and dust disks. By probing a wide
range of orbital separations and companion masses, this survey will
help to answer questions about the brown dwarf desert, common envelope
evolution, and planet formation. HST and NICMOS provide a unique
capability to do this search, as no ground based observatory with AO
can adequately search for faint companions as close and with such high
contrast.

NIC1 9833

T Dwarf Companions: Searching for the Coldest Brown Dwarfs

Faint companions to known stars have historically led to the discovery
of new classes of stellar and substellar objects. Because these
discoveries are typically limited by the flux ratio of the components
in the system, the intrinsically faintest companions are most
effectively identified around the intrinsically faintest primaries. We
propose to use NICMOS to image a sample of 22 of the coolest known
{T-type} brown dwarfs in the Solar Neighborhood in order to search for
fainter and cooler brown dwarf companions. The high spatial resolution
of the NIC 1 detector enables us to distinguish binary systems with
apparent separations greater than 0"08, or physical separations
greater than 1.2 AU at the nominal distances of the objects in our
sample. Furthermore, the substantial sensitivity of NICMOS imaging
allows us to probe companion masses of 5-50 Jupiter masses and
companion effective temperatures of 250-1300 K in a maximally
efficient manner. Based on work to date, we expect that roughly 20% of
the objects in our sample will be binary, and that one or two of these
will likely harbor a significantly fainter secondary. Hence, we expect
to find a companion cooler than any currently known brown dwarf, a
potential prototype for the next spectral class. In addition, our
investigation will add substantially to the sample of known binary
brown dwarfs, allowing improved statistical analyses of the binary
fraction, separation distribution, and mass ratio distribution of
these systems, key quantities for probing brown dwarf formation. We
will also identify optimal substellar systems for astrometric mass
measurements, a critical check for theoretical models of brown dwarfs
and extrasolar planets.

NIC3/ACS/HRC/WFC 9803

Deep NICMOS Images of the UDF

The ACS Ultra Deep Field {UDF} images will greatly enhance the rich
suite of deep multi-wavelength images in the Chandra Deep Field South
{CDF--S}. We propose to complete the image set with deep near-IR
NICMOS images at 1.1 and 1.6 microns over a significant fraction of
the UDF, providing a critical link between the HST ACS and SIRTF
observations. The timely addition of the near-IR images ensures that
investigators will have images that span the spectrum from X-ray to
far IR. In recognition of the value of the near IR images this
proposal is submitted as a Treasury proposal with no proprietary
period. The proposal team will deliver science quality images,
mosaiced images covering 4.9 sq arc min, and a photometric catalog
complete to an AB mag of 28.2 in both the F110W and F160W filters. The
program also delivers a parallel extremely deep ACS field, 8' away,
that reaches to within 0.6 mag of the UDF in the same filters as the
UDF. The scientific program of the proposal team focuses on the star
formation history of the universe, evolved galaxies at high redshift,
galaxies at the epoch of reionization, and the redshift evolution of
AGNs and ULIRGs. The HDF-N is currently the only field with
spatially-coincident deep HST imaging in both the optical and near-IR.
The small size of the HDF-N means that large scale structure is the
dominant error in the results from the HDF-N. Providing observations
in a field that is spatially uncorrelated is critically important. The
UDF/CDF-S fulfills that goal. The depth of the UDF ACS imaging, and
the wealth of Great Observatory and ground based observations in the
CDF-S, make these NICMOS observations uniquely valuable. An
extraordinarily rich array of science opportunities await the
community from the NICMOS UDF data.

NIC2 9801

Are OH/IR Stars the Youngest post-AGB stars? A NICMOS Imaging Survey

Essentially all well-characterized preplanetary nebulae {PPNe}--
objects in transition between the AGB and planetary nebula
evolutionary phases - are bipolar, whereas the mass-loss envelopes of
AGB stars are strikingly spherical. In order to understand the
processes leading to bipolar mass-ejection, we need to know at what
stage of stellar evolution does bipolarity in the mass-loss first
manifest itself. We have recently hypothesized that most OH/IR stars
{evolved mass- losing stars with OH maser emission} are very young
PPNe. We are conducting a multiwavelength survey program of imaging
and spectroscopic observations of such objects, using a large,
morphologically unbiased sample selected using IRAS 12-to-25 micron
colors. Our ongoing HST/SNAP imaging survey of the optically bright
half of this sample with WFPC2 and ACS is highly successful: 19/32
objects observed are extended with bipolar/multipolar shapes
{remaining objects are unresolved}. Slightly more than 50% of our
sample are optically too faint or undetected but have strong near-IR
counterparts -- we therefore propose a NICMOS SNAPshot imaging survey
of these optically-faint OH/IR stars. These observations are crucial
for determining how and when the bipolar geometry asserts itself. The
results from our NICMOS survey {together with the WFPC2/ACS survey}
will allow us to draw general conclusions about the onset of bipolar
mass-ejection during late stellar evolution. Our complementary program
of interferometric mapping of the OH maser emission in our sources is
yielding kinematic information with spatial resolution comparable to
that in the HST images. The HST/radio data will provide crucial input
for theories of post-AGB stellar evolution. In addition, these data
will also indicate whether the multiple concentric rings, "searchlight
beams'', and truncated equatorial disks recently discovered with HST
in a few PPNe, are common or rare phenomena.

ACS/HRC/WFC 9763

Calibrating the Black Hole Mass Scale for Quasars

We propose to obtain ACS/WFC imaging of all 17 low-redshift quasars
that have black hole masses measured from reverberation mapping. This
is a key sample since all secondary methods to estimate black hole
mass in quasars depend on this local reverberation-mapped sample for
their calibration. The best external check on reverberation mapping is
whether it gives results that are consistent with the black hole mass-
host galaxy correlations of nearby galaxies. For local Seyfert
galaxies the reverberation masses appear consistent with the M-sigma
correlation, but it is not known whether this also holds true for
quasars because the stellar velocity dispersions of quasar hosts are
virtually impossible to measure. We will use the ACS data to measure
accurate bulge parameters {luminosity and effective radius} for the
host galaxies of the reverberation-mapped quasars. From the
fundamental plane or the Faber-Jackson relation, we can estimate the
host galaxy velocity dispersion and test whether the reverberation
masses follow the M-sigma relation even for objects with quasar
luminosities. This is a crucial test if we are to trust the
reverberation masses as the lowest rung on a "distance ladder" of
black hole mass estimators for quasars, so that quasars can be used to
trace the cosmological growth history of black holes. {Note added in
Phase II: the TAC awarded us 8 orbits to observe 7 quasars and a PSF
star.}

WFPC2/ACS/WFC 9761

A morphological study of EROs and sub-mm sources in a unique deep field

We propose a deep I-band ACS WFC survey in a unique deep field,
focusing on two classes of high-redshift galaxy which are believed to
be the progenitors of today's massive ellipticals: {1} our
recently-studied deep sample of 158 "extremely red objects" {EROs};
{2} a complete flux-limited sample of 14 SCUBA sub-mm sources, which
may represent the formation episode of the most massive galaxies at
high redshift. The basic goals are to go deep enough to obtain
morphological parameters for this large sample {e.g. scale-lengths and
shape parameters} to investigate whether, for example, the EROs have
sizes comparable to present day elliptical galaxies. Likewise, what
are the typical size scales and morphologies for the SCUBA sources?
Can we visualize their formation from smaller fragments? We can
achieve both goals in a single contiguous field with a mosaic of 8
deep ACS WFC fields, requiring 16 orbits.

ACS/HRC 9747

An Imaging Survey of the Statistical Frequency of Binaries Among
Exceptionally-Young Dynamical Families in the Main Asteroid Belt

We propose an ambitious SNAPSHOT program to determine the frequency of
binaries among two very young asteroid families in the Main Belt, with
potentially profound implications. These families {of C- and S-type}
have recently been discovered {Nesvorny et al. 2002, Nature 417, 720},
through dynamical modeling, to have been formed at 5.8 MY and 8.3 MY
ago in catastrophic impact events. This is the first time such precise
and young ages have been assigned to a family. Main-belt binaries are
almost certainly produced by collisions, and we would expect a young
family to have a significantly higher frequency of binaries than the
background, because they may not yet have been destroyed by impact or
longer-term gravitational instabilities. In fact, one of the prime
observables from such an event should be the propensity for
satellites. This is the best way that new numerical models for binary
production by collisions {motivated largely by our ground-based
discoveries of satellites among larger asteroids}, can be validated
and calibrated. HST is the only facility that can be used to search
for binaries among such faint objects {V>17.5}. We will also measure
two control clusters, one being an "old" family, and the other a
collection of background asteroids that do not have a family
association, and further compare with our determined value for the
frequency of large main-belt binaries {2%}. We request visits to 180
targets, using ACS/HRC.

ACS/WFC 9744

HST Imaging of Gravitational Lenses

Gravitational lenses offer unique opportunities to study cosmology,
dark matter, galactic structure, galaxy evolution and quasar host
galaxies. They are also the only sample of galaxies selected based on
their mass rather than their luminosity or surface brightness. While
gravitational lenses can be discovered with ground-based optical and
radio observations, converting them into astrophysical tools requires
HST. HST has demonstrated that it is the only telescope that can in
each case precisely locate the lens galaxy, measure its luminosity,
color and structure, and search for lensed images of the source host
galaxy given the typical image separations of ~1''. We will obtain
ACS/WFC V and I images and NICMOS H images of 21 new lenses never
observed by HST and NICMOS H images of 16 lenses never observed by HST
in the IR. As in previous cycles, we request that the data be made
public immediately.

NIC1/NIC2/STIS/CCD/WFPC2 9738

Spectroscopy and Polarimetry of Mars at Closest Approach

We plan a coordinated program of spectroscopy, imaging, and
spectropolarimetry of Mars during the August 2003 opposition to study
the composition and physical state of surface materials and airborne
aerosols. The observations include {a} Moderate spectral resolution
290 to 570 nm STIS long-slit push-broom imaging spectroscopy of Mars,
to constrain the properties of airborne aerosol particles and to
search for and globally map iron-bearing minerals that are diagnostic
of specific past climatic conditions; {b} WFPC2 UV-VIS images designed
primarily to quantify the effects of ice and dust aerosols on our STIS
spectra; {c} NICMOS near-IR images to search for and globally map the
presence of hydrated surface minerals; and {d} ACS multispectral
polarizer images to provide critical phase function measurements
needed to constrain the physical properties of the Martian surface
layer. The observations are timed to take advantage of the closest
approach of Mars to Earth for the next several hundred years. Images
and spectra will be acquired at a spatial scale comparable to existing
spacecraft orbital spectroscopy data {~10 km/pixel} and in wavelength
regions not sampled by past or current Mars spacecraft
instrumentation. These observations also provide complementary
scientific and calibration measurements in support of current and
future NASA and ESA Mars exploration missions.

STIS/CCD/MA1 9724

Towards a global understanding of accretion physics - Clues from an UV
spectroscopic survey of cataclysmic variables

Accretion inflows and outflows are fundamental phenomena in a wide
variety of astrophysical environments, such as Young Stellar Objects,
galactic binaries, and AGN. Observationally, cataclysmic variables
{CVs} are particularly well suited for the study of accretion
processes. We are currently carrying out a Cycle 11 STIS UV
spectroscopic snapshot survey of CVs to fully exploit the diagnostic
potential of these objects for our understanding of accretion physics.
While the data obtained so far are of excellent quality, the number of
targets that will be observed in Cycle 11 is too small for a
statistically significant analysis {only 19 objects out of our 149
accepted Cycle 11 snapshot targets have been observed at the time of
writing}. We propose here to extend this survey into Cycle 12,
building a homogenous database of accretion disc and wind outflow
spectra covering a wide range of mass transfer rates and binary
inclinations. We will analyze these spectra with state-of-the-art
accretion disc model spectra {SYNDISK}, testing our current knowledge
of the accretion disc structure, and, thereby, providing new insight
into the so far not well understood process of viscous dissipation. We
will use our parameterised wind model PYTHON for the analysis of the
radiation driven accretion disc wind spectra, assessing the
fundamental question whether the mass loss rate correlates with the
disc luminosity. In addition, our survey data will identify a number
of systems in which the white dwarf significantly contributes to the
UV flux, permitting an analysis of the impact of mass accretion on the
evolution of these compact stars. This survey will triple the number
of currently available high-quality accretion disc / wind outflow /
accreting white dwarf spectra, and we waive our proprietary rights to
permit a timely use of this database.

WFPC2 9712

Pure Parallel Near-UV Observations with WFPC2 within High-Latitude ACS
Survey Fields

In anticipation of the allocation of ACS high-latitude imaging
survey{s}, we request a modification of the default pure parallel
program for those WFPC2 parallels that fall within the ACS survey
field. Rather than duplicate the red bands which will be done much
better with ACS, we propose to observe in the near-ultraviolet F300W
filter. These data will enable study of the rest-frame ultraviolet
morphology of galaxies at 0<z<1. We will determine the morphological
k-correction, and the location of star formation within galaxies,
using a sample that is likely to be nearly complete with
multi-wavelength photometry and spectroscopic redshifts. The results
can be used to interpret observations of higher redshift galaxies by
ACS.

WFPC2 9710

POMS Test Proposal: WFII backup parallel archive proposal

This is a POMS test proposal designed to simulate scientific plans.

WFPC2 9709

POMS Test Proposal: WFII parallel archive proposal

This is the generic target version of the WFPC2 Archival Pure Parallel
program. The program will be used to take parallel images of random
areas of the sky, following the recommendations of the 2002 Parallels
Working Group.

ACS 9675

CCD Daily Monitor

This program consists of basic tests to monitor, the read noise, the
development of hot pixels and test for any source of noise in ACS CCD
detectors. This programme will be executed once a day for the entire
lifetime of ACS.

ACS 9658

ACS Earth Flats

This program will obtain sequences of flat field images by observing
the bright Earth. Several UV filters from the interim calibration
program {9564} require additional exposures to obtain the required
illumination. A few UV filters from this program will be repeated to
monitor for changes in the flat fields and to verify the interim
results. Since no streaks are observed in the UV, the wavelength
coverage is extended to longer wavelengths in order to explore the
severity of streaks in the flats from clouds in the FOV. We have added
exposures for the HRC in the visible filters to verify the results
derived from the L-flat campaign and to explore the severity of
streaks. We have also added exposures on WFC using the minimum
exposure time and using filters which will not saturate the brightest
WFC pixel by more than 10 times the full well.

ACS 9656

Stability of the ACS CCD: geometry, flat fielding, photometry

A moderately crowded stellar field, located ~6' West of the centre of
the cluster 47 Tuc, is observed repeatedly {every three weeks with the
WFC, every other month with the HRC} in various filters, spending 1
orbit per epoch. Different filters will be used every time, so that
over the course of the year all filters will have been employed at
least twice. The most common filters will be checked more frequently.
The same field has been observed in the course of the SMOV phase and
the positions and magnitudes of the most prominent stars have been
accurately measured. Although the field is neither a proper
astrometric nor a proper photometric standard one, the positions and
magnitudes of the objects in it can be used to monitor any local and
large scale variations in the platescale and sensitivity of the
detectors. It should be noted that for the filters which have already
been used during the SMOV phase it will be sufficient to take one
single image, without CR-SPLIT, since the exposure time is always
short {20-30 sec} and there will be so many stars that the few of them
which are affected by cosmic rays can be discarded as outliers in the
photometry. For narrow and medium band filters not exercised on this
target in the SMOV phase, however, a baseline will have to be set.
This expenditure of time will apply to the current cycle only. At
variance with the approach used in SMOV, there is no need for large
telescope slews to place the same objects on opposite sides of the
detectors, thence allowing the programme to remain compact and
efficient. All exposure level parameters are set to their default
values, except for the amplifier gain of the WFC exposures in the
F606W band, which will be collected with the gain value of 2 for the
WFC for compatibility with the SMOV observations. The exposure time is
typically 30 seconds for the WFC, 60 sec for the HRC. No attempt will
be made to attain a predefined or the same orientation on the sky
amongst different epochs. Typically, for the WFC, five exposures will
be accommodated in one orbit. For the HRC, about 10 exposures can be
fitted within one orbit

STIS 9633

STIS parallel archive proposal - Nearby Galaxies - Imaging and
Spectroscopy

Using parallel opportunities with STIS which were not allocated by the
TAC, we propose to obtain deep STIS imagery with both the Clear
{50CCD} and Long-Pass {F28X50LP} filters in order to make
color-magnitude diagrams and luminosity functions for nearby galaxies.
For local group galaxies, we also include G750L slitless spectroscopy
to search for e.g., Carbon stars, late M giants and S-type stars. This
survey will be useful to study the star formation histories, chemical
evolution, and distances to these galaxies. These data will be placed
immediately into the Hubble Data Archive.

STIS 9608

CCD Bias Monitor - Part 2

Monitor the bias in the 1x1, 1x2, 2x1, and 2x2 bin settings at gain=1,
and 1x1 at gain = 4, to build up high-S/N superbiases and track the
evolution of hot columns.

STIS 9606

CCD Dark Monitor-Part 2

Monitor the darks for the STIS CCD.

WFPC2 9595

WFPC2 CYCLE 11 SUPPLEMENTAL DARKS pt3/3

This dark calibration program obtains 3 dark frames every day to
provide data for monitoring and characterizing the evolution of hot
pixels.

ACS/WFPC2 9481

Pure Parallel Near-UV Observations with WFPC2 within High-Latitude ACS
Survey Fields

In anticipation of the allocation of ACS high-latitude imaging
survey{s}, we request a modification of the default pure parallel
program for those WFPC2 parallels that fall within the ACS survey
field. Rather than duplicate the red bands which will be done much
better with ACS, we propose to observe in the near-ultraviolet F300W
filter. These data will enable study of the rest-frame ultraviolet
morphology of galaxies at 0<z<1. We will determine the morphological
k-correction, and the location of star formation within galaxies,
using a sample that is likely to be nearly complete with
multi-wavelength photometry and spectroscopic redshifts. The results
can be used to interpret observations of higher redshift galaxies by
ACS.

NICMOS 8791

NICMOS Post-SAA calibration - CR Persistence Part 2

A new procedure proposed to alleviate the CR-persistence problem of
NICMOS. Dark frames will be obtained immediately upon exiting the SAA
contour 23, and every time a NICMOS exposure is scheduled within 50
minutes of coming out of the SAA. The darks will be obtained in
parallel in all three NICMOS Cameras. The POST-SAA darks will be
non-standard reference files available to users with a USEAFTER
date/time mark. The keyword 'USEAFTER=date/time' will also be added to
the header of each POST-SAA DARK frame. The keyword must be populated
with the time, in addition to the date, because HST crosses the SAA ~8
times per day so each POST-SAA DARK will need to have the appropriate
time specified, for users to identify the ones they need. Both the raw
and processed images will be archived as POST-SAA DARKSs. Generally we
expect that all NICMOS science/calibration observations started within
50 minutes of leaving an SAA will need such maps to remove the CR
persistence from the science images. Each observation will need its
own CRMAP, as different SAA passages leave different imprints on the
NICMOS detectors.

STIS/CCD 10000

STIS Pure Parallel Imaging Program: Cycle 12

This is the default archival pure parallel program for STIS during
cycle 12.

FLIGHT OPERATIONS SUMMARY:

Significant Spacecraft Anomalies: (The following are preliminary
reports of potential non-nominal performance that will be
investigated.)

HSTAR 9138:  Two FHST Roll Delay Update (U1,3RD) failures @
249/15:15:50Z with Error Box results reading "1 FAILED".  A second
FHST Roll Delay Update (U2RD) failure occurred @ 249/15:42:14Z with
Error Box reading "2 FAILED".  Subsequent Update (U1,2FM) @
249/16:16:17Z occurred while HST was in LOS, results unknown at time. 
Second Update (U1,2FM) @ 249/16:19:02Z was successful.  GS Acquisition
(2,3,2) @ 249/16:22:098Z was successful. Under investigation.

HSTAR 9140:  GS Acquisition (1,2,1) @ 250/14:53:35Z failed to gyro
control after SRLE on FGS 1.  First failure occurred @ 250/14:53:35Z,
second @ 250/14:58:20Z.  Four STIS 710 Status Buffer messages were
received following GS Acquisition failure.  Under investigation.

HSTAR 9141:  GS Acquisition (3,1,3) @ 251/01:55:36Z resulted in FL
backup using FGS 1.  Following GS Acquisition (3,1,3) @ 251/02:49:30Z
also resulted in FL backup on FGS 1.  Prior FM Updates @ 251/01:50:50Z
and 251/01:52Z showed good attitude errors. Under investigation.

COMPLETED OPS REQs: None

OPS NOTES EXECUTED: None

                         SCHEDULED     SUCCESSFUL    FAILURE TIMES
FGS GSacq             27                        26             250/1453z
FGS REacq             21                        21
FHST Update           60                        57             
249/1228z*,
249/1515z, 249/1542z
LOSS of LOCK

Note: (* Only 2nd of two U2,3FM updates at 249/1228z failed; no HSTAR
required)


SIGNIFICANT EVENTS: None






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