Notice: For the foreseeable future, the daily reports may
contain
apparent discrepancies between some proposal descriptions
and the listed
instrument usage. This is due to the conversion of
previously approved
ACS WFC or HRC observations into WFPC2, or NICMOS
observations
subsequent to the loss of ACS CCD science capability in
late January.
HUBBLE SPACE TELESCOPE - Continuing to collect World Class
Science
DAILY REPORT # 4348
PERIOD COVERED: UT April 24, 2007 (DOY 114)
OBSERVATIONS SCHEDULED
ACS/SBC 10862
Comprehensive Auroral Imaging of Jupiter and Saturn during
the
International Heliophysical Year
A comprehensive set of observations of the auroral
emissions from
Jupiter and Saturn is proposed for the International
Heliophysical Year
in 2007, a unique period of especially concentrated
measurements of
space physics phenomena throughout the solar system. We
propose to
determine the physical relationship of the various auroral
processes at
Jupiter and Saturn with conditions in the solar wind at
each planet.
This can be accomplished with campaigns of observations,
with a sampling
interval not to exceed one day, covering at least one
solar rotation.
The solar wind plasma density approaching Jupiter will be
measured by
the New Horizons spacecraft, and a separate campaign near
opposition in
May 2007 will determine the effect of large-scale
variations in the
interplanetary magnetic field {IMF} on the Jovian aurora
by
extrapolation from near-Earth solar wind measurements. A
similar Saturn
campaign near opposition in Jan. 2007 will combine
extrapolated solar
wind data with measurements from a wide range of locations
within the
Saturn magnetosphere by Cassini. In the course of making
these
observations, it will be possible to fully map the auroral
footprints of
Io and the other satellites to determine both the local
magnetic field
geometry and the controlling factors in the
electromagnetic interaction
of each satellite with the corotating magnetic field and
plasma density.
Also in the course of making these observations, the
auroral emission
properties will be compared with the properties of the
near-IR
ionospheric emissions {from ground-based observations} and
non thermal
radio emissions, from ground-based observations for
Jupiter?s decametric
radiation and Cassini plasma wave measurements of the
Saturn Kilometric
Radiation {SKR}.
ACS/SBC 11074
ACS/SBC Darks in Support of Specific SBC Science
Observations
This program provides SBC DARK visits to be scheduled in
conjuction with
certain specific science observations which require the
SBC to be turned
on in the orbit preceeding the science observation.
WFPC2 10917
Afterglows and Environments of Short-Hard Gamma-Ray Bursts
Discovery of the first afterglows of short-hard bursts
{SHBs} has led to
a revolution in our understanding of these events,
strongly suggesting
that they originate in the mergers of compact-object
binaries.
Capitalizing on this progress, we propose to pursue the
next generation
of SHB observations with HST, tracking the decay of all
accessible SHB
afterglows to late times and pinpointing the location of
several more
within the context of their host galaxies. These
observations will allow
quantitative analysis of progenitor lifetimes and short
burst
environments, enable direct confrontation with population
synthesis
models, and provide updated event rate estimates for the
LIGO and VIRGO
gravitational-wave detectors that are now coming on-line.
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 10890
Morphologies of the Most Extreme High-Redshift
Mid-IR-Luminous Galaxies
The formative phase of the most massive galaxies may be
extremely
luminous, characterized by intense star- and
AGN-formation. Till now,
few such galaxies have been unambiguously identified at
high redshift,
restricting us to the study of low-redshift ultraluminous
infrared
galaxies as possible analogs. We have recently discovered
a sample of
objects which may indeed represent this early phase in
galaxy formation,
and are undertaking an extensive multiwavelength study of
this
population. These objects are bright at mid-IR wavelengths
{F[24um]>0.8mJy}, but deep ground based imaging
suggests extremely faint
{and in some cases extended} optical counterparts
{R~24-27}. Deep K-band
images show barely resolved galaxies. Mid-infrared
spectroscopy with
Spitzer/IRS reveals that they have redshifts z ~ 2-2.5,
suggesting
bolometric luminosities ~10^{13-14}Lsun! We propose to
obtain deep ACS
F814W and NIC2 F160W images of these sources and their environs
in order
to determine kpc-scale morphologies and surface photometry
for these
galaxies. The proposed observations will help us determine
whether these
extreme objects are merging systems, massive obscured
starbursts {with
obscuration on kpc scales!} or very reddened {locally
obscured} AGN
hosted by intrinsically low-luminosity galaxies.
WFPC2 11083
The Structure, Formation and Evolution of Galactic Cores
and Nuclei
A surprising result has emerged from the ACS Virgo Cluster
Survey
{ACSVCS}, a program to obtain ACS/WFC gz imaging for a
large, unbiased
sample of 100 early-type galaxies in the Virgo Cluster. On
subarcsecond
scales {i.e., <0.1"-1"}, the HST brightness
profiles vary systematically
from the brightest giants {which have nearly constant
surface brightness
cores} to the faintest dwarfs {which have compact stellar
nuclei}.
Remarkably, the fraction of galaxy mass contributed by the
nuclei in the
faint galaxies is identical to that contributed by
supermassive black
holes in the bright galaxies {0.2%}. These findings
strongly suggest
that a single mechanism is responsible for both types of
Central Massive
Object: most likely internally or externally modulated gas
inflows that
feed central black holes or lead to the formation of
"nuclear star
clusters". Understanding the history of gas
accretion, star formation
and chemical enrichment on subarcsecond scales has thus
emerged as the
single most pressing question in the study of nearby
galactic nuclei,
either active or quiescent. We propose an ambitious HST
program {199
orbits} that constitutes the next, obvious step forward:
high-resolution, ultraviolet {WFPC2/F255W} and infrared
{NIC1/F160W}
imaging for the complete ACSVCS sample. By capitalizing on
HST's unique
ability to provide high-resolution images with a sharp and
stable PSF at
UV and IR wavelengths, we will leverage the existing
optical HST data to
obtain the most complete picture currently possible for
the history of
star formation and chemical enrichment on these small scales.
Equally
important, this program will lead to a significant
improvement in the
measured structural parameters and density distributions
for the stellar
nuclei and the underlying galaxies, and provide a
sensitive measure of
"frosting" by young stars in the galaxy cores.
By virtue of its superb
image quality and stable PSF, NICMOS is the sole
instrument capable of
the IR observations proposed here. In the case of the
WFPC2
observations, high-resolution UV imaging {< 0.1"}
is a capability unique
to HST, yet one that could be lost at any any time.
FLIGHT OPERATIONS SUMMARY:
Significant Spacecraft Anomalies: (The following are
preliminary reports
of potential non-nominal performance that will be
investigated.)
HSTARS: (None)
COMPLETED OPS REQUEST: (None)
COMPLETED OPS NOTES: (None)
SCHEDULED
SUCCESSFUL
FGS GSacq
09
09
FGS
REacq
05
05
OBAD with Maneuver 28
28
SIGNIFICANT EVENTS:
Evaluation of Universal Kalman Filter performance
continued. Multiple
text segments were executed. Details follow.
The Kalman Filter (KF) was restarted at 114/11:41 (OR
18045-0) during
orbit day, during a vehicle maneuver and during an M2G
guiding interval.
The filter was activated with the MSS and CSS sensor
inputs enabled. All
UKF parameters showed nominal operation. The test was an
MSS/CSS
Initialization Test Case with the vehicle in maneuver and
during a fast
changing B-field (M_C_IVF, Test #5).
Test #9 (M_C_IVP) planned for 114/13:55 was not executed
as the forward
link could not be scheduled. This test will be
rescheduled.
The Gyro-1 sensor input was added to the KF at 114/14:30
(OR 18048-2)
just after EOD during an F2G guiding interval. The filter
was running
with the MSS and CSS sensor inputs enabled and converged.
All UKF
parameters showed nominal operation. The test was an
MSS/CSS/Gyro1 test
case with the Gyro1 sensor input removed at 114/14:59 with
the filter
running. The Gyro1 input was removed during an F2G guiding
interval,
during orbit day and during a fast changing B-field and
with no vehicle
maneuver (MC_G1_HNF, Test #33). The response to the removal
of the gyro
input was nominal and the filter remained converged. The
removal of the
gyro input restored the default MSS/CSS configuration of
the filter.
Test #10 (M_C_INP) was not executed at 114/18:43 as it was
previously
and successfully executed at 113/18:44.
The execution of Test #16 (MC_G1_IVS) replaced Test #6
(M_C_IVS) at
114/20:00 since Test #6 had been previously and
successfully executed at
109/23:34. The KF was restarted at 114/20:00 (OR 18046-0)
during orbit
day, during a vehicle maneuver and during an M2G guiding
interval. The
filter was activated with the MSS, CSS and Gyro1 sensor
inputs enabled.
All UKF parameters showed nominal operation and
convergence. The test
was an MSS/CSS/Gyro1 Initialization test case during a
vehicle maneuver
and during a slow changing B-field. The filter was halted,
the gyro
input selection removed and the filter was restarted at
114/20:22 in the
default MSS/CSS configuration.
At 114/20:31 the gyro input was added to the KF (OR
18048-2) during
orbit night and a T2G guiding interval. The filter was
running with the
MSS and CSS sensor inputs enabled and with the filter
converged. All UKF
parameters showed nominal operation. The test was an
MSS/CSS/Gyro1 test
case with the Gyro1 sensor input removed at 114/21:44 with
the filter
running. The Gyro1 input was removed during an T2G guiding
interval,
during orbit day and during a slow changing B-field
(MC_G1_HNS, Test
#34). The response to the removal of the gyro input was
nominal and the
filter remained converged. The removal of the gyro input
restored the
default MSS/CSS configuration of the filter.
The Kalman Filter was restarted at 114/23:33 (OR 18045-0)
during orbit
night, during a vehicle slew and during an M2G guiding
interval. The
filter was activated with the MSS and CSS sensor inputs
enabled, however
no CSS signal was present due to orbit night. All UKF
parameters showed
nominal convergence and steady-state operation. The test
was an MSS Only
Initialization Test Case with a vehicle maneuver and
during a slow
changing B-field (M_0_IVS, Test #2).
The test above completed testing for the day and left the
KF configured
in the default MSS/CSS mode.