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 # 4370
PERIOD COVERED: UT May 24, 2007 (DOY 144)
OBSERVATIONS SCHEDULED
WFPC2 10877
A Snapshot Survey of the Sites of Recent, Nearby
Supernovae
During the past few years, robotic {or nearly robotic}
searches for
supernovae {SNe}, most notably our Lick Observatory
Supernova Search
{LOSS}, have found hundreds of SNe, many of them in quite
nearby
galaxies {cz < 4000 km/s}. Most of the objects were
discovered before
maximum brightness, and have follow-up photometry and
spectroscopy; they
include some of the best-studied SNe to date. We propose
to conduct a
snapshot imaging survey of the sites of some of these
nearby objects, to
obtain late-time photometry that {through the shape of the
light and
color curves} will help reveal the origin of their
lingering energy. The
images will also provide high-resolution information on
the local
environments of SNe that are far superior to what we can
procure from
the ground. For example, we will obtain color-color and
color-magnitude
diagrams of stars in these SN sites, to determine the SN
progenitor
masses and constraints on the reddening. Recovery of the
SNe in the new
HST images will also allow us to actually pinpoint their
progenitor
stars in cases where pre- explosion images exist in the
HST archive.
This proposal is an extension of our successful Cycle 13
snapshot survey
with ACS. It is complementary to our Cycle 15 archival
proposal, which
is a continuation of our long-standing program to use
existing HST
images to glean information about SN environments.
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}.
WFPC2 10826
Galaxy Evolution During Half the Age of the Universe: ACS
imaging of
rich galaxy clusters
Detailed studies of nearby galaxies {z<0.05} show that
galaxies have
very complex histories of formation and evolution
involving mergers,
bursts of star formation, and morphological changes. Even
so, the global
properties of the galaxies {radii, luminosities, rotation
velocities,
velocity dispersions, and absorption line strengths}
follow a number of
very tight {empirical} scaling relations, e.g. the
Tully-Fisher relation
and the Fundamental Plane {FP}. We use the scaling
relations plus
quantative morphological measures for galaxy clusters up
to z=1 to
constrain models for galaxy evolution. Here we request 24
orbits to
obtain ACS imaging of the remaining three clusters in our
sample at
z~0.7-1.0. High resolution imaging of the clusters is
critical for our
study of star formation histories and structural evolution
in dense
environments since z<1. We have previously obtained
deep spectroscopic
observations of the clusters with Gemini. The data will
provide samples
large enough to establish the slope of the FP for each
cluster. With
multiple clusters at similar redshifts, we can probe
evolutionary
differences within a single epoch in order to decouple
changes due to
different environments. Our two other high-z clusters
exhibit different
chemical enrichment histories, which we argue are due to
the different
merging histories of these clusters.
NIC2 10858
NICMOS Imaging of the z ~ 2 Spitzer Spectroscopic Sample
of
Ultraluminous Infrared Galaxies We propose to obtain
NICMOS images of
the first large sample of high-z ultra-luminous infrared
galaxies
{ULIRGs} whose redshifts and physical states have been
determined with
Spitzer mid-IR spectra. The detection of strong silicate
absorption
and/or PAH emission lines suggest that the these sources
are a mixture
of highly obscured starbursts, AGNs and composite systems
at z=2.
Although some of the spectra show PAH emission similar to
local
starburst ULIRGs, their bolometric luminosities are
roughly an order of
magnitude higher. One important question is if major
mergers, which are
the trigger for 95% of local ULIRGs, also drive this enormous
energy
output observed in our z=2 sample. The NICMOS images will
allow us to
{1} measure surface brightness profiles of z~2 ULIRGs and
establish if
major mergers could be common among our luminous sources
at these early
epochs, {2} determine if starbursts and AGNs classified
based on their
mid-IR spetra would have different morphological
signatures, thus
different dynamic state; {3} make comparisons with the
similar studies
of ULIRGs at z ~ 0 - 1, thus infer any evolutionary
connections between
high-z ULIRGs and the formation of normal, massive
galaxies and quasars
observed today.
WFPC2 10886
The Sloan Lens ACS Survey: Towards 100 New Strong Lenses
As a continuation of the highly successful Sloan Lens ACS
{SLACS} Survey
for new strong gravitational lenses, we propose one orbit
of ACS-WFC
F814W imaging for each of 50 high-probability strong
galaxy-galaxy lens
candidates. These observations will confirm new lens
systems and permit
immediate and accurate photometry, shape measurement, and
mass modeling
of the lens galaxies. The lenses delivered by the SLACS
Survey all show
extended source structure, furnishing more constraints on
the projected
lens potential than lensed-quasar image positions. In
addition, SLACS
lenses have lens galaxies that are much brighter than
their lensed
sources, facilitating detailed photometric and dynamical
observation of
the former. When confirmed lenses from this proposal are
combined with
lenses discovered by SLACS in Cycles 13 and 14, we expect
the final
SLACS lens sample to number 80--100: an approximate
doubling of the
number of known galaxy-scale strong gravitational lenses
and an
order-of-magnitude increase in the number of optical
Einstein rings. By
virtue of its homogeneous selection and sheer size, the
SLACS sample
will allow an unprecedented exploration of the mass
structure of the
early- type galaxy population as a function of all other
observable
quantities. This new sample will be a valuable resource to
the
astronomical community by enabling qualitatively new
strong lensing
science, and as such we will waive all but a short
{3-month} proprietary
period on the observations.
NIC1/NIC2/NIC3 8794
NICMOS Post-SAA calibration - CR Persistence Part 5
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.
WFPC2 10888
Complexity in the Smallest Galaxies: Star Formation
History of the
Sculptor Dwarf Spheroidal
The Sculptor dwarf spheroidal galaxy {Scl dSph} is one of
the most
luminous of the Milky Way dSph satellites, suffers
virtually no
foreground confusion or reddening because of its high
galactic latitude,
and is nearby at 80 kpc from the Sun. It is of great
interest to
astronomy to understand the detailed histories of dSph
galaxies because
they may be survivors of the hierarchical merging process
that created
giant galaxies like our own. Despite this, the age
distribution of stars
in Scl dSph remains remarkably poorly constrained because
of a dearth of
high-quality color-magnitude diagrams {CMDs} of its
central regions. Scl
dSph is known to be complex on the basis of shallower
photometry, radial
velocity studies, and investigations of the metallicity;
however, the
age range of significant star-formation and the proportion
of stars
older and younger than 10 Gyr is still completely unknown.
The age of
the centrally concentrated, metal-rich population has
never been
measured. We propose to obtain deep optical images of the
core of Scl
dSph with WFPC2 in order to measure the temporal evolution
of its
star-formation rate over its entire lifetime. The ONLY way
to reliably
measure the variation in star-formation rate on Gyr
timescales at ages
of 10-13 Gyr is with photometry of a large number of stars
at and below
the oldest main-sequence turnoffs to magnitudes of {B,I} =
{25.1, 24.5}.
Because of the high stellar density and resulting image
crowding, it is
impossible to achieve the required level of photometric
precision except
with diffraction-limited imaging. These data will permit
the first
reliable measurement of the star-formation history of the
main body of
Scl dSph; limited inferences from WFPC2 data in an outer
field have been
made, but they were hindered not only by small number
statistics but by
the subsequent revelation of extremely strong population
gradients in
Scl dSph, such that the stars in the existing WFPC2 field
are not
representative of the galaxy as a whole. Our proposed
program will shed
strong new light on the formation processes of the
smallest galaxies.
Only by measuring the detailed early histories of galaxies
like Scl dSph
can we evaluate the impact of outside influences like
ram-pressure
stripping, tidal stirring, and photoionization feedback on
the evolution
of small galaxies.
FLIGHT OPERATIONS SUMMARY:
Significant Spacecraft Anomalies: (The following are
preliminary reports
of potential non-nominal performance that will be
investigated.)
HSTARS:
10831 - REacq(1,2,1) failed due to search radius limit
exceeded.
REacq(1,2,1) scheduled at 144/12:05:59 failed due to search radius limit
exceeded on FGS 1. OBAD1 showed errors of V1=-26.92, V2=-1645.61,
V3=-27.15, and RSS=1646.06. OBAD2 showed errors of V1=-55.09, V2=-29.53,
V3=-55.84, and RSS=83.81.
COMPLETED OPS REQUEST: (None)
18093-2 - PCS KF OOT Support, 144/13:17 @ 144/13:26z
18090-0 - MSS/CSS Initialization Test#9 for day 144 @
144/13:52z
COMPLETED OPS NOTES: (None)
SIGNIFICANT EVENTS:
Evaluation of Universal Kalman Filter performance
continued Details follow.
Background Kalman Filter Operation:
The KF was halted at 144/13:19. The filter was restarted
at
144/13:25 with the MSS and CSS sensor inputs enabled. The
filter was
restarted during a vehicle slew and just prior to EON
(13:27) to monitor
how the penumbra would effect convergence performance
(M_C_IVP, Test
#9). Only a short period of UKF converged was able to be
monitored due
to the scheduled loss of return telemetry shortly after
EON (data was
captured to the recorder). Subsequent UKF performance was
nominal. The
filter was halted, reconfigured and restarted with only
the MSS sensor
input enabled at 144/13:52.
This test completes the KF convergence testing for the 141
SMS. The
filter will be reconfigured to perform a long-term
monitoring test of
MSS and Gyro1 sensor input (CSS disabled) on Friday due to
the few
opportunities to perform the remaining KF convergence
testing in the 148
SMS.