HUBBLE
SPACE TELESCOPE - Continuing to Collect World Class Science
DAILY
REPORT #5117
PERIOD
COVERED: 5am June 14 - 5am June 15, 2010 (DOY 165/09:00z-166/09:00z)
FLIGHT
OPERATIONS SUMMARY:
Significant
Spacecraft Anomalies: (The following are preliminary reports
of
potential non-nominal performance that will be investigated.)
HSTARS:
12302
- GSAcq(1,2,1) scheduled at 166/05:02:06z and REAcqs(1,2,1) at
166/06:33:31z and at 166/08:09:26z all resulted in fine lock
backup
(1,0,1) using FGS 1.
Observations possibly affected: COS 16 -21 Proposal ID#11598; WFC3
44, 46, 49
Proposal ID#11700; WFC3 45, 47, 48, 50, 51 Proposal ID#11906; STIS
16 - 17
Proposal ID#11849.
COMPLETED
OPS REQUEST: (None)
COMPLETED
OPS NOTES: (None)
SCHEDULED SUCCESSFUL
FGS
GSAcq 12 12
FGS
REAcq 5 5
OBAD
with Maneuver 7 7
SIGNIFICANT
EVENTS: (None)
OBSERVATIONS
SCHEDULED:
ACS/SBC
12016
The
Stars and Edge-on Disks of PDS 144: An Intermediate-Mass Analog of
Wide
T Tauri Multiple Stars
High-Inclination
PMS stars are optimally oriented to measure disk size,
height,
to detect jets, and to directly probe disk composition. Placing
these
data into evolutionary context requires dates for the systems and
measurements
of L bol, and extinction. For such stars, X-ray data
provide
L x, but also N(H) and the total extinction. FUV data measures L
UV,
and constrains the shape of the extinction curve. Recent studies
have
suggested that the frequency of Jovian-mass planets is higher for
systems
with intermediate-mass stars, due to disk mass or composition.
While
suitable low mass YSOs are well-represented in the Chandra and HST
archives,
similar data are lacking for higher mass systems. We propose
joint
Chandra and HST imaging of PDS 144 to fill this gap.
COS/FUV
11895
FUV
Detector Dark Monitor
Monitor
the FUV detector dark rate by taking long science exposures
without
illuminating the detector. The detector dark rate and spatial
distribution
of counts will be compared to pre-launch and SMOV data in
order
to verify the nominal operation of the detector. Variations of
count
rate as a function of orbital position will be analyzed to find
dependence
of dark rate on proximity to the SAA. Dependence of dark rate
as
function of time will also be tracked.
COS/FUV/COS/NUV
11598
How
Galaxies Acquire their Gas: A Map of Multiphase Accretion and
Feedback
in Gaseous Galaxy Halos
We
propose to address two of the biggest open questions in galaxy
formation
- how galaxies acquire their gas and how they return it to the
IGM
- with a concentrated COS survey of diffuse multiphase gas in the
halos
of SDSS galaxies at z = 0.15 - 0.35. Our chief science goal is to
establish
a basic set of observational facts about the physical state,
metallicity,
and kinematics of halo gas, including the sky covering
fraction
of hot and cold material, the metallicity of infall and
outflow,
and correlations with galaxy stellar mass, type, and color -
all
as a function of impact parameter from 10 - 150 kpc. Theory suggests
that
the bimodality of galaxy colors, the shape of the luminosity
function,
and the mass-metallicity relation are all influenced at a
fundamental
level by accretion and feedback, yet these gas processes are
poorly
understood and cannot be predicted robustly from first
principles.
We lack even a basic observational assessment of the
multiphase
gaseous content of galaxy halos on 100 kpc scales, and we do
not
know how these processes vary with galaxy properties. This ignorance
is
presently one of the key impediments to understanding galaxy
formation
in general. We propose to use the high-resolution gratings
G130M
and G160M on the Cosmic Origins Spectrograph to obtain sensitive
column
density measurements of a comprehensive suite of multiphase ions
in
the spectra of 43 z < 1 QSOs lying behind 43 galaxies selected from
the
Sloan Digital Sky Survey. In aggregate, these sightlines will
constitute
a statistically sound map of the physical state and
metallicity
of gaseous halos, and subsets of the data with cuts on
galaxy
mass, color, and SFR will seek out predicted variations of gas
properties
with galaxy properties. Our interpretation of these data will
be
aided by state-of-the-art hydrodynamic simulations of accretion and
feedback,
in turn providing information to refine and test such models.
We
will also use Keck, MMT, and Magellan (as needed) to obtain optical
spectra
of the QSOs to measure cold gas with Mg II, and optical spectra
of
the galaxies to measure SFRs and to look for outflows. In addition to
our
other science goals, these observations will help place the Milky
Way's
population of multiphase, accreting High Velocity Clouds (HVCs)
into
a global context by identifying analogous structures around other
galaxies.
Our program is designed to make optimal use of the unique
capabilities
of COS to address our science goals and also generate a
rich
dataset of other absorption-line systems along a significant total
pathlength
through the IGM (Delta z ~ 20).
COS/NUV
11538
COS-GTO:
Imaging of Mid-UV Emissions from Io in Eclipse
The
atmosphere and corona of Jupiter's volcanic moon Io emit light at a
wide
variety of wavelengths, from FUV neutral O and S lines to SO
emission
at 1.7 microns. These emissions provide important constraints
on
the distribution and chemistry of Io's atmosphere, and Io's
interaction
with the Jovian magnetosphere. The neutral O and S FUV
emissions,
shortward of 2000?, have been imaged extensively by HST/STIS
and
visible emissions (from neutral Na, K and O line emission, and SO2
continuum
emission) have been imaged by the Galileo, Cassini, and New
Horizons
spacecraft, but the spatial distribution of emissions in the
2000-3000?
region, thought to be dominated by SO2 electron impact
continuum
emission, has not yet been determined. Earlier long-slit
observations
with STIS indicated strong concentration of 2800? emission
over
the active volcano Prometheus (Jessup et al. 2004), suggesting
local
volcanic control, but Cassini images suggest that the SO2
continuum
seen at longer wavelengths is instead concentrated over the
sub-Jovian
and anti-Jovian points where there are magnetic connections
between
Io and the Jovian magnetosphere- the anti-Jovian point is close
to
Prometheus. A series of 200-second integrations taken in Jupiter
eclipse
should determine whether emission is concentrated over volcanos
or
over the sub-Jovian point, and should be able to observe motion of
the
emission due to changing magnetic field orientation if it is
magnetically
controlled. This observation will also provide experience
in
the use of COS in imaging mode.
COS/NUV
11894
NUV
Detector Dark Monitor
Measure
the NUV detector dark rate by taking long science exposures with
no
light on the detector. The detector dark rate and spatial
distribution
of counts will be compared to pre-launch and SMOV data in
order
to verify the nominal operation of the detector. Variations of
count
rate as a function of orbital position will be analyzed to find
dependence
of dark rate on proximity to the SAA. Dependence of dark rate
as
function of time will also be tracked.
S/C/WFC3/IR
11929
IR
Dark Current Monitor
Analyses
of ground test data showed that dark current signals are more
reliably
removed from science data using darks taken with the same
exposure
sequences as the science data, than with a single dark current
image
scaled by desired exposure time. Therefore, dark current images
must
be collected using all sample sequences that will be used in
science
observations. These observations will be used to monitor changes
in
the dark current of the WFC3-IR channel on a day-to-day basis, and to
build
calibration dark current ramps for each of the sample sequences to
be
used by GOs in Cycle 17. For each sample sequence/array size
combination,
a median ramp will be created and delivered to the
calibration
database system (CDBS).
STIS/CCD
11721
Verifying
the Utility of Type Ia Supernovae as Cosmological Probes:
Evolution
and Dispersion in the Ultraviolet Spectra
The
study of distant type Ia supernova (SNe Ia) offers the most
practical
and immediate discriminator between popular models of dark
energy.
Yet fundamental questions remain over possible
redshift-dependent
trends in their observed and intrinsic properties.
High
quality Keck spectroscopy of a representative sample of 36
intermediate
redshift SNe Ia has revealed a surprising, and unexplained,
diversity
in their rest-frame UV fluxes. One possible explanation is
hitherto
undiscovered variations in the progenitor metallicity.
Unfortunately,
this result cannot be compared to local UV data as only
two
representative SNe Ia have been studied near maximum light. Taking
advantage
of two new `rolling searches' and the restoration of STIS, we
propose
a non-disruptive TOO campaign to create an equivalent comparison
local
sample. This will allow us to address possible evolution in the
mean
UV spectrum and its diversity, an essential precursor to the study
of
SNe beyond z~1.
STIS/CCD
11818
NICMOS
confirmation of an extrasolar planet candidate directly detected
with
ACS
With
ACS/HRC coronagraphy, we have achieved the direct detection of a
planet
candidate in F606W and F814W around a bright nearby star with a
debris
belt. The planet candidate, Fomalhaut b, lies 18 astronomical
units
interior to the dust belt and we detect counterclockwise orbital
motion
in observations separated by 1.75 years. The candidate has mass
no
greater than three Jupiter masses based on an analysis of its
luminosity
and the dynamical argument that a significantly more massive
object
would disrupt the dust belt. Using recent model predictions for
100-300
Myr old planetary atmospheres, the planet candidate has a
temperature
of ~400 K and a mass 1.6 - 3.4 M_J. Variability at optical
wavelengths
suggests additional sources of luminosity such as H-alpha
emission
or the episodic accretion of cometary material. Here we propose
follow-up
observations with HST/STIS c oronagraphy. We employ an
observing
strategy that is identical to the one used for the detection
using
ACS/HRC coronagraphy. The key goal is recovery of Fomalhaut b in a
third
epoch that will also provide crucial astrometric information to
determine
its orbit. From the new orbit estimate and models of dynamical
interactions
with the surrounding debris belt, we aim to further
constrain
the mass of Fomalhaut b and the evolutionary history of the
system.
STIS/CCD
11845
CCD
Dark Monitor Part 2
Monitor
the darks for the STIS CCD.
STIS/CCD
11847
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/CCD
11849
STIS
CCD Hot Pixel Annealing
This
purpose of this activity is to repair radiation induced hot pixel
damage
to the STIS CCD by warming the CCD to the ambient instrument
temperature
and annealing radiation damaged pixels. Radiation damage
creates
hot pixels in the STIS CCD Detector. Many of these hot pixels
can
be repaired by warming the CCD from its normal operating temperature
near
-83 C to the ambient instrument temperature (~ +5 C) for several
hours.
The number of hot pixels repaired is a function of annealing
temperature.
The effectiveness of the CCD hot pixel annealing process is
assessed
by measuring the dark current behavior before and after
annealing
and by searching for any window contamination effects.
STIS/CCD/STIS/MA2
11568
A
SNAPSHOT Survey of the Local Interstellar Medium: New NUV Observations
of
Stars with Archived FUV Observations
We
propose to obtain high-resolution STIS E230H SNAP observations of
MgII
and FeII interstellar absorption lines toward stars within 100
parsecs
that already have moderate or high-resolution far-UV (FUV),
900-1700
A, observations available in the MAST Archive. Fundamental
properties,
such as temperature, turbulence, ionization, abundances, and
depletions
of gas in the local interstellar medium (LISM) can be
measured
by coupling such observations. Due to the wide spectral range
of
STIS, observations to study nearby stars also contain important data
about
the LISM embedded within their spectra. However, unlocking this
information
from the intrinsically broad and often saturated FUV
absorption
lines of low-mass ions, (DI, CII, NI, OI), requires first
understanding
the kinematic structure of the gas along the line of
sight.
This can be achieved with high resolution spectra of high-mass
ions,
(FeII, MgII), which have narrow absorption lines, and can resolve
each
individual velocity component (interstellar cloud). By obtaining
short
(~10 minute) E230H observations of FeII and MgII, for stars that
already
have moderate or high-resolution FUV spectra, we can increase
the
sample of LISM measurements, and thereby expand our knowledge of the
physical
properties of the gas in our galactic neighborhood. STIS is the
only
instrument capable of obtaining the required high resolution data
now
or in the foreseeable future.
WFC3/IR
11694
Mapping
the Interaction between High-Redshift Galaxies and the
Intergalactic
Environment
With
the commissioning of the high-throughput large-area camera WFC3/IR,
it
is possible for the first time to undertake an efficient survey of
the
rest-frame optical morphologies of galaxies at the peak epoch of
star
formation in the universe. We therefore propose deep WFC3/IR
imaging
of over 320 spectroscopically confirmed galaxies between
redshift
1.6 < z < 3.4 in well-studied fields which lie along the line
of
sight to bright background QSOs. The spectra of these bright QSOs
probe
the IGM in the vicinity of each of the foreground galaxies along
the
line of sight, providing detailed information on the physical state
of
the gas at large galactocentric radii. In combination with our
densely
sampled UV/IR spectroscopy, stellar population models, and
kinematic
data in these fields, WFC3/IR imaging data will permit us to
construct
a comprehensive picture of the structure, dynamics, and star
formation
properties of a large population of galaxies in the early
universe
and their effect upon their cosmological environment.
WFC3/IR
11719
A
Calibration Database for Stellar Models of Asymptotic Giant Branch
Stars
Studies
of galaxy formation and evolution rely increasingly on the
interpretation
and modeling of near-infrared observations. At these
wavelengths,
the brightest stars are intermediate mass asymptotic giant
branch
(AGB) stars. These stars can contribute nearly 50% of the
integrated
luminosity at near infrared and even optical wavelengths,
particularly
for the younger stellar populations characteristic of
high-redshift
galaxies (z>1). AGB stars are also significant sources of
dust
and heavy elements. Accurate modeling of AGB stars is therefore of
the
utmost importance.
The
primary limitation facing current models is the lack of useful
calibration
data. Current models are tuned to match the properties of
the
AGB population in the Magellanic Clouds, and thus have only been
calibrated
in a very narrow range of sub-solar metallicities.
Preliminary
observations already suggest that the models are
overestimating
AGB lifetimes by factors of 2-3 at lower metallicities.
At
higher (solar) metallicities, there are no appropriate observations
for
calibrating the models.
We
propose a WFC3/IR SNAP survey of nearby galaxies to create a large
database
of AGB populations spanning the full range of metallicities and
star
formation histories. Because of their intrinsically red colors and
dusty
circumstellar envelopes, tracking the numbers and bolometric
fluxes
of AGB stars requires the NIR observations we propose here. The
resulting
observations of nearby galaxies with deep ACS imaging offer
the
opportunity to obtain large (100-1000's) complete samples of AGB
stars
at a single distance, in systems with well-constrained star
formation
histories and metallicities.
WFC3/IR
11929
IR
Dark Current Monitor
Analyses
of ground test data showed that dark current signals are more
reliably
removed from science data using darks taken with the same
exposure
sequences as the science data, than with a single dark current
image
scaled by desired exposure time. Therefore, dark current images
must
be collected using all sample sequences that will be used in
science
observations. These observations will be used to monitor changes
in
the dark current of the WFC3-IR channel on a day-to-day basis, and to
build
calibration dark current ramps for each of the sample sequences to
be
used by GOs in Cycle 17. For each sample sequence/array size
combination,
a median ramp will be created and delivered to the
calibration
database system (CDBS).
WFC3/UVI
11577
Opening
New Windows on the Antennae with WFC3
We
propose to use WFC3 to provide key observations of young star
clusters
in "The Antennae" (NGC4038/39). Of prime importance is the
WFC3's
ability to push the limiting UV magnitude FIVE mag deeper than
our
previous WFPC2 observations. This corresponds to pushing the
limiting
cluster mass from ~10**5 to ~10**3 solar masses for cluster
ages
~10**8 yrs. In addition, the much wider field of view of the WFC3
IR
channel will allow us to map out both colliding disks rather than
just
the Overlap Region between them. This will be especially important
for
finding the youngest clusters that are still embedded in their
placental
cocoons. The extensive set of narrow-band filters will provide
an
effective means for determining the properties of shocks, which are
believed
to be a primary triggering mechanism for star formation. We
will
also use ACS in parallel with WFC3 to observe portions of both the
northern
and southern tails at no additional orbital cost. Finally, one
additional
primary WFC3 orbit will be used to supplement exisiting HST
observations
of the star-forming "dwarf" galaxy at the end of the
southern
tail. Hence, when completed we will have full UBVI + H_alpha
coverage
(or more for the main galaxy) of four different environments in
the
Antennae. In conjunction with the extensive multi-wavelength
database
we have collected (both HST and ground-based) these
observations
will provide answers to fundamental questions such as: How
do
these clusters form and evolve? How is star formation triggered? How
do
star clusters affect the local and global ISM, and the evolution of
the
galaxy as a whole? The Antennae galaxies are the nearest example of
a
major disk--disk merger, and hence may represent our best chance for
understanding
how mergers form tremendous numbers of clusters and stars,
both
in the local universe and during galaxy assembly at high redshift.
WFC3/UVI
11700
Bright
Galaxies at z>7.5 with a WFC3 Pure Parallel Survey
The
epoch of reionization represents a special moment in the history of
the
Universe as it is during this era that the first galaxies and star
clusters
are formed. Reionization also profoundly affects the
environment
where subsequent generations of galaxies evolve. Our
overarching
goal is to test the hypothesis that galaxies are responsible
for
reionizing neutral hydrogen. To do so we propose to carry out a pure
parallel
WFC3 survey to constrain the bright end of the redshift z>7.5
galaxy
luminosity function on a total area of 176 arcmin^2 of sky.
Extrapolating
the evolution of the luminosity function from z~6, we
expect
to detect about 20 Lyman Break Galaxies brighter than M_* at z~8
significantly
improving the current sample of only a few galaxies known
at
these redshifts. Finding significantly fewer objects than predicted
on
the basis of extrapolation from z=6 would set strong limits to the
brightness
of M_*, highlighting a fast evolution of the luminosity
function
with the possible implication that galaxies alone cannot
reionize
the Universe. Our observations will find the best candidates
for
spectroscopic confirmation, that is bright z>7.5 objects, which
would
be missed by small area deeper surveys. The random pointing nature
of
the program is ideal to beat cosmic variance, especially severe for
luminous
massive galaxies, which are strongly clustered. In fact our
survey
geometry of 38 independent fields will constrain the luminosity
function
like a contiguous single field survey with two times more area
at
the same depth. Lyman Break Galaxies at z>7.5 down to m_AB=26.85 (5
sigma)
in F125W will be selected as F098M dropouts, using three to five
orbits
visits that include a total of four filters (F606W, F098M, F125W,
F160W)
optimized to remove low-redshift interlopers and cool stars. Our
data
will be highly complementary to a deep field search for high-z
galaxies
aimed at probing the faint end of the luminosity function,
allowing
us to disentangle the degeneracy between faint end slope and
M_*
in a Schechter function fit of the luminosity function. We waive
proprietary
rights for the data. In addition, we commit to release the
coordinates
and properties of our z>7.5 candidates within one month from
the
acquisition of each field.
WFC3/UVI
11707
Detecting
Isolated Black Holes through Astrometric Microlensing
This
proposal aims to make the first detection of isolated stellar-mass
black
holes (BHs) in the Milky Way, and to determine their masses. Until
now,
the only directly measured BH masses have come from radial-velocity
measurements
of X-ray binaries. Our proposed method uses the astrometric
shifts
that occur when a Galactic-bulge microlensing event is caused by
a
BH lens. Out of the hundreds of bulge microlensing events found
annually
by the OGLE and MOA surveys, a few are found to have very long
durations
(>200 days). It is generally believed that the majority of
these
long-duration events are caused by lenses that are isolated BHs.
To
test this hypothesis, we will carry out high-precision astrometry of
5
long-duration events, using the ACS/HRC camera. The expected
astrometric
signal from a BH lens is >1.4 mas, at least 7 times the
demonstrated
astrometric precision attainable with the HRC.
This
proposal will thus potentially lead to the first unambiguous
detection
of isolated stellar-mass BHs, and the first direct mass
measurement
for isolated stellar-mass BHs through any technique.
Detection
of several BHs will provide information on the frequency of
BHs
in the Galaxy, with implications for the slope of the IMF at high
masses,
the minimum mass of progenitors that produce BHs, and
constraints
on theoretical models of BH formation.
WFC3/UVI
11905
WFC3
UVIS CCD Daily Monitor
The
behavior of the WFC3 UVIS CCD will be monitored daily with a set of
full-frame,
four-amp bias<BR>and dark frames. A smaller set of 2Kx4K
subarray
biases are acquired at less frequent intervals<BR>throughout
the
cycle to support subarray science observations. The internals from
this
proposal,<BR>along with those from the anneal procedure (11909),
will
be used to generate the necessary superbias<BR>and superdark
reference
files for the calibration pipeline (CDBS).
WFC3/UVI
11906
WFC3
UVIS CCD Gain
The
absolute gain of each quadrant of the WFC3 UVIS detector will be
measured
for the nominal detector readout configuration and at the
on-orbit
operating temperature.
WFC3/UVI
11912
UVIS
Internal Flats
This
proposal will be used to assess the stability of the flat field
structure
for the UVIS detector throughout the 15 months of Cycle 17.
The
data will be used to generate on-orbit updates for the delta-flat
field
reference files used in the WFC3 calibration pipeline, if
significant
changes in the flat structure are seen.