HUBBLE
SPACE TELESCOPE - Continuing to Collect World Class Science
DAILY
REPORT #4945
PERIOD
COVERED: 5am October 5 - 5am October 6, 2009 (DOY 278/09:00z-279/09:00z)
OBSERVATIONS
SCHEDULED
ACS/WFC
12043
Post-SM4
Bias Frames for ACS/WFC Subarrays
Differences
between the bias gradients in post-SM4 ACS/WFC full-frame
and
subarray images indicate that full-frame "superbias" calibration
reference
files cannot be used to process subarray images with CALACS.
This
program obtains 1Kx1K and 2Kx2K subarray bias frames that will be
used
to generate superbiases appropriate for calibrating WFC1 and WFC2
subarray
science images obtained at the beginning of Cycle 17.
ACS/WFC3
11586
Exceptional
Galactic Halo Globular Clusters and the Second Parameter
We
propose to obtain deep ACS-WFC images of six globular clusters (five
of
which have no previous HST photometry) that reside in the Galactic
halo,
where the second parameter effect is most pronounced. These
globular
clusters are among the least studied in the Galaxy and yet,
from
the perspective of the second parameter phenomenon, the most
intriguing.
With
the best available CMDs only reaching the vicinity of the main
sequence
turn off at present, the unique sensitivity and resolution of
ACS-WFC
will yield ages of unprecedented precision for these clusters.
These
data will provide us with new insight into the stellar populations
present
in the outer Galactic halo and the nature of the second
parameter.
The second parameter plays a critical role in our
understanding
of the formation and evolution of the Galaxy and the
proposed
observations will shed new light on this problem and these
exceptional
clusters.
ACS/WFC3
11782
Measuring
the Shape and Orientation of the Galactic Dark-Matter Halo
using
Hypervelocity Stars
We
propose to obtain high-resolution images of five hypervelocity stars
in
the Galactic halo in order to establish the first-epoch astrometric
frame
for them, as a part of a long-term program to measure precise
proper
motions. The origin of these recently discovered stars, all with
positive
radial velocities above 540 km/s, is consistent only with being
ejected
from the deep potential well of the massive black hole at the
Galactic
center. The deviations of their space motions from purely
radial
trajectories probe the departures from spherical symmetry of the
Galactic
potential, mainly due to the triaxiality of the dark-matter
halo.
Reconstructing the full three-dimensional space motion of the
hypervelocity
stars, through astrometric proper motions, provides a
unique
opportunity to measure the shape and orientation of the dark
halo.
The hypervelocity stars allow measurement of the potential up to
75
kpc from the center, independently of and at larger distances than
are
afforded by tidal streams of satellite galaxies such as the
Sagittarius
dSph galaxy. HVS3 may be associated with the LMC, rather
then
the Galactic center, and would therefore present a case for a
supermassive
black hole at the center of the LMC. We request one orbit
with
ACS/WFC for each of the five hypervelocity stars to establish their
current
positions relative to background galaxies. We will request a
repeated
observation of these stars in Cycle 17, which will conclusively
measure
the astrometric proper motions.
ACS/WFC3
11879
CCD
Daily Monitor (Part 1)
This
program comprises basic tests for measuring the read noise and dark
current
of the ACS WFC and for tracking the growth of hot pixels. The
recorded
frames are used to create bias and dark reference images for
science
data reduction and calibration. This program will be executed
four
days per week (Mon, Wed, Fri, Sun) for the duration of Cycle 17. To
facilitate
scheduling, this program is split into three proposals. This
proposal
covers 352 orbits (22 weeks) from 31 August 2009 to 31 January
2010.
COS/FUV
11895
FUV
Detector Dark Monitor
The
purpose of this proposal is to 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/NUV
11894
NUV
Detector Dark Monitor
The
purpose of this proposal is to 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.
NIC
11408
NICMOS
Focus and PAM Grid Tilt Tests
The
purpose of this proposal is determine the PAM settings corresponding
to
best focus for NIC1 and NIC2. A test will aslo be done on NIC3 in
order
to establish that the nominal PAM position of -9.5mm relative to
mechanical
zero results in an acceptable focus.
The
program consists of: Visit 01: Focus sweep using NIC1 Visit 02:
Focus
sweep using NIC2 Visit 03: Focus sweep using NIC3 Visit 04: Uplink
of
revised PAM settings (if needed) Visit 05: PAM X/Y grid tilt for NIC1
Visit
06: PAM X/Y grid tilt for NIC2 Visit 07: PAM X/Y grid tilt for
NIC3
Visit 08: Uplink of revised PAM X/Y parameters (if needed)
The
focus sweeps are based on the normal focus monitoring proposal
11320.
The tilt grid measurements are based on proposal 8977 (NIC1) and
9645
(NIC2 and NIC3).
NIC1/NIC2/NIC3
11947
Extended
Dark Monitoring
This
program takes a series of darks to obtain darks (including
amplifier
glow, dark current, and shading profiles) for all three
cameras
in the read-out sequences used in Cycle 17. A set of 12 orbits
will
be observed every two months for a total of 72 orbits for a 12
month
Cycle 17. This is a continuation of Cycle 16 program 11330 scaled
down
by ~80%.
The
first orbit (Visit A0) should be scheduled in the NICMOS SMOV after
the
DC Transfer Test (11406) and at least 36h before the Filter Wheel
Test
(11407). Data download using fast track.
The
following 28 orbits (visit A1-N2) should be scheduled AFTER the SMOV
Proposal
11407 (Filter Wheel Test). This is done in order to monitor the
dark
current following an adjustment of the NCS set-point. These visits
should
be executed until the final temperature is reached during SMOV.
NIC2/WFC3/IR
11548
Infrared
Imaging of Protostars in the Orion A Cloud: The Role of
Environment
in Star Formation
We
propose NICMOS and WFC3/IR 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.
STIS/CCD
11844
CCD
Dark Monitor Part 1
The
purpose of this proposal is to monitor the darks for the STIS CCD.
STIS/CCD
11846
CCD
Bias Monitor-Part 1
The
purpose of this proposal is to 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 deg. C to the ambient instrument
temperature
(~ +5 deg. 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
11852
STIS
CCD Spectroscopic Flats C17
The
purpose of this proposal is to obtain pixel-to-pixel lamp flat
fields
for the STIS CCD in spectroscopic mode.
WFC3/IR
11926
IR
Zero Points
We
will measure and monitor the zeropoints through the IR filters using
observations
of the white dwarf standard stars, GD153, GD71 and GD191B2B
and
the solar analog standard star, P330E. Data will be taken monthly
during
Cycle 17. Observations of the star cluster, NGC 104, are made
twice
to check color transformations. We expect an accuracy of 2% in the
wide
filter zeropoints relative to the HST photometric system, and 5% in
the
medium- and narrow-band filters.
WFC3/UVIS
11565
A
Search for Astrometric Companions to Very Low-Mass, Population II
Stars
We
propose to carry out a Snapshot search for astrometric companions in
a
subsample of very low-mass, halo subdwarfs identified within 120
parsecs
of the Sun. These ultra-cool M subdwarfs are local
representatives
of the lowest-mass H burning objects from the Galactic
Population
II. The expected 3-4 astrometric doubles that will be
discovered
will be invaluable in that they will be the first systems
from
which gravitational masses of metal-poor stars at the bottom of the
main
sequence can be directly measured.
WFC3/UVIS
11657
The
Population of Compact Planetary Nebulae in the Galactic Disk
We
propose to secure narrow- and broad-band images of compact planetary
nebulae
(PNe) in the Galactic Disk to study the missing link of the
early
phases of post-AGB evolution. Ejected AGB envelopes become PNe
when
the gas is ionized. PNe expand, and, when large enough, can be
studied
in detail from the ground. In the interim, only the HST
capabilities
can resolve their size, morphology, and central stars. Our
proposed
observations will be the basis for a systematic study of the
onset
of morphology. Dust properties of the proposed targets will be
available
through approved Spitzer/IRS spectra, and so will the
abundances
of the alpha- elements. We will be able thus to explore the
interconnection
of morphology, dust grains, stellar evolution, and
populations.
The target selection is suitable to explore the nebular and
stellar
properties across the galactic disk, and to set constraints on
the
galactic evolutionary models through the analysis of metallicity and
population
gradients.
WFC3/UVIS
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 and dark frames. A smaller set of 2Kx4K
subarray
biases are acquired at less frequent intervals throughout the
cycle
to support subarray science observations. The internals from this
proposal,
along with those from the anneal procedure (Proposal 11909),
will
be used to generate the necessary superbias and superdark reference
files
for the calibration pipeline (CDBS).
WFC3/UVIS/IR
11644
A
Dynamical-Compositional Survey of the Kuiper Belt: A New Window Into
the
Formation of the Outer Solar System
The
eight planets overwhelmingly dominate the solar system by mass, but
their
small numbers, coupled with their stochastic pasts, make it
impossible
to construct a unique formation history from the dynamical or
compositional
characteristics of them alone. In contrast, the huge
numbers
of small bodies scattered throughout and even beyond the
planets,
while insignificant by mass, provide an almost unlimited number
of
probes of the statistical conditions, history, and interactions in
the
solar system. To date, attempts to understand the formation and
evolution
of the Kuiper Belt have largely been dynamical simulations
where
a hypothesized starting condition is evolved under the
gravitational
influence of the early giant planets and an attempt is
made
to reproduce the current observed populations. With little
compositional
information known for the real Kuiper Belt, the test
particles
in the simulation are free to have any formation location and
history
as long as they end at the correct point. Allowing compositional
information
to guide and constrain the formation, thermal, and
collisional
histories of these objects would add an entire new dimension
to
our understanding of the evolution of the outer solar system. While
ground
based compositional studies have hit their flux limits already
with
only a few objects sampled, we propose to exploit the new
capabilities
of WFC3 to perform the first ever large-scale
dynamical-compositional
study of Kuiper Belt Objects (KBOs) and their
progeny
to study the chemical, dynamical, and collisional history of the
region
of the giant planets. The sensitivity of the WFC3 observations
will
allow us to go up to two magnitudes deeper than our ground based
studies,
allowing us the capability of optimally selecting a target list
for
a large survey rather than simply taking the few objects that can be
measured,
as we have had to do to date. We have carefully constructed a
sample
of 120 objects which provides both overall breadth, for a general
understanding
of these objects, plus a large enough number of objects in
the
individual dynamical subclass to allow detailed comparison between
and
within these groups. These objects will likely define the core
Kuiper
Belt compositional sample for years to come. While we have many
specific
results anticipated to come from this survey, as with any
project
where the field is rich, our current knowledge level is low, and
a
new instrument suddenly appears which can exploit vastly larger
segments
of the population, the potential for discovery -- both
anticipated
and not -- is extraordinary.
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
12
12
FGS
REAcq
03
03
OBAD
with Maneuver
08
08
SIGNIFICANT
EVENTS: (None)