HUBBLE
SPACE TELESCOPE - Continuing to Collect World Class Science
DAILY
REPORT #5183
PERIOD
COVERED: 5am September 16 - 5am September 17, 2010 (DOY 259/09:00z-260/09:00z)
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
3
3
FGS
REAcq
7
7
OBAD
with Maneuver 3
3
SIGNIFICANT
EVENTS: (None)
OBSERVATIONS
SCHEDULED:
ACS/WFC
12210
SLACS
for the Masses: Extending Strong Lensing to Lower Masses and
Smaller
Radii
Strong
gravitational lensing provides the most accurate possible
measurement
of mass in the central regions of early-type galaxies
(ETGs).
We propose to continue the highly productive Sloan Lens ACS
(SLACS)
Survey for strong gravitational lens galaxies by observing a
substantial
fraction of 135 new ETG gravitational-lens candidates with
HST-ACS
WFC F814W Snapshot imaging. The proposed target sample has been
selected
from the seventh and final data release of the Sloan Digital
Sky
Survey, and is designed to complement the distribution of previously
confirmed
SLACS lenses in lens-galaxy mass and in the ratio of Einstein
radius
to optical half-light radius. The observations we propose will
lead
to a combined SLACS sample covering nearly two decades in mass,
with
dense mapping of enclosed mass as a function of radius out to the
half-light
radius and beyond. With this longer mass baseline, we will
extend
our lensing and dynamical analysis of the mass structure and
scaling
relations of ETGs to galaxies of significantly lower mass, and
directly
test for a transition in structural and dark-matter content
trends
at intermediate galaxy mass. The broader mass coverage will also
enable
us to make a direct connection to the structure of well-studied
nearby
ETGs as deduced from dynamical modeling of their line-of-sight
velocity
distribution fields. Finally, the combined sample will allow a
more
conclusive test of the current SLACS result that the intrinsic
scatter
in ETG mass-density structure is not significantly correlated
with
any other galaxy observables. The final SLACS sample at the
conclusion
of this program will comprise approximately 130 lenses with
known
foreground and background redshifts, and is likely to be the
largest
confirmed sample of strong-lens galaxies for many years to come.
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
11999
JWST
Calibration from a Consistent Absolute Calibration of Spitzer &
Hubble
Recently,
Gordon, Bohlin, et al. submitted a successful Spitzer proposal
for
cross calibration of HST and Spitzer. The cross-calibration targets
are
stars in three categories: WDs, A-stars, and G-stars. Traditionally,
IR
flux standards are extrapolations of stellar models that are tied to
absolute
fluxes at shorter wavelengths. HST absolute flux standards are
among
the best available with a solid basis that uses pure hydrogen
models
of hot WD stars for the SED slopes and is tied to Vega at 5556A
via
precise Landolt V-band photometry. Consistently matching models to
our
three categories of HST observations along with Spitzer photometry
and
the few existing absolute IR flux determinations will provide a
solid
basis for JWST flux calibration over its 0.8-30micron range. The
goal
of this proposal is to complete the HST observations of the set of
HST/Spitzer
cross-calibration stars. Using a variety of standard stars
with
three different spectral types will ensure that the final
calibration
is not significantly affected by systematic uncertainties.
STIS/CCD/MA/S/C
12244
Mapping
Ganymede's Time Variable Aurora in the Search for a Subsurface
Ocean
A
very exciting, unresolved question about Jupiter’s moon Ganymede is
whether
Ganymede harbors a saline subsurface water ocean under its icy
crust.
A saline, electrically conductive water ocean will modify
Ganymede's
magnetic field environment and thus also the locations of
Ganymede's
northern and southern aurora ovals. Without an ocean,
Ganymede's
aurora ovals will rock by ~10 degrees towards and away from
Jupiter
within 5.25 hours. However, with an ocean the shift will be up
to
only ~4 degrees. We propose two visits of five consecutive STIS
orbits
at eastern elongation to monitor and resolve with sufficient
precision
the shift in locations of Ganymede's aurora ovals to
determine
whether an ocean is present on Ganymede. Addressing this
question
is timely as NASA/ESA are planning a Jupiter system mission
including
a Ganymede orbiter with the objective to characterize Ganymede
as
potential habitat.
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/IR
12265
Determining
the Physical Nature of a Unique Giant Lya Emitter at z=6.595
We
propose deep WFC3/IR imaging for a giant Lya emitter (LAE) with a
Keck
spectroscopic redshift of z=6.595 discovered by extensive
narrow-band
imaging with Subaru in the SXDS-UKIDSS/UDS field. This
remarkable
object is unique in many respects including its large stellar
mass
and luminous nebula which extends over 17 kpc; no equivalent source
has
been found in other surveys. The nature of this rare object is
unclear.
Fundamental to progress is determining the origin of star
formation
in such an early massive object; if the age of the stellar
population
is short we are likely witnessing a special moment in the
formation
history of a massive galaxy. The heating source for the nebula
is
also unclear; options include intense star formation, the infall of
cold
gas onto a dark halo or shock heating from a merger. We will take
deep
broad-band (F125W and F160W) images and an intermediate-band
(F098M)
image which will be analyzed in conjunction with ultra-deep IRAC
3.6
and 4.5 micron data being taken by the Spitzer/SEDS project. These
data
will enable us to constrain the star formation rate and stellar
age.
Moreover, the UV continuum morphology and Lya-line distribution
will
be investigated for evidence of a major merger, cold accretion, or
hot
bubbles associated with outflows. We will address the physical
origin
of the remarkable object observed at an epoch where massive
galaxies
are thought to begin their assembly.
WFC3/UV/IR
12234
Differentiation
in the Kuiper belt: a Search for Silicates on Icy
Bodies.
We
currently have a large on-going program (Go Program 11644, 120
orbits)
to exploit the superb stability and photometric characteristics
of
HST and the broad range in wavelength coverage of the WFC3 to make
broad-band
vis/IR spectral observations of a large sample of Kuiper belt
objects.
Though the survey is currently only ~50% complete, the quality
and
unprecedented signal-to-noise of these observations has revealed the
existence
of a previously undiscovered spectral variability not
explainable
within our current understanding of these objects.
A
possible explanation for this variability is that with this faint set
of
Kuiper belt objects, we are beginning to see the difference between
larger
differentiated objects and smaller non-differentiated objects.
Its
seems that the small and likely undifferentiated objects are
exhibiting
silicate features that affect our photometry - features not
exhibited
by the icy mantles of larger icy bodies.
We
propose a small add-on survey to dramatically increase the scientific
results
of our large program. The proposed observations will use the
proven
capabilities of WFC3 to make broad and narrow-band photometric
observations
to detect spectral features in the 1.0-1.3 micron range of
a
small subset of our sources. The 13 targets have been carefully
selected
to cover the range of spectral variability detected in our
large
program as well as sample the entire dynamical range and physical
sizes
of these targets. These observations will allow the identification
of
undifferentiated Kuiper belt objects by detection of their silicate
features.
As a probe for differentiation, these observations could
constrain
the natal locations of different Kuiper belt classes, a
constraint
currently unavailable to formation models. This small set of
observations
will allow the calibration of the spectral variability seen
in
our large program, and drastically enhance the scientific output of
our
full Cycle 17 sample.
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
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.
-Lynn HST
AOD Mission Success: "There is only DO...no try. "*
Lynn F.
Bassford office#: 301-286-2876
Hubble Space Telescope
CHAMP Mission Operations Manager
CHAMP Flight Operations Team Manager
Lockheed Martin Mission Services (LMMS)