HUBBLE
SPACE TELESCOPE - Continuing to Collect World Class Science
DAILY
REPORT #4937
PERIOD
COVERED: 5am September 23 - 5am September 24, 2009 (DOY 266/09:00z-267/09:00z)
OBSERVATIONS
SCHEDULED
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/NUV
11466
NUV
Detector Dark
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 data in order to verify the nominal operation of the
detector,
and for use in the CalCOS calibration pipeline. Variations of
count
rate as a function of orbital position will be analyzed to find
dependence
of dark rate on proximity to the SAA.
COS/NUV
11899
NUV
Imaging Sensitivity, Cycle 17
The
purpose of this proposal is to test NUV imaging sensitivity for a
range
of target spectral energy distributions. All targets have
wide-slit
STIS spectra in the HST Archive. We use eleven horizontal
branch
stars in the globular cluster NGC 6681 covering a range of
effective
temperatures, plus a solar-analog standard star.
COS/NUV
11900
NUV
Internal/External Wavelength Scale Monitor
This
program monitors the offsets between the wavelength scale set by
the
internal wavecal versus that defined by absorption lines in external
targets.
This is accomplished by observing two external radial velocity
standard
targets: HD187691 with G225M and G285M and HD6655 with G285M
and
G230L. The two standard targets have little flux in the wavelength
range
covered by G185M and so Feige 48 (sdO) is observed with this
grating.
Both Feige 48 and HD6655 are also observed in SMOV. The
cenwaves
observed in this program are a subset of the ones used during
Cycle
17. Observing all cenwaves would require a considerably larger
number
of orbits. Constraints on scheduling of each target are placed so
that
each target is observed once every ~2-3 months. Observing the three
targets
every month would also require a considerably larger number of
orbits.
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.
NIC1/NIC2/NIC3
8795
NICMOS
Post-SAA Calibration - CR Persistence Part 6
This
is 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 'Use After' 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 darks. 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.
STIS/CCD
11567
Boron
Abundances in Rapidly Rotating Early-B Stars
Models
of rotation in early-B stars predict that rotationally driven
mixing
should deplete surface boron abundances during the main-sequence
lifetime
of many stars. However, recent work has shown that many boron
depleted
stars are intrinsically slow rotators for which models predict
no
depletion should have occurred, while observations of nitrogen in
some
more rapidly rotating stars show less mixing than the models
predict.
Boron can provide unique information on the earliest stages of
mixing
in B stars, but previous surveys have been biased towards
narrow-lined
stars because of the difficulty in measuring boron
abundances
in rapidly rotating stars. The two targets observed as part
of
our Cycle 13 SNAP program 10175, just before STIS failed, demonstrate
that
it is possible to make useful boron abundance measurements for
early-B
stars with Vsin(i) above 100 km/s. We propose to extend that
survey
to a large enough sample of stars to allow statistically
significant
tests of models of rotational mixing in early-B stars.
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/MA1
12010
COS
FUV Line Spread Function Characterization
In
this program we will observe the star Sk-155 (an O9b star in the SMC)
with
the high resolution E140H grating on STIS. Sk-155 was observed with
COS
during SMOV with the purpose of confirming the spectroscopic
resolution
of the FUV medium resolution gratings (G130M and G160M).
Comparison
of the E140H spectra with the COS spectra shows that the COS
spectral
resolution is likely significantly impacted by broad non-
Gaussian
wings in the COS LSF. Further tests and characterization of
this
effect is critical for evaluating the final spectroscopic
resolution
of COS. However, the existing STIS/E140H spectra of Sk-155
only
cover the wavelength range 1165-1350 A (good for testing the G130M
spectral
resolution). They do not extend to long enough wavelenghts to
test
the COS G160M spectral resolution. Therefore, in this supplemental
STIS
program we will use 2 HST orbits to re-observe Sk 155 with STIS. We
will
utilize the E140H grating with the 0.2x0.09 aperture and central
wavelength
of 1598 angstroms which covers the missing wavelength range
1500-1700
angstroms.
WFC3/ACS/IR
11359
Panchromatic
WFC3 Survey of Galaxies at Intermediate z: Early Release
Science
Program for Wide Field Camera 3
The
unique panchromatic capabilities of WFC3 will be used to survey the
structure
and evolution of galaxies at the peak of the galaxy assembly
epoch.
Deep ultraviolet and near-IR imaging and slitless spectroscopy of
existing
deep multi-color ACS fields will be used to gauge
star-formation
and the growth of stellar mass as a function of
morphology,
structure and surrounding density in the critical epoch 1 <
z
< 4. Images in the F225W, F275W, and F336W filters will identify
galaxies
at z < 1.5 from their UV continuum breaks, and provide
star-formation
indicators tied directly to both local and z > 3
populations.
Deep near-IR (F125W and F160W) images will probe the
stellar
mass function well below 10^9 Msun for mass-complete samples.
Lastly,
the WFC3 slitless UV and near-IR grisms will be used to measure
redshifts
and star-formation rates from H- alpha and rest-frame UV
continuum
slope. This WFC3 ERS program will survey one 4 x 2 mosaic for
a
total area of 50 square arcminutes to 5-sigma depths of m_AB = 27 in
most
filters from the mid-UV through the near-IR.
This
multicolor high spatial resolution data set will allow the user to
gauge
the growth of galaxies through star-formation and merging. High
precision
photometric and low- resolution spectroscopic redshifts will
allow
accurate determinations of the faint-end of the luminosity and
mass
functions, and will shed light on merging and tidal disruption of
stellar
and gaseous disks. The WFC3 images will also allow detailed
studies
of the internal structure of galaxies, and the distribution of
young
and old stellar populations. This program will demonstrate the
unique
power of WFC3 by applying its many diverse modes and full
panchromatic
capability to a forefront problem in astrophysics.
WFC3/ACS/IR
11600
Star
Formation, Extinction, and Metallicity at 0.7<z<1.5: H-Alpha Fluxes
and
Sizes from a Grism Survey of GOODS-N
The
global star formation rate (SFR) is ~10x higher at z=1 than today.
This
could be due to drastically elevated SFR in some fraction of
galaxies,
such as mergers with central bursts, or a higher SFR across
the
board. Either means that the conditions in z=1 star forming galaxies
could
be quite different from local objects. The next step beyond
measuring
the global SFR is to determine the dependence of SFR,
obscuration,
metallicity, and size of the star-forming region on galaxy
mass
and redshift. However, SFR indicators at z=1 typically apply local
calibrations
for UV, [O II] and far-IR, and do not agree with each other
on
a galaxy-by-galaxy basis. Extinction, metallicity, and dust
properties
cause uncontrolled offsets in SFR calibrations. The great
missing
link is Balmer H-alpha, the most sensitive probe of SFR. We
propose
a slitless WFC3/G141 IR grism survey of GOODS-N, at 2
orbits/pointing.
It will detect Ha+[N II] emission from 0.7<z<1.5, to
L(Ha)
= 1.7 x 10^41 erg/sec at z=1, measuring H-alpha fluxes and sizes
for
> 600 galaxies, and a small number of higher-redshift emitters. This
will
produce: an emission-line redshift survey unbiased by magnitude and
color
selection; star formation rates as a function of galaxy
properties,
e.g. stellar mass and morphology/mergers measured by ACS;
comparisons
of SFRs from H-alpha to UV and far-IR indicators;
calibrations
of line ratios of H-alpha to important nebular lines such
as
[O II] and H-beta, measuring variations in metallicity and extinction
and
their effect on SFR estimates; and the first measurement of scale
lengths
of the H-alpha emitting, star-forming region in a large sample
of
z~1 sources.
WFC3/IR/S/C
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/UVIS
11559
Jovian
Upheaval and Its Impact on Vortices
We
propose observations of Jupiter with global coverage at high
resolution
to quantify changes in its atmosphere during and following
the
global upheaval. Only HST has the capability to obtain images with
enough
spatial resolution and contrast to extract velocity fields (we
will
use our newly developed technique to accomplish this), and with
WFC3
we can image Jupiter in its entirety in a single exposure. We are
in
particular interested in the Red Oval BA: Will the Oval be long
lived,
remain red, or turn white again, disappear? Both the merger of
its
precursors, and change in color has never before been witnessed. The
Great
Red Spot: This storm system appears to decrease in size and has
become
rounder, both as derived from its associated cloud deck, but also
from
its potential vorticity, a more dynamically-relevant quantity. How
will
the GRS evolve? Will it swallow the new vortices detected in
amateur
images at this same latitude band? How will this effect the
potential
vorticity? In addition, we hope to understand disturbances and
stagnation
points, both of which were detected during the present global
upheaval:
are these cyclonic regions, can they spawn anticyclones (as
suggested
by amateur images)?
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
6
6
FGS
REAcq
8
8
OBAD
with Maneuver
6
6
SIGNIFICANT
EVENTS: (None)