HUBBLE
SPACE TELESCOPE - Continuing to Collect World Class Science
DAILY
REPORT #5022
PERIOD
COVERED: 5am January 28 - 5am January 29, 2010 (DOY 028/10:00z-029/10:00z)
OBSERVATIONS
SCHEDULED
COS/FUV
11897
FUV
Spectroscopic Sensitivity Monitoring
The
purpose of this proposal is to monitor sensitivity in each FUV
grating
mode to detect any changes due to contamination or other causes.
STIS/CC/MA
11608
How
Far Does H2 Go: Constraining FUV Variability in the Gaseous Inner
Holes
of Protoplanetary Disks
By
studying the innermost, planet-forming regions of circumstellar disks
around
low-mass pre-main sequence stars we can refine theories of planet
formation
and develop timescales for the evolution of disks and their
planets.
Spitzer infrared observations of T Tauri stars have given us an
unprecedented
look at dust evolution in young objects, particularly the
transitional
disks. However, despite this ground breaking progress in
studying
the dust in young disks, the relationship between the dust and
gas
properties in the inner disk remains essentially unknown. Using STIS
on
HST, we propose to quantify the variability of H2 emission
originating
within the inner holes of transitional disks and explore its
implications
on dust distribution and planet formation.
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/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/ACS/IR
11677
Is
47 Tuc Young? Measuring its White Dwarf Cooling Age and Completing a
Hubble
Legacy
With
this proposal we will firmly establish the age of 47 Tuc from its
cooling
white dwarfs. 47 Tuc is the nearest and least reddened of the
metal-rich
disk globular clusters. It is also the template used for
studying
the giant branches of nearby resolved galaxies. In addition,
the
age sensitive magnitude spread between the main sequence turnoff and
horizontal
branch is identical for 47 Tuc, two bulge globular clusters
and
the bulge field population. A precise relative age constraint for 47
Tuc,
compared to the halo clusters M4 and NGC 6397, both of which we
recently
dated via white dwarf cooling, would therefore constrain when
the
bulge formed relative to the old halo globular clusters. Of
particular
interest is that with the higher quality ACS data on NGC
6397,
we are now capable with the technique of white dwarf cooling of
determining
ages to an accuracy of +/-0.4 Gyrs at the 95% confidence
level.
Ages derived from the cluster turnoff are not currently capable
of
reaching this precision. The important role that 47 Tuc plays in
galaxy
formation studies, and as the metal-rich template for the
globular
clusters, makes the case for a white dwarf cooling age for this
metal-rich
cluster compelling.
Several
recent analyses have suggested that 47 Tuc is more than 2 Gyrs
younger
than the Galactic halo. Others have suggested an age similar to
that
of the most metal poor globular clusters. The current situation is
clearly
uncertain and obviously a new approach to age dating this
important
cluster is required.
With
the observations of 47 Tuc, this project will complete a legacy for
HST.
It will be the third globular cluster observed for white dwarf
cooling;
the three covering almost the full metallicity range of the
cluster
system. Unless JWST has its proposed bluer filters (700 and 900
nm)
this science will not be possible perhaps for decades until a large
optical
telescope is again in space. Ages for globular clusters from the
main
sequence turnoff are less precise than those from white dwarf
cooling
making the science with the current proposal truly urgent.
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/UV
11640
Lyman
Alpha Imaging of Two Quasar Host Galaxies at z>6
We
propose to image the Lyman Alpha emission line in two of the highest
redshift
quasar host galaxies (redshifts z=6.31 and 6.42) to map the
amount
and extent of star formation in the hosts and in their immediate
environment.
These observations are now possible for the first time, as
UVIS
on WFC3 (coincidentally) provides narrow-band filters at the right
wavelengths.
Circumstantial evidence (based on NIR, radio/millimeter and
molecular
gas measurements) suggests that these quasar hosts are
undergoing
intense ~1000 Msun/yr bursts of star formation over scales of
~5kpc
(0.6"). Our program will provide (continuum-subtracted) images of
the
Lyman Alpha emission in the host which will in turn directly
constrain
the extent and magnitude of star formation in the host. In the
case
of the host galaxy of J1148+5251 (z=6.42) the Lyman Alpha emission
will
be compared to resolved imaging of the molecular gas phase (CO and
[CII])
which in turn will yield critical constraints on the structure of
the
host galaxy and the conditions of the interstellar medium. The
observations
should also be sensitive enough to reveal potential
companion
galaxies (if the quasars are residing in major overdensities
at
these redshifts) and infall signatures in the immediate vicinity of
the
quasar. The narrow-band filters of UVIS/WFC3 provide the unique
opportunity
to study host/bulge formation at the end of cosmic
reionization
(less than 1Gyr after the Big Bang).
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
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 existing 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/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
11908
Cycle
17: UVIS Bowtie Monitor
Ground
testing revealed an intermittent hysteresis type effect in the
UVIS
detector (both CCDs) at the level of ~1%, lasting hours to days.
Initially
found via an unexpected bowtie-shaped feature in flatfield
ratios,
subsequent lab tests on similar e2v devices have since shown
that
it is also present as simply an overall offset across the entire
CCD,
i.e., a QE offset without any discernable pattern. These lab tests
have
further revealed that overexposing the detector to count levels
several
times full well fills the traps and effectively neutralizes the
bowtie.
Each visit in this proposal acquires a set of three 3x3 binned
internal
flatfields: the first unsaturated image will be used to detect
any
bowtie, the second, highly exposed image will neutralize the bowtie
if
it is present, and the final image will allow for verification that
the
bowtie is gone.
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:
18808-0
- Null genslews for proposal 12053 - Slots 2 and 3 @ 028/1836z
COMPLETED
OPS NOTES: (None)
SCHEDULED
SUCCESSFUL
FGS
GSAcq
9
9
FGS
REAcq
7
7
OBAD
with Maneuver 6
6
SIGNIFICANT
EVENTS: (None)