HUBBLE SPACE TELESCOPE - Continuing to collect World Class
Science
DAILY REPORT #4797
PERIOD COVERED: 5am February 23 - 5am February 24, 2009
(DOY
054/1000z-055/1000z)
OBSERVATIONS SCHEDULED
WFPC2 11302
WFPC2 CYCLE 16 Standard Darks - Part III
This dark calibration program obtains dark frames every
week in order to
provide data for the ongoing calibration of the CCD dark
current rate,
and to monitor and characterize the evolution of hot
pixels. Over an
extended period these data will also provide a monitor of
radiation
damage to the CCDs.
WFPC2 11316
HST Cycle 16 & Pre-SM4 Optical Monitor
This is a continuation of the Cycle 15 & pre-SM4
Optical Monitor, 11020.
Please see that proposal for a more complete description
of the
observing strategy. The 6 visits comprising this proposal
observe two
single standard stars with WFPC2/PC in order to establish
overall OTA
focal length for the purposes of focus maintenance. The
goal of this
monitoring before SM4 is to establish a best estimate of
the OTA focus
entering SMOV.
WFPC2 11603
A Comprehensive Study of Dust Formation in Type II
Supernovae with HST,
Spitzer and Gemini
The recent discovery of three extremely bright Type II
SNe, (2007it,
2007oc, 2007od) gives us a unique opportunity to combine
observations
with HST, Spitzer and Gemini to study the little
understood dust
formation process in Type II SNe. Priority 1 Spitzer Cycle
5 and band 1
Gemini 2008A time has already been approved for this
project. Since
late-time Type II SNe are faint and tend to be in crowded
fields, we
need the high sensitivity and high spatial resolution of
ACS/HRC and
NICMOS/NIC2 for these observations. This project is
motivated by the
recent detection of large amounts of dust in high redshift
galaxies. The
dust in these high-z galaxies must come from young,
massive stars so
Type II SNe could be potential sources. The mechanism and
the efficiency
of dust condensation in Type II SN ejecta are not well
understood,
largely due to the lack of observational data. We plan to
produce a
unique dataset, combining spectroscopy and imaging in the
visible, near-
and mid-IR covering the key phase, 400-700 days after
maximum when dust
is known to form in the SN ejecta. Therefore, we are
proposing for
coordinated HST/NOAO observations (HST ACS/HRC,
NICMOS/NIC2 &
Gemini/GMOS and TReCS) which will be combined with our
Spitzer Cycle 5
data to study these new bright SNe. The results of this
program will
place strong constraints on the formation of dust seen in
young high
redshift (z>5) galaxies.
WFPC2 11793
WFPC2 Cycle 16 Internal Monitor
This calibration proposal is the Cycle 15 routine internal
monitor for
WFPC2, to be run weekly to monitor the health of the
cameras. A variety
of internal exposures are obtained in order to provide a
monitor of the
integrity of the CCD camera electronics in both bays (both
gain 7 and
gain 15 -- to test stability of gains and bias levels), a
test for
quantum efficiency in the CCDs, and a monitor for possible
buildup of
contaminants on the CCD windows. These also provide raw
data for
generating annual super-bias reference files for the
calibration
pipeline.
WFPC2 11956
Hubble Heritage: Side B
We propose a program of 39 orbits to observe 6 targets
with WFPC2
following a successful return to science using side B
electronics. These
observations will be used for Hubble Heritage releases in
the months
leading up to servicing mission 4. Because of launch
delays, our reserve
of releasable images is growing dangerously slim. We are
proposing here
to replenish one of our important lines of communication
with the
public.
We have carefully chosen targets that can efficiently use
single
pointings of WFPC2 to obtain images of visually striking
and
astrophysically interesting targets. Observations will
reach high S/N
and will be dithered and subsampled to improve the
resolution and pixel
scale to near ACS/WFC3 quality at a modest cost in
exposure time. Most
of the observations will schedule in the interim between a
return to
science and the availability of new science proposals that
may be
selected in response to an interim call for proposals.
WFPC2 11974
High-resolution Imaging for 9 Very Bright, Spectroscopically
Confirmed,
Group-scale Lenses
There are large samples of strong lenses that probe small
(galaxy) scale
masses (e.g., SLACS, SQLS, COSMOS). There are also large
samples of
strong lenses that probe large (rich cluster) scale masses
(e.g.,
various rich Abell clusters, the Hennawi et al. 2008 SDSS
sample). The
sample of strong lenses that probe intermediate
(group/cluster-core)
scale masses, however, is sparse, and so any significant
additions to
this sample are important. Here we present a sample of
strong lenses
that not only probe these intermediate scales but are also
quite bright,
since the sample is based almost entirely upon data from
the SDSS, a
relatively shallow and poor-resolution survey, at least in
comparison to
most other strong lens hunting grounds, such as COSMOS and
CFHTLS. What
we lack are the high-resolution imaging data needed to
construct
detailed lensing models, to probe the mass and light
profiles of the
lensing galaxies and their environments, and to
characterize the
morphologies of the lensed (source) galaxies. Only HST can
provide these
data, and so we are proposing here for 81 orbits of deep
WFPC2 F450W,
F606W and F814W imaging, for 9 of our best and brightest
intermediate-scale lensing systems with known
spectroscopic redshifts
and with Einstein radii between 4 and 8 arcsec.
WFPC2 11986
Completing HST's Local Volume Legacy
Nearby galaxies offer one of the few laboratories within
which stellar
populations can be tied to multi-wavelength observations.
They are thus
essential for calibrating and interpreting key
astrophysical
observables, such as broad-band luminosities, durations
and energy input
from starbursts, and timescales of UV, H-alpha, and FIR
emission. The
study of stellar populations in nearby galaxies requires
high-resolution
observations with HST, but HST's legacy for this limited
set of galaxies
remains incomplete.
As a first attempt to establish this legacy, The ACS
Nearby Galaxy
Survey Treasury (ANGST) began observations in late 2006.
ANGST was
designed to carry out a uniform multi-color survey of a
volume-limited
sample of ~70 nearby galaxies that could be used for
systematic studies
of resolved stellar populations. The resulting data
provide nuanced
constraints on the processes which govern star formation
and galaxy
evolution, for a well-defined population of galaxies. All
photometry for
the survey has been publicly released.
However, the failure of ACS 4.5 months after ANGST began
taking data led
to a drastic reduction in the planned survey. The loss is
two-fold.
First, the goals of completeness and uniformity were
greatly
compromised, impacting global comparison studies. Second,
the variety of
observed star formation histories was reduced. Given that
we have never
found two galaxies with identical star formation
histories, and fully
sampling the population allows us to catch those few
systems whose star
formation rates and metallicities place the strongest
constraints on key
astrophysical processes.
Here we propose WFPC2 observations of all remaining
galaxies within the
Local Volume (D<3.5Mpc) for which current HST
observations are
insufficient for meaningful stellar population studies. We
will use
these observations for research on the star formation
histories of
individual galaxies and the Local Volume, detailed
calibrations of star
formation rate indicators, and the durations of
starbursts. We will also
make them publicly available through the ANGST archive to
support future
research. The proposed observations will finally complete
a lasting
legacy of HST
FLIGHT OPERATIONS SUMMARY:
Significant Spacecraft Anomalies: (The following are
preliminary reports
of potential non-nominal performance that will be
investigated.)
HSTARS:
11696 - REAcq (1,0,1) scheduled at 054/10:30:59 failed to
RGA control at
10:34:50. Stop flags QF1STOPF and QSTOP were received for FGS 1.
REAcq (1,0,1)
at 054/12:06:52z was successful.
Observations affected: WFPC 18 – 29, Proposal ID# 11793.
11697 - GSAcq (1,2,2) scheduled from 054/13:46:40 -
13:53:54 failed to RGA Hold
due to QF1STOPF and QSTOP flags on FGS-1.
Observations affected: WFPC 31 - 32, Proposal ID# 11956.
11698 - GSAcq (1,2,2) at 054/22:03:29 failed to RGA
control at 22:07:28
with QF1STOPF and QSTOP flags set.
REAcq (1,2,2) at 054/23:27:42 also failed at 23:31:20.
REAcq (1,2,2) at 055/01:03:36 was successful.
Observations affected: WFPC 62 to 72, Proposal ID# 11603.
COMPLETED OPS REQUEST: (None)
COMPLETED OPS NOTES: (None)
SCHEDULED
SUCCESSFUL
FGS
GSacq
06
04
FGS
REacq
09
07
OBAD with Maneuver
30
30
SIGNIFICANT EVENTS: (None)