HUBBLE
SPACE TELESCOPE - Continuing to Collect World Class Science
DAILY
REPORT #4955
PERIOD
COVERED: 5am October 20 - 5am October 21, 2009 (DOY293/09:00z-294/09:00z)
OBSERVATIONS
SCHEDULED
FGS
11785
Trigonometric
Calibration of the Distance Scale for Classical Novae
The
distance scale for classical novae is important for understanding
the
stellar physics of their thermonuclear runaways, their contribution
to
Galactic nucleosynthesis, and their use as extragalactic standard
candles.
Although it is known that there is a relationship between their
absolute
magnitudes at maximum light and their subsequent rates of
decline--the
well-known maximum-magnitude rate-of-decline (MMRD)
relation--it
is difficult to set the zero-point for the MMRD because of
the
very uncertain distances of Galactic novae.
We
propose to measure precise trigonometric parallaxes for the quiescent
remnants
of the four nearest classical novae. We will use the Fine
Guidance
Sensors, which are proven to be capable of measuring parallaxes
with
errors of ~0.2 mas, well below what is possible from the ground.
NIC
11417
NICMOS
Detector Read noise and Dark Current
The
NICMOS detector characteristics will be monitored during the entire
extent
of the SMOV4 through a set of dark exposures. This will also
allow
a determination of the detector temperature from bias
measurements.
The data should be obtained in SAA-free orbits,
approximately
every 24 hours. In addition, the detector read noise and
the
detector shading profiles will be measured once a week.
NIC1/NIC2/NIC3
11820
NICMOS
Post-SAA Calibration - CR Persistence Part 7
Internals
for CR persistence
NIC2
11148
High
Contrast Imaging of Dusty White Dwarfs
For
the past 18 years, only one white dwarf with a circumstellar dust
disk
was known to exist. In the last two years, six new disks have been
discovered.
Since all material inwards of a few AU should be scoured
clean
during post main sequence evolution, the primary explanation is
the
presence of a planetary system that is perturbing relic
planetesimals
into the tidal disruption radius of the white dwarf. Dusty
disks
around white dwarfs should be markers for planets and we propose
to
use high contrast imaging to search for faint companions down to 6
M_$J$
that may be feeding the disks. White dwarfs are uniquely suited
for
planet searches, where the planet/white dwarf contrast is less than
for
main sequence 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/MA1/MA2
11857
STIS
Cycle 17 MAMA Dark Monitor
This
proposal monitors the behavior of the dark current in each of the
MAMA
detectors.
The
basic monitor takes two 1380s ACCUM darks each week with each
detector.
However, starting Oct 5, pairs are only included for weeks
that
the LRP has external MAMA observations planned. The weekly pairs of
exposures
for each detector are linked so that they are taken at
opposite
ends of the same SAA free interval. This pairing of exposures
will
make it easier to separate long and short term temporal variability
from
temperature dependent changes.
For
both detectors, additional blocks of exposures are taken once every
six
months. These are groups of five 1314s FUV-MAMA Time-Tag darks or
five
3x315s NUV ACCUM darks distributed over a single SAA-free interval.
This
will give more information on the brightness of the FUV MAMA dark
current
as a function of the amount of time that the HV has been on, and
for
the NUV MAMA will give a better measure of the short term
temperature
dependence.
WFC3/ACS/UVIS
11360
Star
Formation in Nearby Galaxies
Star
formation is a fundamental astrophysical process; it controls
phenomena
ranging from the evolution of galaxies and nucleosynthesis to
the
origins of planetary systems and abodes for life. The WFC3,
optimized
at both UV and IR wavelengths and equipped with an extensive
array
of narrow-band filters, brings unique capabilities to this area of
study.
The WFC3 Scientific Oversight Committee (SOC) proposes an
integrated
program on star formation in the nearby universe which will
fully
exploit these new abilities. Our targets range from the
well-resolved
R136 in 30 Dor in the LMC (the nearest super star cluster)
and
M82 (the nearest starbursting galaxy) to about half a dozen other
nearby
galaxies that sample a wide range of star-formation rates and
environments.
Our program consists of broad band multiwavelength imaging
over
the entire range from the UV to the near-IR, aimed at studying the
ages
and metallicities of stellar populations, revealing young stars
that
are still hidden by dust at optical wavelengths, and showing the
integrated
properties of star clusters. Narrow-band imaging of the same
environments
will allow us to measure star-formation rates, gas
pressure,
chemical abundances, extinction, and shock morphologies. The
primary
scientific issues to be addressed are: (1) What triggers star
formation?
(2) How do the properties of star-forming regions vary among
different
types of galaxies and environments of different gas densities
and
compositions? (3) How do these different environments affect the
history
of star formation? (4) Is the stellar initial mass function
universal
or determined by local conditions?
WFC3/IR
11108
Near
Infrared Observations of a Sample of z~6.5-6.7 Galaxies
The
majority of the most distant galaxies discovered to date have been
found
by strong Lyman alpha emission at red optical wavelengths. An
accurate
estimate of the star formation rates for these objects requires
a
measurement of the line-free UV continuum, which must be taken at
infrared
wavelengths. Here we propose to obtain imaging with WFC3 in the
F140W
filter for a sample of 9 Lyman alpha galaxies with redshifts z~6.5
up
to z=6.740 from a complete, flux- limited widefield narrowband and
multi-color
survey conducted on the 8-m Subaru Telescope. This program
will
investigate galaxy morphologies and star formation for a uniform
sample
of the highest redshift galaxies now known.
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/ACS/WFC
11688
Exploring
the Bottom End of the White Dwarf Cooling Sequence in the Open
Cluster
NGC6819
The
recent discovery by our group of an unexpectedly bright end of the
white-dwarf
(WD) luminosity function (LF) of the metal-rich, old open
cluster
NGC 6791 casts serious doubts on our understanding of the
physical
process which rules the formation and the cooling of WDs. It is
clear
at this point that the theory badly needs more observations. Here
we
propose WFC3/UVIS and ACS/WFC HST observations reaching the bottom
end
of the WD LF, for the first time in a solar-metallicity,
2.5-Gyr-old,
populous open cluster: NGC 6819.
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
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.
WFC3/UVIS
11925
UVIS
Detector Linearity
This
proposal will measure the in-orbit linear response of the UVIS
detectors
by sampling over the response curve through saturation. This
program
uses exposures of a standard star field (NGC 1850) to measure
the
absolute values, and exposures of a tungsten lamp to measure
positional
variations in response, following a similar procedure as the
ground
tests.
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
11
11
FGS
REAcq
07
07
OBAD
with Maneuver
07
07
SIGNIFICANT
EVENTS: (None)