HUBBLE SPACE TELESCOPE - Continuing to collect World
Class Science
DAILY REPORT #4887
PERIOD COVERED: 5am July 14 - 5am July 15, 2009 (DOY
195/0900z-196/0900z)
OBSERVATIONS SCHEDULED
ACS 11465
ACS CCD monitoring and calibration for WFC
This program is a smaller version of our routine CCD
monitoring program,
designed to run throughout SMOV, after which our regular
Cycle 17 CAL
proposal will begin. This program obtains the bias and dark
frames
needed to generate reference files for calibrating science data,
and
allows us to monitor detector noise and the growth of hot pixels.
COS 11492
FUV Sensitivity
DESCRIPTION: This activity confirms COS sensitivity
versus wavelength
over the entire observable spectrum for all FUV gratings
and central
wavelength settings. Obtain quicklook sensitivity visit early in
SMOV.
Later, after wavelength calibration is verified, perform
a
precise-centering acquisition and observe an appropriate HST
flux
standard star (chosen from the HST prime standard and FASTEX lists)
with
the PSA. (A limited BOA characterization is obtained in Visit 13
using
primary standard GD153.) No off aperture-center observations
are
performed in this activity (see COS32, program 11490, for
off-center
characterizations). Spectra will be obtained to meet a Poisson
S/N
criterion of ~30 per sensitivity extraction bin or higher;
substantially
higher S/N characterization will be utilized in routine Cycle
17
calibration.
COS05 11466
NUV Detector Dark
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.
FGS 11212
Filling the Period Gap for Massive Binaries
The current census of binaries among the massive O-type
stars is
seriously incomplete for systems in the period range from years
to
millennia because the radial velocity variations are too small and
the
angular separations too close for easy detection. Here we propose
to
discover binaries in this observational gap through a Faint
Guidance
Sensor SNAP survey of relatively bright targets listed in the
Galactic O
Star Catalog. Our primary goal is to determine the binary
frequency
among those in the cluster/association, field, and runaway groups.
The
results will help us assess the role of binaries in massive
star
formation and in the processes that lead to the ejection of
massive
stars from their natal clusters. The program will also lead to
the
identification of new, close binaries that will be targets of long
term
spectroscopic and high angular resolution observations to
determine
their masses and distances. The results will also be important for
the
interpretation of the spectra of suspected and newly identified
binary
and multiple systems.
WFC3 11426
UVIS SMOV Contamination Monitor
The UV throughput of WFC3 during SMOV is monitored via
weekly standard
star observations in a subset of key filters (as many as will
fit into a
single orbit but to include at a minimum F218W, F225W, F275W,
and
F606W). The data will provide a measure of throughput levels as
a
function of time and wavelength, allowing for detection of the
presence
of possible contaminants. In addition, a small set of internal
exposures
are included with the externals, to provide verification of
detector
stability.
This proposal corresponds to activity WFC3-13.
WFC3 11427
UVIS Shutter Test
This test will provide calibration data to characterize
the performance
of the WFC3 UVIS shutter. Images with exposure times ranging
from 0.5 to
17 seconds will be used to quantify shutter shading, accuracy,
and
stability.
WFC3 11432
UVIS Internal Flats
This proposal will be used to assess the stability of
the flat field
structure for the UVIS detector. Flat fields will be obtained
for all
filters using the internal D2 and Tungsten lamps.
This proposal corresponds to Activity Description ID
WF19. It should
execute only after the following proposals have executed:
WF08 - 11421
WF09 - 11422 WF11 - 11424 WF15 - 11428
WFC3 11433
IR Internal Flat Fields
This proposal corresponds to WFC3-20, and depends on the
completion of
the IR initial alignment (proposal 11425, WFC3-12). In this
test, we
will study the stability and structure of the IR channel flat
field
images through all filter elements in the WFC3-IR channel. Flat
field
images for each filter will be combined in order to produce
a
calibration-quality flat field image. High signal observations
will
provide a map of the pixel-to-pixel flat field structure, as well
as
identify the positions of any dust particles.
WFC3 11450
UVIS Photometric Zero Points
This proposal obtains the photometric zero points in 16
WFC3/UVIS
priority-1 filters, 20 WFC3/UVIS priority-2 filters, and 1
WFC3/UVIS ERO
filter using a hot DA white dwarf. The observations are
repeated at
intervals of 1 day, 7 days, and 30 days, to monitor
photometric
stability in 8 of the priority-1 filters, with emphasis in the UV
where
contamination would have the strongest effects.
WFC3 11451
IR Photometric Zero Points
This proposal obtains the photometric zero points in all
15 WFC3/IR
filters using two stars with distinct temperatures (a hot DA white
dwarf
and a solar analog). The observations are repeated at intervals of
1
day, 7 days, and 30 days, to monitor photometric stability in
all
filters.
WFC3 11808
WFC3 UVIS Bowtie Monitor
The UVIS detector was observed during ground testing to
occasionally
exhibit flat field and dark variations with a bowtie pattern.
These
variations are most significant as ~1% flat field (gain)
variations
across the field of view. It is believed that this represents a
state or
condition into which the detector can transition for reasons and
under
circumstances which are not currently understood. It is also
very
unlikely that most science observations will determine the state
(bowtie
or no-bowtie) of the detector. Ground test data indicates that
this
state is long lived (many hours to ~one day). Hysteresis or memory
of
past light exposure is also associated with this state.
Recent evidence suggests that exposing the detector to
~200k to 500k
electrons may quench this state. This proposal obtains an
internal flat
field sequence of three exposures: one at 10x full well with
two at 0.5x
full well immediately before and after. Each exposure is 3x3
binned to
reduce the data volume required.
These visits should be scheduled 2x per day until
further direction is
provided.
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
08
08
FGS REAcq
10
10
OBAD with Maneuver
04
04
SIGNIFICANT EVENTS: (None)