Status Report

NASA Hubble Space Telescope Daily Report # 3438 (part 2)

By SpaceRef Editor
September 3, 2003
Filed under , ,


Spectroscopy and Polarimetry of Mars at Closest Approach

We plan a coordinated program of spectroscopy, imaging, and
spectropolarimetry of Mars during the August 2003 opposition to study
the composition and physical state of surface materials and airborne
aerosols. The observations include {a} Moderate spectral resolution
290 to 570 nm STIS long-slit push-broom imaging spectroscopy of Mars,
to constrain the properties of airborne aerosol particles and to
search for and globally map iron-bearing minerals that are diagnostic
of specific past climatic conditions; {b} WFPC2 UV-VIS images designed
primarily to quantify the effects of ice and dust aerosols on our STIS
spectra; {c} NICMOS near-IR images to search for and globally map the
presence of hydrated surface minerals; and {d} ACS multispectral
polarizer images to provide critical phase function measurements
needed to constrain the physical properties of the Martian surface
layer. The observations are timed to take advantage of the closest
approach of Mars to Earth for the next several hundred years. Images
and spectra will be acquired at a spatial scale comparable to existing
spacecraft orbital spectroscopy data {~10 km/pixel} and in wavelength
regions not sampled by past or current Mars spacecraft
instrumentation. These observations also provide complementary
scientific and calibration measurements in support of current and
future NASA and ESA Mars exploration missions.


Kepler’s Supernova Remnant: an Imaging Study of the Blast Wave –
Circumstellar Medium Interaction

Kepler’s SNR {SN 1604 AD} is the prime example of a young Galactic SNR
where the blast wave is running into the wind of the progenitor star.
The interaction between the blast wave and the inhomogeneous
circumstellar medium gives rise to knots, evolving on a time scale of
years, that dominate the optical emission from the remnant. Also
visible in the optical are fainter Balmer line filaments that exhibit
a range of geometries – from normal sheet-like filaments to more
diffuse clumps of emission, the latter unique to this remnant. We
propose to image Kepler’s SNR through several narrowband filters using
ACS/WFC and WFPC2. The morphology and ionization structure of the
knots will be obtained from H-alpha, [S II], and [O III] images. We
will also obtain a [N II] image, which is known to be strong and
spatially variable in the remnant. The proposed H-alpha images will be
deep enough so that the physical scales and structure of the Balmer
dominated non-radiative shocks can be investigated. Our data will be a
critical part of multiwavelength studies of Kepler’s SNR. They will
complement Chandra and XMM X-ray data and VLA radio data, and provide
a significant advance in understanding the processes of magnetic field
amplification and cosmic ray acceleration in SNRs as well as the
evolution and dynamics of the blast wave – circumstellar medium

NIC2 9726

A NICMOS search for obscured supernovae in starburst galaxies

Recent near-IR monitoring campaigns were successful in detecting
obscured supernovae {SNe} in starburst galaxies. The inferred SN rate
is much higher than that obtained in previous optical campaigns, but
it is still significantly lower than expected by the high level star
formation of these systems. One possible explanation for the shortage
of SNe is that most of them occur in the nuclear region, where the
limited angular resolution of groundbased observations prevents their
detection. We propose NICMOS SNAP observations of a sample of
starburst galaxies already observed once by NICMOS, with the goal of
exploiting its sensitivity and angular resolution to detect nuclear
obscured SNe which might have been missed by groundbased surveys.
These observation will allow to assess the real SN rate in starbust
galaxies and deliver a sample of SN occurring in the extreme
environment of galactic nuclei. We expect to detect more than 55 SNe
{if the whole sample is observed}. If the number of SNe detected in
the program is much lower than expected it would prompt for a revision
of our understanding of the relation between the star formation rate
and the SN rate.

WFPC2 9725

The Long-term Observational Record of Uranus’ Atmosphere, its Rings,
and its Satellites: the WFPC2-ACS Link

Recording the seasonal change of Uranus is a key to understand
seasonal changes in atmospheres due to Uranus’ high obliquity. The
best record to date comes from WFPC2 imaging of Uranus since 1994. We
propose to image Uranus simultaneously with similar filters in WFPC2
and ACS so that this record can be extended with future ACS
observations. Without such an observation, the long-term record of
WFPC2 images cannot be linked with any future images because of
Uranus’ steep spectral features. Observations of the Uranian rings
over a wide range of sub-solar latitudes allow powerful constraints on
physical parameters, such as separation between ring particles. Our
proposed observations will provide the necessary link between previous
WFPC2 images and future ACS images near the ring-plane-crossing of
2007. The same reasoning applies to images of Uranian satellites,
where a consistent record over a wide range of sub-solar latitudes
yields information about satellite shape and albedo distribution.
Since Cycle 12 is the last Cycle of WFPC2, there will be no other
chance for the proposed observations. The investment of only two
orbits will significantly enhance the scientific value of the previous
45 WFPC2 orbits on Uranus. Only HST has the spatial resolution and
photometric stability for these studies.


Towards a global understanding of accretion physics – Clues from an UV
spectroscopic survey of cataclysmic variables

Accretion inflows and outflows are fundamental phenomena in a wide
variety of astrophysical environments, such as Young Stellar Objects,
galactic binaries, and AGN. Observationally, cataclysmic variables
{CVs} are particularly well suited for the study of accretion
processes. We are currently carrying out a Cycle 11 STIS UV
spectroscopic snapshot survey of CVs to fully exploit the diagnostic
potential of these objects for our understanding of accretion physics.
While the data obtained so far are of excellent quality, the number of
targets that will be observed in Cycle 11 is too small for a
statistically significant analysis {only 19 objects out of our 149
accepted Cycle 11 snapshot targets have been observed at the time of
writing}. We propose here to extend this survey into Cycle 12,
building a homogenous database of accretion disc and wind outflow
spectra covering a wide range of mass transfer rates and binary
inclinations. We will analyze these spectra with state-of-the-art
accretion disc model spectra {SYNDISK}, testing our current knowledge
of the accretion disc structure, and, thereby, providing new insight
into the so far not well understood process of viscous dissipation. We
will use our parameterised wind model PYTHON for the analysis of the
radiation driven accretion disc wind spectra, assessing the
fundamental question whether the mass loss rate correlates with the
disc luminosity. In addition, our survey data will identify a number
of systems in which the white dwarf significantly contributes to the
UV flux, permitting an analysis of the impact of mass accretion on the
evolution of these compact stars. This survey will triple the number
of currently available high-quality accretion disc / wind outflow /
accreting white dwarf spectra, and we waive our proprietary rights to
permit a timely use of this database.

WFPC2 9710

POMS Test Proposal: WFII backup parallel archive proposal

This is a POMS test proposal designed to simulate scientific plans.

WFPC2 9709

POMS Test Proposal: WFII parallel archive proposal

This is the generic target version of the WFPC2 Archival Pure Parallel
program. The program will be used to take parallel images of random
areas of the sky, following the recommendations of the 2002 Parallels
Working Group.

ACS 9675

CCD Daily Monitor

This program consists of basic tests to monitor, the read noise, the
development of hot pixels and test for any source of noise in ACS CCD
detectors. This programme will be executed once a day for the entire
lifetime of ACS.

ACS 9661

ACS Polarization Calibration

This proposal aims to calibrate the polarization modes most heavily
used in Cycle 11. We need L-flat observations, observations of a
polarized star and an unpolarized star, and an observation of an
extended polarized source.

ACS 9658

ACS Earth Flats

This program will obtain sequences of flat field images by observing
the bright Earth. Several UV filters from the interim calibration
program {9564} require additional exposures to obtain the required
illumination. A few UV filters from this program will be repeated to
monitor for changes in the flat fields and to verify the interim
results. Since no streaks are observed in the UV, the wavelength
coverage is extended to longer wavelengths in order to explore the
severity of streaks in the flats from clouds in the FOV. We have added
exposures for the HRC in the visible filters to verify the results
derived from the L-flat campaign and to explore the severity of
streaks. We have also added exposures on WFC using the minimum
exposure time and using filters which will not saturate the brightest
WFC pixel by more than 10 times the full well.

ACS 9657

ACS Internal Flat Field Stability

The flat field stability and characterization obtained during the
ground calibration and SMOV phases will be tested and verified through
a sub-sample of the filter set. Only internal exposures with the
calibration lamps will be required.

ACS/WFC 9648

External CTE Monitor

Monitor CTE changes during cycle 11. Determine CTE


Cycle 11 NICMOS dark current, shading profile, and read noise monitoring

The purpose of this proposal is to monitor the dark current, read
noise, and shading profile for all three NICMOS detectors throughout
the duration of Cycle 11. This proposal is a continuation of PID 9321
which covers the period between the end of SMOV3B and the onset of
Cycle 11.

WFPC2 9634

POMS Test Proposal: WFII targeted parallel archive proposal

The parallel opportunities available with WFPC2 in the neighborhood of
bright galaxies are treated in a slightly different way from the
normal pure parallels. Local Group galaxies offer the opportunity for
a closer look at young stellar populations. Narrow-band images in
F656N can be used both to identify young stars via their emission
lines, and to map the gas distribution in star-forming regions. Thus,
the filter F656N is added to the four standard filters. Near more
distant galaxies, up to about 10 Mpc, we can map the population of
globular clusters; for this purpose, F300W is less useful, and only
F450W, F606W, and F814W will be used.

STIS 9633

STIS parallel archive proposal – Nearby Galaxies – Imaging and

Using parallel opportunities with STIS which were not allocated by the
TAC, we propose to obtain deep STIS imagery with both the Clear
{50CCD} and Long-Pass {F28X50LP} filters in order to make
color-magnitude diagrams and luminosity functions for nearby galaxies.
For local group galaxies, we also include G750L slitless spectroscopy
to search for e.g., Carbon stars, late M giants and S-type stars. This
survey will be useful to study the star formation histories, chemical
evolution, and distances to these galaxies. These data will be placed
immediately into the Hubble Data Archive.

STIS 9615

Cycle 11 MAMA Dark Monitor

This test performs the routine monitoring of the MAMA detector dark
noise. This proposal will provide the primary means of checking on
health of the MAMA detectors systems through frequent monitoring of
the background count rate. The purpose is to look for evidence of
change in dark indicative of detector problem developing.

STIS 9614

STIS CCD Imaging Flats C11

Investigate flat-field stability over a monthly period.

STIS 9613

STIS CCD Spectroscopic Flats C11

Obtain CCD flats on the STIS CCD in spectroscopic mode.


CCD Read Noise Monitor

This proposal measures the read noise of all the amplifiers {A, B, C,
D} on the STIS CCD using pairs of bias frames. Full frame and binned
observations are made in both Gain 1 and Gain 4, with binning factors
of 1×1, 1×2, 2×1 and 2×2. All exposures are internals. Pairs of visits
are scheduled for monthly execution.

STIS 9608

CCD Bias Monitor – Part 2

Monitor the bias in the 1×1, 1×2, 2×1, and 2×2 bin settings at gain=1,
and 1×1 at gain = 4, to build up high-S/N superbiases and track the
evolution of hot columns.

STIS 9606

CCD Dark Monitor-Part 2

Monitor the darks for the STIS CCD.

FGS/CAL 9602

Long Term Monitoring of FGS1r in Position Mode

It is known from our experience with FGS3, and later with FGS1r, that
an FGS on orbit experiences long term evolution, presumably due to
disorption of water from the instrument’s graphite epoxy composites.
This manifests principally as a change in the plate scale and
secondarily as a change in the geometric distortions. These effects
are well modeled by adjustments to the rhoA and kA parameters which
are used to transform the star selector servo angles into FGS {x, y}
detector space coordinates. By observing the relative positions of
selected stars in a standard cluster at a fixed telescope pointing and
orientation, the evolution of rhoA and kA can be monitored and
calibrated to preserve the astrometric performance of FGS1r.

WFPC2 9596


This calibration proposal is the Cycle 11 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
{gain 7 and gain 15}, a test for quantum efficiency in the CCDs, and a
monitor for possible buildup of contaminants on the CCD windows.

WFPC2 9595


This dark calibration program obtains 3 dark frames every day to
provide data for monitoring and characterizing the evolution of hot

WFPC2 9592

WFPC2 CYCLE 11 Standard Darks

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.

ACS/WFPC2 9481

Pure Parallel Near-UV Observations with WFPC2 within High-Latitude ACS
Survey Fields

In anticipation of the allocation of ACS high-latitude imaging
survey{s}, we request a modification of the default pure parallel
program for those WFPC2 parallels that fall within the ACS survey
field. Rather than duplicate the red bands which will be done much
better with ACS, we propose to observe in the near-ultraviolet F300W
filter. These data will enable study of the rest-frame ultraviolet
morphology of galaxies at 0<z<1. We will determine the morphological
k-correction, and the location of star formation within galaxies,
using a sample that is likely to be nearly complete with
multi-wavelength photometry and spectroscopic redshifts. The results
can be used to interpret observations of higher redshift galaxies by


NICMOS Post-SAA calibration – CR Persistence Part 2

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 USEAFTER
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 DARKSs. 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 10040

Test of new STIS pseudo-aperture positions

This proposal will check positions and throughputs for E1, E2, D1, and
WEDGEA0.6 pseudoaperture positions. The E1 aperture positions have
been slightly revised to better reflect on-orbit measurements, and the
other new pseudoaperture positions have been recently defined. The new
aperture positions divide into three groups: {1} E2 apertures for
better row 900 fringe flats: 52X2E2 52X0.5E2 52X0.2E2 {2} D1 apertures
for low noise FUV MAMA 1st order spectra: 52X2D1 52X0.5D1 52X0.2D1
52X0.1D1 52X0.05D1 F25SRF2D1 F25QTZD1 25MAMAD1 {3} a new coronagraphic
wedge position located at a narrower part of the coronagraphic wedge:

STIS/CCD 10000

STIS Pure Parallel Imaging Program: Cycle 12

This is the default archival pure parallel program for STIS during cycle


Significant Spacecraft Anomalies: (The following are preliminary
reports of potential non-nominal performance that will be

                        SCHEDULED     SUCCESSFUL    FAILURE TIMES
FGS GSacq            33                        33
FGS REacq            30                         30
FHST Update          69                         69



1147-0 – Adjust Recharge Ratio Limits for High Sun DOY 2003/235-241.
(expired, original limits restored) @ 241/1200z

1142-1 – Bay 5 Temperature Change (expired, limits restored to PDB
values) @ 241/2030z

1151-0 – Change Limit for OM2RDETQ for additional MCE 2 reset @ 242/1124z

1148-1 – Adjust ACS Error Count Limit @ 244/0159z


Completed Command Timing Comparison (SUN/SGI) testing 24011:00Z –
18:43Z using CCS "D" and "B" Strings. All test objectives were
completed. Results, once again, indicate the SUN "D" String
performance is significantly faster. While commanding FIVEBLCKs in a
"NoVerify" mode, a 15% – 30% increase was seen and in "Countcheck"
mode, a 10% – 20% increase was seen. The SGI "B" String remains
nominal. With this testing, Sys Admin monitored the test and provided
data capture. This data will be reviewed and a follow-up report will
be provided.

SpaceRef staff editor.