Status Report

NASA Hubble Space Telescope Daily Report # 3565

By SpaceRef Editor
March 10, 2004
Filed under , ,

HUBBLE SPACE TELESCOPE – Continuing to collect World Class Science




NIC3 9999

The COSMOS 2-Degree ACS Survey NICMOS Parallels

The COSMOS 2-Degree ACS Survey NICMOS Parallels. This program is a
companion to program 9822.

S/C/NIC1/NIC3 9994

NICMOS Focus Stability

The purpose of this activity is to determine if the best focus
determined in SMOV is stable. This program will execute in
approximately one month intervals starting about 1 month after the
last execution of proposal 8980.

ACS 9984

Cosmic Shear With ACS Pure Parallels

Small distortions in the shapes of background galaxies by foreground
mass provide a powerful method of directly measuring the amount and
distribution of dark matter. Several groups have recently detected
this weak lensing by large-scale structure, also called cosmic shear.
The high resolution and sensitivity of HST/ACS provide a unique
opportunity to measure cosmic shear accurately on small scales. Using
260 parallel orbits in Sloan textiti {F775W} we will measure for the
first time: beginlistosetlength sep0cm setlengthemsep0cm setlength
opsep0cm em the cosmic shear variance on scales <0.7 arcmin, em the
skewness of the shear distribution, and em the magnification effect.
endlist Our measurements will determine the amplitude of the mass
power spectrum sigma_8Omega_m^0.5, with signal-to-noise {s/n} ~ 20,
and the mass density Omega_m with s/n=4. They will be done at small
angular scales where non-linear effects dominate the power spectrum,
providing a test of the gravitational instability paradigm for
structure formation. Measurements on these scales are not possible
from the ground, because of the systematic effects induced by PSF
smearing from seeing. Having many independent lines of sight reduces
the uncertainty due to cosmic variance, making parallel observations

STIS 9973

Intensive Coverage of the Eta Carinae Event in 2003

For a variety of reasons, HST can provide a very special and unique
data set when Eta Car experiences its next spectroscopic event in
mid-2003. Explaining the phenomenon is only part of the motivation.
This star and its ejecta have unique characteristics that make them
important for several branches of astrophysics; and when a
spectroscopic event occurs, it’s like varying the parameters in an
experiment {or rather, set of experiments}. The 2003 event may be the
only chance in the forseeable future to obtain such a data set,
especially with HST. Eta Carinae has extreme parameters; it is
mysterious in surprisingly basic ways; and HST/STIS can gather useful
data on it at a terrific rate. As we explain below, the proposed data
set will be valuable in several independent ways: It will help solve a
specific set of current problems, it will constitute a large and
unique archival data base for both stellar and nebular astrophysics,
and it will be well-suited for educational uses.


Probing the Dynamics and Shock Physics of the Cas A Supernova Remnant

Cassiopeia A {Cas A; SN 1680} is the youngest known and closest
example of an oxygen-rich, core-collapse supernova remnant. A two-year
WFPC2 survey of part of the remnant yielded many new insights
including realization of the stunning amount of fine-scale detail
present in the ejecta, and the first precise location of the reverse
shock front in the main shell via rapid emission and structural
changes visible over 2 yrs. In addition, these data revealed over 100
new ejecta knots located out ahead of the forward blast wave in a
small region where only a handful were known from ground-based images.
We propose a follow-up survey program aimed at obtaining hi-res images
of the entire remnant in the ejecta’s four major emission lines. A
separate set of ACS and NIC3 [Si VI] images of the NW reverse shock
filaments will be taken 3-4 months following the main Cycle 12 survey
images. These will allow us to the trace individual ejecta knot
deceleration dynamics, excitation, and evolution during reverse shock
passage. Analysis of the emission line fluxes will make use of custom
shock models generated by us for Cas A. These data will also provide
data on outer knot chemistry and expansion asymmetries particularly in
regard to the collimation of the NE and SW jets of O, Si, Ca-rich
ejecta. A major aim of this program is to acquire a superb two-year
image database covering the entire remnant to allow a detailed shock
physics and dynamics study.

NIC2 9834

Finding Planets in the Stellar Graveyard: A Faint Companion Search of
White Dwarfs with NICMOS

We propose to do a deep search for substellar objects in orbit around
white dwarfs with the newly refurbished NICMOS camera as part of the
PI’s doctoral thesis work. Direct imaging of planets around main
sequence stars is difficult due to the large contrast ratio, a problem
which is much less severe for companions to white dwarfs. White dwarfs
are not usually considered in planet searches but recent theoretical
work and observations are motivating new searches for planetary
systems and dust disks around DAZ white dwarfs. We propose to conduct
the search with the NIC2 coronagraph to find resolved companions and
do photometry to search for unresolved companions through Near-IR
excesses. We estimate that the survey will be sensitive to brown
dwarfs, high mass jovian planets, and dust disks. By probing a wide
range of orbital separations and companion masses, this survey will
help to answer questions about the brown dwarf desert, common envelope
evolution, and planet formation. HST and NICMOS provide a unique
capability to do this search, as no ground based observatory with AO
can adequately search for faint companions as close and with such high


The COSMOS 2-Degree ACS Survey

We will undertake a 2 square degree imaging survey {Cosmic Evolution
Survey — COSMOS} with ACS in the I {F814W} band of the VIMOS
equatorial field. This wide field survey is essential to understand
the interplay between Large Scale Structure {LSS} evolution and the
formation of galaxies, dark matter and AGNs and is the one region of
parameter space completely unexplored at present by HST. The
equatorial field was selected for its accessibility to all
ground-based telescopes and low IR background and because it will
eventually contain ~100, 000 galaxy spectra from the VLT-VIMOS
instrument. The imaging will detect over 2 million objects with I> 27
mag {AB, 10 sigma}, over 35, 000 Lyman Break Galaxies {LBGs} and
extremely red galaxies out to z ~ 5. COSMOS is the only HST project
specifically designed to probe the formation and evolution of
structures ranging from galaxies up to Coma-size clusters in the epoch
of peak galaxy, AGN, star and cluster formation {z ~0.5 to 3}. The
size of the largest structures necessitate the 2 degree field. Our
team is committed to the assembly of several public ancillary datasets
including the optical spectra, deep XMM and VLA imaging, ground-based
optical/IR imaging, UV imaging from GALEX and IR data from SIRTF.
Combining the full-spectrum multiwavelength imaging and spectroscopic
coverage with ACS sub-kpc resolution, COSMOS will be Hubble’s ultimate
legacy for understanding the evolution of both the visible and dark

NIC2 9798

What’s The Point? Deep NICMOS Imaging of the Central X-ray Point
Source in Cas A

First-light Chandra X-ray Observatory images revealed an enigmatic
central point source in Cas A, the Galaxy’s youngest known supernova
remnant {SN 1680}. The object lies within 7 arcsec of the remnant’s
expansion center and is presumably the remnant’s neutron star with
unusual properties. Deep Cycle 9 STIS observations and Keck’s near-IR
imaging detected only one object within the Chandra positional error
circle, and this appears to be a foreground star. These optical and
NIR upper limits already prove that the X-ray source cannot be a field
star, an AGN, an ordinary pulsar, or an X-ray binary with any known
type of optical companion. A likely possibility is that it is a very
young magnetar that will evolve into an Anomalous X-ray Pulsar or a
Soft Gamma-ray Repeater. Due to the high extinction to Cas A, deep
NICMOS imaging offers the best way to search for a counterpart. Here
we propose obtaining NIC2 H band images which will go to H=25.7 —
almost 6 mags deeper than the previous searches and about 2 mags
deeper than is realistically possible with Keck or Subaru. The
high-resolution capability of NIC2 will also limit potential source
confusion in this galactic plane region. We will obtain matching J
images {to 27.2 mag} to provide color information on the candidate
objects. These ultra-deep NICMOS images will either detect the
counterpart and hence determine its nature, or place severe
constraints on the properties of the point source.

STIS 9786

The Next Generation Spectral Library

We propose to continue the Cycle 10 snapshot program to produce a Next
Generation Spectral Library of 600 stars for use in modeling the
integrated light of galaxies and clusters. This program is using the
low dispersion UV and optical gratings of STIS. The library will be
roughly equally divided among four metallicities, very low {[Fe/H] lt
-1.5}, low {[Fe/H] -1.5 to -0.5}, near-solar {[Fe/H] -0.3 to 0.1}, and
super-solar {[Fe/H] gt 0.2}, well-sampling the entire HR-diagram in
each bin. Such a library will surpass all extant compilations and have
lasting archival value, well into the Next Generation Space Telescope
era. Because of the universal utility and community-broad nature of
this venture, we waive the entire proprietary period.


The local Hubble flow and the density field within 6 Mpc

Great progress has been made recently in accurate distance
measurements of nearby galaxies beyond the Local Group based on the
luminosity of the tip of the red giant branch {TRGB}. Over the last
three years, snapshot surveys with HST have provided us with the TRGB
distances for more than a hundred nearby galaxies obtained with an
accuracy of about 10%. The local velocity field within 5 Mpc exhibits
a significant anisotropy which disagrees with a spherical
Virgo-centric flow. The local Hubble flow is very cold, with 1-D rms
deviations of ~30 km/s. Cosmological simulations with Cold Dark Matter
can only realize such low dispersions with a combination of a low mean
density of matter and a substantial component with negative pressure.
There may be a constraint on the equation of state w=-p/rho. Our
observations will concentrate on 116 galaxies whose expected distances
lie within 4 – 6 Mpc, allowing us to trace a Dark Matter distribution
in the Local Volume with twice the information currently available.
The program is a good one for SNAP mode because the order and rate
that the observations are made are not very important, as long as
there is good completion over several years.

NIC2 9768

Enabling Coronagraphic Polarimetry with NICMOS

We propose to enable a new mode on NICMOS that combines the powerful
diffracted light rejection of the coronagraph with the diagnostic
power of polarimetry. This new capability will open a new regime in
high contrast imaging that has not been possible before. We will
enable this capability by observing calibration targets with the
coronagraph and the NIC2 polarizers in place. The enabled science
includes, but is not limited to, detection and imaging of
circumstellar debris in polarized light, the polarized emission
surrounding bright planetary nebulae, and the extended structure
around bright active galaxies. A similar capability is possible with
the ACS, and therefore HST would provide the only platform for this
extremely high contrast imaging covering the entire near-UV, optical
and near-infrared wavelength regime. Only the combined HST NICMOS
system has the combined resolution and stability {especially with the
NCS} to provide high spatial resolution, coronagraphic, near-infrared
polarimetry in the foreseeable future. The technique is absolutely
unique to HST and will enable a new regime in high contrast imaging.

ACS/WFC 9766

The Globular Cluster Systems of Spiral Galaxies along the Hubble

While the globular cluster {GC} systems of ellipticals and ongoing
mergers have been relatively well-studied with HST, very little is
known about the GC systems of spirals besides the Milky Way and M31.
To constrain GC/galaxy formation models, especially where spirals are
the merger progenitors of ellipticals, it is crucial to understand
their GC properties. We propose to obtain ACS images of three edge-on
spirals, spanning the Hubble sequence, with Keck spectroscopic
follow-up. This will effectively double the number of well-studied
spiral systems. We will detect 100-200 GCs per galaxy, sufficient to
reveal GC subpopulations, their relative numbers, radial trends, and
dependences on Hubble type {e.g., a bulge vs. disk origin for red
GCs}. For half of our GCs we will be able to measure individual sizes.
By providing a much-needed comparative benchmark, these data will
allow researchers to better exploit the large existing HST database of
GCs in E/S0 galaxies.

ACS/HRC 9747

An Imaging Survey of the Statistical Frequency of Binaries Among
Exceptionally-Young Dynamical Families in the Main Asteroid Belt

We propose an ambitious SNAPSHOT program to determine the frequency of
binaries among two very young asteroid families in the Main Belt, with
potentially profound implications. These families {of C- and S-type}
have recently been discovered {Nesvorny et al. 2002, Nature 417, 720},
through dynamical modeling, to have been formed at 5.8 MY and 8.3 MY
ago in catastrophic impact events. This is the first time such
precise and young ages have been assigned to a family. Main-belt
binaries are almost certainly produced by collisions, and we would
expect a young family to have a significantly higher frequency of
binaries than the background, because they may not yet have been
destroyed by impact or longer-term gravitational instabilities. In
fact, one of the prime observables from such an event should be the
propensity for satellites. This is the best way that new numerical
models for binary production by collisions {motivated largely by our
ground-based discoveries of satellites among larger asteroids}, can be
validated and calibrated. HST is the only facility that can be used to
search for binaries among such faint objects {V>17.5}. We will also
measure two control clusters, one being an "old" family, and the other
a collection of background asteroids that do not have a family
association, and further compare with our determined value for the
frequency of large main-belt binaries {2%}. We request visits to 180
targets, using ACS/HRC.

STIS/MA1/MA2 9739

Are We Missing the Dominant Sites of Star Formation in Local UV-Bright

We propose to explore the ages, extinctions, and masses of young
stellar clusters in four nearby dwarf starburst galaxies {He 2-10, NGC
5253, NGC 4214, and IIZw40}. We will combine available archival data
with new, high resolution HST observations from the ultraviolet to the
infrared. All four galaxies are known from ground based radio/infrared
observations to contain highly obscured, massive stellar clusters,
which dominate the far infrared flux. Despite the fact that almost all
of the infrared flux comes from regions which are obscured at UV and
optical wavelengths, these galaxies are consistent with the well known
correlation between the UV slope {beta} and the ratio of far infrared
flux to ultraviolet flux at 1600 Angstroms. Because the UV and IR
fluxes are decoupled, this observation implies that a simple
foreground screen model, where UV photons from hot stars are
reprocessed into the infrared by local dust, is not the proper
interpretation for why these galaxies follow the beta relation. We
propose to investigate the underlying mechanisms responsible for this
observed correlation in these UV bright galaxies, and explore the
implication for high redshift starbursts.

ACS/WFC 9701

ACS Default {Archival} Pure Parallel Program II

The proposal is designed to test ACS pure parallels in POMS.

ACS/WFC 9575

Default {Archival} Pure Parallel Program.

The Advanced Camera for Surveys (WFC) was used to test ACS pure
parallels in POMS.


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.

WFPC2 10090

WFII backup parallel archive proposal

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

STIS/CCD 10085

STIS Pure Parallel Imaging Program: Cycle 12

This is the default archival pure parallel program for STIS during
cycle 12.

WFPC2 10084

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.

WFPC2 10073

Earth Flats

This proposal monitors flatfield stability. This proposal obtains
sequences of Earth streak flats to construct high quality flat fields
for the WFPC2 filter set. These flat fields will allow mapping of the
OTA illumination pattern and will be used in conjuction with previous
internal and external flats to generate new pipeline superflats. These
Earth flats will complement the Earth flat data obtained during cycles

WFPC2 10072


This calibration proposal is the Cycle 12 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 10070

WFPC2 CYCLE 12 Supplemental Darks Part 2/3

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

WFPC2 10068

WFPC2 CYCLE 12 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.


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 internal CTE monitor

The charge transfer efficiency {CTE} of the ACS CCD detectors will
decline as damage due to on-orbit radiation exposure accumulates. This
degradation will be closely monitored at regular intervals, because it
is likely to determine the useful lifetime of the CCDs. All the data
for this program is acquired using internal targets {lamps} only, so
all of the exposures should be taken during Earth occultation time
{but not during SAA passages}. This program emulates the ACS
pre-flight ground calibration and post-launch SMOV testing {program
8948}, so that results from each epoch can be directly compared.
Extended Pixel Edge Response {EPER} and First Pixel Response {FPR}
data will be obtained over a range of signal levels for both the Wide
Field Channel {WFC}, and the High Resolution Channel {HRC}.

STIS/MA1 10034

Cycle 12 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/CCD 10022

STIS CCD Hot Pixel Annealing Cycle 12

The effectiveness of the CCD hot pixel annealing process is assessed
by measuring the dark current behavior before and after annealing and
by searching for any window contamination effects. In addition CTE
performance is examined by looking for traps in a low signal level
flat. Follows on from proposal 9612.

STIS/CCD 10019

CCD Bias Monitor – Part 1

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/CCD 10017

CCD Dark Monitor-Part 1

Monitor the darks for the STIS CCD.


Focus Monitor

The focus of HST is measured from WFPC2/PC and ACS/HRC images of
stars. Multiple exposures are taken in parallel over an orbit to
determine the influence of breathing on the derived mean focus.
Observations are taken of clusters with suitable orientations to
ensure stars appear in all fields.


Significant Spacecraft Anomalies: (The following are preliminary
reports of potential non-nominal performance that will be
investigated.) None



  • 1115-0 CCC IPCONFIG Connections @ 064/17:31z
  • 1205-0 Return Thermal Limits to Database Values @ 065/16:50z
  • 1206-0 Change Limits MAMA1 Threshold Voltage @ 067/01:15z

                            SCHEDULED     SUCCESSFUL    FAILURE TIMES
FGS GSacq                43                       43
FGS REacq                11                       11
FHST Update              69                       69


SMS SA068O01 products are the first use of a new Basefile,
ms_04068.bas, which reduces the number of cycles on the FHST shutters.
This change will executed FHST AutoMaps only after a GS Acquisition,
rather than after the GS Acquisition and the first commanding.

SpaceRef staff editor.