Status Report

NASA Hubble Space Telescope Daily Status Report # 3564

By SpaceRef Editor
March 5, 2004
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HUBBLE SPACE TELESCOPE – Continuing to collect World Class Science




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.


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.


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.

ACS/WFC 10046

CCD Hot Pixel Annealing

Hot pixel annealing will be performed once every 4 weeks. The CCD TECs
will be turned off and heaters will be activated to bring the detector
temperatures to about +20C. This state will be held for approximately
12 hours, after which the heaters are turned off, the TECs turned on,
and the CCDs returned to normal operating condition. To assess the
effectiveness of this procedure, a bias and two dark images will be
taken after the annealing procedure for both WFC and HRC. The HRC
darks are taken in parallel with the WFC darks.


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

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.


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 10017

CCD Dark Monitor-Part 1

Monitor the darks for the STIS CCD.

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 10085

STIS Pure Parallel Imaging Program: Cycle 12

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

STIS/MA1/MA2 10032

MAMA Full Field Sensitivity Monitor & PSF Check

The purpose of this program is to monitor the sensitivity of the MAMA
detectors over the full field. This is achieved by observing globular
cluster NGC6681 once during Cycle 12. The data can be directly
compared with similar data obtained in Cycles 7, 8, 9, 10 and 11.

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 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 10090

WFII backup parallel archive proposal

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


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

                            SCHEDULED     SUCCESSFUL    FAILURE TIMES
FGS GSacq                10                       10
FGS REacq                03                        03
FHST Update              12                        12


CCS Release – PACOR A PSS PF-13 Interface Test scheduled
065/12:00Z – 20:00Z with GDOC, HITT, PACOR A, OPUS, and SOC using CCS
"C" with CCS Release and "D" Strings with CCS Release
and PRD O06300ST. The purpose of this testing is to verify PACOR A
can ingest various science data products from PF-13 and the PSS.

SpaceRef staff editor.