HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science

DAILY REPORT # 4159

PERIOD COVERED: UT July 19, 2006 (DOY 200)

OBSERVATIONS SCHEDULED

ACS/HRC 10512

Search for Binaries Among Faint Jupiter Trojan Asteroids

We propose an ambitious SNAPSHOT program to survey faint Jupiter Trojan
asteroids for binary companions. We target 150 objects, with the
expectation of acquiring data on about 50%. These objects span Vmag =
17.5-19.5, a range inaccessible with ground-based adaptive optics. We
now have a significant sample from our survey of brighter Trojans to
suggest that the binary fraction is similar to that which we find among
brighter main-belt asteroids, roughly 2%. However, our observations
suggest a higher binary fraction for smaller main-belt asteroids,
probably the result of a different formation mechanism {evident also
from the physical characteristics of the binaries}. Because the
collision environment among the Trojans is similar to that of the Main
Belt, while the composition is likely to be very different, sampling the
binary fraction among the fainter Trojans should help us understand the
collisional and binary formation mechanisms at work in various
populations, including the Kuiper Belt, and help us evaluate theories
for the origin of the Trojans. Calibration of and constraints on models
of binary production and collisional evolution can only be done using
these large-scale, real-life physical systems that we are beginning now
to find and utilize.

ACS/HRC 10598

ACS Imaging of Fomalhaut: A Rosetta Stone for Debris Disks Sculpted by
Planets

The Sun and roughly 15% of stars are surrounded by dust disks
collisionally replenished by asteroids and comets. Disk structure can be
directly tied to the dynamical influence of more massive bodies such as
planets. For example, planetary perturbations offset the center of our
zodiacal dust disk ~0.01 AU away from the Sun and also maintain a ~40 AU
radius inner edge to our Kuiper Belt. Here we propose follow-up
observation to the first optical detection of reflected light from dust
grains surrounding the nearby star Fomalhaut using HST/ACS. We find a
belt of material between 133 and 158 AU radius that has a center
position offset ~15 AU from the stellar position, and with a sharp inner
edge. A tenuous dust component interior to the belt is also detected in
the southeast. Given Fomalhaut's proximity to the Sun {7.7 pc}, these
images represent the closest and highest angular resolution view of an
extrasolar analog to our Kuiper Belt. The center of symmetry offset and
the sharp inner edge of Fomalhaut's belt are evidence for planet-mass
objects orbiting the star as predicted by dynamical theory and
simulations. We propose comprehensive follow-up ACS imaging to fully
exploit this discovery and map the disk around its entire circumference
with higher signal-to-noise and at multiple wavelengths. HST/ACS is
certainly the only facility capable of performing this relatively wide
field optical study at high contrast ratios and diffraction-limited
resolution. The Cycle 14 data will provide key measurements of belt
width as a function of azimuth, the scattered light color of the belt
versus the inner dust component, and the azimuthal structure of the
belt. These data will be used to constrain dynamical models of
resonances and shepherding that ultimately elucidate the dynamical
properties of planet-mass objects in the system.

ACS/HRC 10627

A Snapshot Survey of Post-AGB Objects and Proto-Planetary Nebulae

We propose an ACS/HRC snapshot survey of 50 post-AGB sources, objects
which have evolved from the AGB but may or may not become planetary
nebulae {PNe}. This survey will complement existing HST images of
proto-planetary nebulae {PPNe} and PNe in addressing circumstellar
envelope morphology as a function of: 1} the progenitor star mass; 2}
the chemical composition; and 3} evolutionary stage. We will connect the
observed diversity of nebualar shapes with the main physical and
chemical conditions characterizing post-AGB objects, to identify the
mechanism that breaks the symmetry of AGB mass loss. To our knowledge,
no previous HST projects have been specifically designed to address this
issue. From our database of 360 post-AGB candidates, we have selected
approximately 50 targets, none of which have been or are being observed
with HST, to sample different central star masses, chemical
compositions, and evolutionary stages, uniformly across the sky. These
new data will also provide important constraints to a quantitative
analysis of Spitzer Space Telescope {SST} observations planned for a
similar sample of objects. We will model the HST images and SST spectra
using our axisymmetric dust code 2-Dust, to derive dust density
distributions, pole to equator density ratios, dust shell masses,
inclination angles as well as dust composition.

ACS/HRC/WFC 10758

ACS CCDs daily monitor

This program consists of a set of basic tests to monitor, the read
noise, the development of hot pixels and test for any source of noise in
ACS CCD detectors. The files, biases and dark will be used to create
reference files for science calibration. This programme will be for the
entire lifetime of ACS. Changes from cycle 13:- The default gain for WFC
is 2 e- /DN. As before bias frames will be collected for both gain 1 and
gain 2. Dark frames are acquired using the default gain {2}. This
program cover the period May, 31 2006- Oct, 1- 2006. The first half of
the program has a different proposal number: 10729.

ACS/WFC 10626

A Snapshot Survey of Brightest Cluster Galaxies and Strong Lensing to z
= 0.9

We propose an ACS/WFC snapshot survey of the cores of 150 rich galaxy
clusters at 0.3 < z < 0.9 from the Red Sequence Cluster Survey {RCS}. An
examination of the galaxian light in the brightest cluster galaxies,
coupled with a statistical analysis of the strong- lensing properties of
the sample, will allow us to contrain the evolution of both the baryonic
and dark mass in cluster cores, over an unprecedented redshift range and
sample size. In detail, we will use the high-resolution ACS images to
measure the metric {10 kpc/h} luminosity and morphological disturbances
around the brightest clusters galaxies, in order to calibrate their
accretion history in comparison to recent detailed simulations of
structure formation in cluster cores. These images will also yield a
well-defined sample of arcs formed by strong lensing by these clusters;
the frequency and detailed distribution {size, multiplicity, redshifts}
of these strong lens systems sets strong constraints on the total mass
content {and its structure} in the centers of the clusters. These data
will also be invaluable in the study of the morphological evolution and
properties of cluster galaxies over a significant redshift range. These
analyses will be supported by extensive ongoing optical and
near-infrared imaging, and optical spectroscopy at Magellan, VLT and
Gemini telescopes, as well as host of smaller facilities.

CAL/ACS 10735

SBC MAMA Recovery

This proposal is designed for the initial turn-on of the ACS MAMA
detector and to permit recovery after an anomalous shutdown. Anomalous
shutdowns can occur as a result of bright object violations which
trigger the Bright Scene Detection or Software Global Monitors.
Anomalous shutdowns can also occur as a result of MAMA hardware
problems. The Initial MAMA turn-on/recovery from anomalous shutdown
consists of three tests: a signal processing electronics check, high
voltage ramp-up to an intermediate voltage, and high voltage ramp-up to
the full operating voltage. During each of the two high voltage
ramp-ups, diagnostics are performed during a dark ACCUM. The turn-on is
followed by a MAMA Fold Analysis .

NIC1/NIC2/NIC3 8794

NICMOS Post-SAA calibration - CR Persistence Part 5

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.

NIC2 10906

The Fundamental Plane of Massive Gas-Rich Mergers: II. The QUEST QSOs

We propose deep NICMOS H-band imaging of a carefully selected sample of
23 local QSOs. This program is the last critical element of a
comprehensive investigation of the most luminous mergers in the nearby
universe, the ultraluminous infrared galaxies {ULIRGs} and the quasars.
This effort is called QUEST: Quasar / ULIRG Evolutionary STudy. The
high-resolution HST images of the QUEST QSOs will complement an
identical set of images on the ULIRG sample obtained during Cycle 12, an
extensive set of ground-based data that include long-slit NIR spectra
from a Large VLT Program, and a large set of mid-infrared spectra from a
Cycle 1 medium-size program with Spitzer. This unique dataset will allow
us to derive with unprecedented precision structual, kinematic, and
activity parameters for a large unbiased sample of objects spanning the
entire ULIRG/QSO luminosity function. These data will refine the
fundamental plane of massive gas-rich mergers and enable us to answer
the following quesitons: {1} Do ultraluminous mergers form elliptical
galaxies, and in particular, giant ellipticals? {2} Do ULIRGs evolve
into optical bright QSOs? The results from this detailed study of
massive mergers in the local universe will be relevant to understanding
the basic physical processes involved in creating massive early-type
host on the one hand, and growing/feeding embedded massive black holes
on the other, in major galaxy mergers. This is an important question
since 50% of cosmic star formation at high-z and most of the big BHs
appear to be formed in this process.


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:
#17859-0 GenSlew for Proposal 10487 slot#3 @200/18:51z
#17860-0 GenSlew for Proposal 10487 slot#4 @200/18:53z

COMPLETED OPS NOTES: (None)

                       SCHEDULED          SUCCESSFUL
FGS GSacq                  13                13                                  
FGS REacq                  00                00                
OBAD with Maneuver     26                26   

SIGNIFICANT EVENTS:  (None)

-Lynn

Lynn F. Bassford
CHAMP HST Missions Operations Manager
Lockheed Martin Technical Operations
GSFC PH#: 301-286-2876

"The Hubble Space Telescope is the Babe Ruth of astronomical observatories, the Muhammad Ali of cosmic photography "            - Robert Roy Britt, space.com 7-14-4
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