HUBBLE SPACE TELESCOPE - Continuing to collect World Class
Science
DAILY REPORT #4731
PERIOD COVERED: 5am November 4 - 5am November 5, 2008 (DOY
309/1000z-310/1000z)
OBSERVATIONS SCHEDULED
FGS 11212/11901
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.
S/C 4974
TRTTEST
The Transient Response Test is for the periodic
performance monitoring
of the FGS 2R servo A mechanism.
WFPC2 11103
A Snapshot Survey of The Most Massive Clusters of Galaxies
We propose the continuation of our highly successful
SNAPshot survey of
a sample of 125 very X-ray luminous clusters in the
redshift range
0.3-0.7. As demonstrated by the 25 snapshots obtained so
far in Cycle14
and Cycle15 these systems frequently exhibit strong
gravitational
lensing as well as spectacular examples of violent galaxy
interactions.
The proposed observations will provide important
constraints on the
cluster mass distributions, the physical nature of
galaxy-galaxy and
galaxy-gas interactions in cluster cores, and a set of
optically bright,
lensed galaxies for further 8-10m spectroscopy. All of our
primary
science goals require only the detection and
characterization of
high-surface-brightness features and are thus achievable
even at the
reduced sensitivity of WFPC2. Because of their high
redshift and thus
compact angular scale our target clusters are less
adversely affected by
the smaller field of view of WFPC2 than more nearby
systems.
Acknowledging the broad community interest in this sample
we waive our
data rights for these observations. Due to a clerical
error at STScI our
approved Cycle15 SNAP program was barred from execution
for 3 months and
only 6 observations have been performed to date -
reinstating this SNAP
at Cycle16 priority is of paramount importance to reach
meaningful
statistics.
WFPC2 11289
SL2S: The Strong Lensing Legacy Survey
Recent systematic surveys of strong galaxy-galaxy lenses
{CLASS, SLACS,
GOODS, etc.} are producing spectacular results for galaxy
masses roughly
below a transition mass M~10^13 Mo. The observed lens
properties and
their evolution up to z~0.2, consistent with numerical
simulations, can
be described by isothermal elliptical potentials. In
contrast, modeling
of giant arcs in X-ray luminous clusters {halo masses M
>~10^13 Mo}
favors NFW mass profiles, suggesting that dark matter
halos are not
significantly affected by baryon cooling. Until recently,
lensing
surveys were neither deep nor extended enough to probe the
intermediate
mass density regime, which is fundamental for
understanding the assembly
of structures. The CFHT Legacy Survey now covers 125
square degrees, and
thus offers a large reservoir of strong lenses probing a
large range of
mass densities up to z~1. We have extracted a list of 150
strong lenses
using the most recent CFHTLS data release via automated
procedures.
Following our first SNAPSHOT proposal in cycle 15, we
propose to
continue the Hubble follow-up targeting a larger list of
130 lensing
candidates. These are intermediate mass range candidates
{between
galaxies and clusters} that are selected in the redshift
range of 0.2-1
with no a priori X-ray selection. The HST resolution is
necessary for
confirming the lensing candidates, accurate modeling of
the lenses, and
probing the total mass concentration in galaxy groups up
to z~1 with the
largest unbiased sample available to date.
WFPC2 11795
WFPC2 Cycle 16 UV Earth Flats
Monitor flat field stability. This proposal obtains
sequences of earth
streak flats to improve the quality of pipeline flat
fields for the
WFPC2 UV filter set. These Earth flats will complement the
UV earth flat
data obtained during cycles 8-15.
FLIGHT OPERATIONS SUMMARY:
Significant Spacecraft Anomalies: (The following are
preliminary reports
of potential non-nominal performance that will be
investigated.)
HSTARS:
11566 - GSACQ (2,0,2) failed
GSACQ(2,0,2) at 309/19:20:20 failed to RGA control with Search Radius
Limit exceeded on FGS 2 at 19:24:59.
Observations affected: Astrometry only, proposal 1121
COMPLETED OPS REQUEST:
18349-0 - FGS-2R TRTT #20 @ 309/1527z
COMPLETED OPS NOTES: (None)
SCHEDULED
SUCCESSFUL
FGS GSacq
11
10
FGS REacq
01
01
OBAD with Maneuver
28
28
SIGNIFICANT EVENTS:
The transient response trending test (TRTT) was
successfully executed
this morning via Ops Request 18349. The test was completed
at 309/15:27.