NASA Hubble Space Telescope Daily Status Report #3857

DAILY REPORT       #3857

PERIOD COVERED: DOY 130

OBSERVATIONS SCHEDULED

ACS/WFC 10429

Streaming Towards Shapley: The Mass of the Richest Galaxy
Concentration in the Local Universe

The 600 km/s motion of the Local Group {LG} with respect to the cosmic
microwave background {CMB} is now known to high accuracy. However, its
precise origin remains poorly understood. The contribution to the
motion from the pull of the rich Shapley supercluster at z = 0.048 is
particularly controversial. This extreme mass concentration contains
more than 20 Abell clusters within 35 Mpc of its very rich central
cluster A3558, and is recognized as both the optically richest and the
most X-ray luminous structure in the local {z < 0.1} universe. Yet, published values for the mass of Shapley continue to differ by an order of magnitude, and recent estimates of its pull on the LG range from negligible {20 km/s} to highly significant {300 km/s or more}. Here we propose to resolve this key issue by using ACS to measure high- precision surface brightness fluctuation {SBF} distances in order to make a direct measurement of the infall towards Shapley. We will target three Shapley foreground clusters where the infall is expected to be high {possibly 1000 km/s or more}, as well as the Shapley core, in order to test the assumption that it is at rest in the CMB. Prior to ACS, the Shapley region was unreachable for SBF, but ACS doubles the distance range of the SBF method with HST, enabling the distances to be measured to the required accuracy. The proposed measurements will place a firm limit on the largest mass fluctuation in the nearby universe and finally determine its contribution to the observed CMB dipole.

ACS/WFC/WFPC2 10092

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
universe.

NIC1/NIC2/NIC3 8793

NICMOS Post-SAA calibration – CR Persistence Part 4

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 10177

Solar Systems In Formation: A NICMOS Coronagraphic Survey of
Protoplanetary and Debris Disks

Until recently, despite decades of concerted effort applied to
understanding the formation processes that gave birth to our solar
system, the detailed morphology of circumstellar material that must
eventually form planets has been virtually impossible to discern. The
advent of high contrast, coronagraphic imaging as implemented with the
instruments aboard HST has dramatically enhanced our understanding of
natal planetary system formation. Even so, only a handful of evolved
disks {~ 1 Myr and older} have been imaged and spatially resolved in
light scattered from their constituent grains. To elucidate the
physical processes and properties in potentially planet-forming
circumstellar disks, and to understand the nature and evolution of
their grains, a larger spatially resolved and photometrically reliable
sample of such systems must be observed. Thus, we propose a highly
sensitive circumstellar disk imaging survey of a well-defined and
carefully selected sample of YSOs {1-10 Myr T Tau and HAeBe stars} and
{> app 10 Myr} main sequence stars, to probe the posited epoch of
planetary system formation, and to provide this critically needed
imagery. Our resolved images will shed light on the spatial
distributions of the dust in these thermally emissive disks. In
combination with their long wavelength SEDs the physical properties of
the grains will be discerned, or constrained by our photometrically
accurate surface brightness sensitivity limits for faint disks which
elude detection. Our sample builds on the success of the exploratory
GTO 7233 program, using two-roll per orbit PSF- subtracted NICMOS
coronagraphy to provide the highest detection sensitivity to the
smallest disks around bright stars which can be imaged with HST. Our
sample will discriminate between proposed evolutionary scenarios while
providing a legacy of cataloged morphologies for interpreting mid- and
far-IR SEDs that the recently launched Spitzer Space Telescope will
deliver.

NIC3 10337

The COSMOS 2-Degree ACS Survey NICMOS Parallels

The COSMOS 2-Degree ACS Survey NICMOS Parallels. This program is a
companion to program 10092.

WFPC2 10360

WFPC2 CYCLE 13 INTERNAL MONITOR

This calibration proposal is the Cycle 13 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.

FLIGHT OPERATIONS SUMMARY:

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

HSTARS:

9806 – G_CoreData Server Grayed Out @ 130/15:00:00z CoreData Server
grayed out on G-String. Patrol Agent was found to be down. GDOC
restarted the Patrol Agent and cleared the problem.

9807 – GSAcq (2,1,1) requires multiple entries into CT @ 128/12:08:56z
OTA SE review of the PTAS processing found that the GSAcq(2,1,1) at
128/12:08:56 required 2 CT entries on FGS2 before achieving CT-DV. The
Acq was successful and no science impact should have been seen.

9808 – REACQ(1,2,2) scan step limit exceeded on FGS 1, acquisition
successful @ 131/05:52:49z REACQ(1,2,2) at 131/05:50:24 had scan step
limit exceeded on FGS 1 at 05:52:49. REACQ was successful on the
second attempt, no science affected.

COMPLETED OPS REQUEST: (None)

COMPLETED OPS NOTES:

1336-0 – Restore Some Thermal Limits @ 130/2229z

1337-0 – Modify TCS Limits @ 130/2235z

                           SCHEDULED     SUCCESSFUL    FAILURE TIMES 
 FGS Gsacq                06                      06 
 FGS Reacq                10                      10 
 FHST Update              10                      10 
 LOSS of LOCK 

SIGNIFICANT EVENTS:  (None)