HUBBLE SPACE TELESCOPE - Continuing to collect World Class
Science
DAILY REPORT #
4165
PERIOD COVERED: UT July 27, 2006 (DOY 208)
OBSERVATIONS SCHEDULED
ACS/HRC 10860
The largest Kuiper belt object
The past year has seen an explosion in the discoveries of
Pluto-sized
objects in the Kuiper belt. With the discoveries of the
methane-covered
2003 UB313 and 2005 FY9, the multiple satellite system of 2003 EL61,
and
the Pluto-Charon analog system of Orcus and its satellite, it is
finally
apparent that Pluto is not a unique oddball at the edge of the solar
system, but rather one of a family of similarly large objects in the
Kuiper belt and beyond. HST observations over the past decade have
been
critical for understanding the interior, surface, and atmosphere of
Pluto and Charon. We propose here a comprehensive series of
observations
designed to similarly expand our knowledge of these recently
discovered
Pluto-sized and near-Pluto-sized Kuiper belt objects. These
observations
will measure objects' sizes and densities, explore the outcome of
collisions in the outer solar system, and allow the first ever look
at
the interior structure of a Kuiper belt object. Our wide field
survey
that discovered all of these objects is nearly finished, so after
five
years of continuous searching we are finally almost complete in our
tally of these near-Pluto-sized objects. This large HST request is
the
culmination of this half-decade search for new planetary-sized
objects.
As has been demonstrated repeatedly by the approximately 100
previous
orbits devoted to the study of Pluto, only HST has the resolution
and
sensitivity for detailed study of these distant objects. With these
new
Pluto-sized objects only now being discovered we have a limited
window
left to still use HST for these critical observations.
ACS/WFC 10775
An ACS Survey of Galactic Globular Clusters
We propose to conduct an ACS/WFC imaging survey of Galactic globular
clusters. We will construct the most extensive and deepest set of
photometry and astrometry to-date for these systems reaching a main
sequence mass of ~0.2 solar mass with S/N >= 10. We will combine
these
data with archival WFPC2 and STIS images to determine proper motions
for
the stars in our fields. The resultant cleaned cluster CMDs will
allow
us to study a variety of scientific questions. These include [but
are
not limited to] 1} the determination of cluster ages and distances
2}
the construction of main sequence mass functions and the issue of
mass
segregation 3} the internal motions and dynamical evolution of
globular
clusters, and 4} absolute cluster motions, orbits, and the Milky Way
gravitational potential. We anticipate that the unique resource
provided
by the proposed treasury archive will play a central role in the
field
of globular cluster studies for decades, with a stature comparable
to
that of the Hubble Deep Field for high redshift studies.
ACS/WFC/NIC2 10496
Decelerating and Dustfree: Efficient Dark Energy Studies with
Supernovae
and Clusters
We propose a novel HST approach to obtain a dramatically more useful
"dust free" Type Ia supernovae {SNe Ia} dataset than available
with the
previous GOODS searches. Moreover, this approach provides a
strikingly
more efficient search-and-follow-up that is primarily pre-scheduled.
The
resulting dark energy measurements do not share the major systematic
uncertainty at these redshifts, that of the extinction correction with
a
prior. By targeting massive galaxy clusters at z > 1 we obtain a
five-times higher efficiency in detection of Type Ia supernovae in
ellipticals, providing a well-understood host galaxy environment.
These
same deep cluster images then also yield fundamental calibrations
required for future weak lensing and Sunyaev-Zel'dovich measurements
of
dark energy, as well as an entire program of cluster studies. The
data
will make possible a factor of two improvement on supernova
constraints
on dark energy time variation, and much larger improvement in
systematic
uncertainty. They will provide both a cluster dataset and a SN Ia
dataset that will be a longstanding scientific resource.
NIC1 10879
A search for planetary-mass companions to the nearest L dwarfs -
completing the survey
We propose to extend the most sensitive survey yet undertaken for
very
low-mass companions to ultracool dwarfs. We will use NICMOS to
complete
imaging of an all-sky sample of 87 L dwarfs in 80 systems within 20
parsecs of the Sun. The combination of infrared imaging and
proximity
allows us to search for companions with mass ratios q>0.25 at
separations exceeding ~3 AU, while probing companions with q>0.5 at
~1.5
AU separation. This resolution is crucial, since no ultracool
binaries
are known in the field with separations exceeding 15 AU. Fifty L
dwarfs
from the 20-parsec sample have high- resolution imaging, primarily
through our Cycle 13 HST proposal which identified six new binaries,
including an L/T system. Here, we propose to target the remaining 30
dwarfs
NIC1 10889
The Nature of the Halos and Thick Disks of Spiral Galaxies
We propose to resolve the extra-planar stellar populations of the
thick
disks and halos of seven nearby, massive, edge-on galaxies using
ACS,
NICMOS, and WFPC2 in parallel. These observations will provide
accurate
star counts and color-magnitude diagrams 1.5 magnitudes below the tip
of
the Red Giant Branch sampled along the two principal axes and one
intermediate axis of each galaxy. We will measure the metallicity
distribution functions and stellar density profiles from star counts
down to very low average surface brightnesses, equivalent to ~32
V-mag
per square arcsec. These observations will provide the definitive
HST
study of extra-planar stellar populations of spiral galaxies. Our
targets cover a range in galaxy mass, luminosity, and morphology and
as
function of these galaxy properties we will provide: - The first
systematic study of the radial and isophotal shapes of the diffuse
stellar halos of spiral galaxies - The most detailed comparative
study
to date of thick disk morphologies and stellar populations - A
comprehensive analysis of halo and thick disk metallicity
distributions
as a function of galaxy type and position within the galaxy. - A
sensitive search for tidal streams - The first opportunity to
directly
relate globular cluster systems to their field stellar population We
will use these fossil records of the galaxy assembly process
preserved
in the old stellar populations to test halo and thick disk formation
models within the hierarchical galaxy formation scheme. We will test
LambdaCDM predictions on sub-galactic scales, where it is difficult
to
test using CMB and galaxy redshift surveys, and where it faces its
most
serious difficulties.
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 10527
Imaging Scattered Light from Debris Disks Discovered by the Spitzer
Space Telescope Around 20 Sun-like Stars
We propose to use the high contrast capability of the NICMOS
coronagraph
to image a sample of newly discovered circumstellar disks associated
with sun-like stars. These systems were identified by their strong
thermal infrared emission with the Spitzer Space Telescope as part
of
the Spitzer Legacy Science program titled, "The Formation and
Evolution
of Planetary Systems {FEPS}." Modelling of the thermal excess
emission
in the form of spectral energy distributions alone cannot
distinguish
between narrowly confined high opacity disks and broadly
distributed,
low opacity disks. However, our proposed NICMOS observations can, by
imaging the light scattered from this material. Even non- detections
will place severe constraints on the disk geometry, ruling out
models
with high optical depth. Unlike previous disk imaging programs, our
program contains a well defined sample of solar mass stars covering
a
range of ages from ~10Myrs to a few Gyrs, allowing us to study the
evolution of disks from primordial to debris for the first time.
These
results will greatly improve our understanding of debris disks
around
Sun-like stars at stellar ages nearly 10x older than any previous
investigation. Thus we will have fit a crucial piece into the puzzle
concerning the formation and evolution of our own solar system.
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:
#17864-0 Execute ROP NS-11 (Reset NICMOS Error Counter)
@208/1337z
COMPLETED OPS NOTES: (None)
SCHEDULED SUCCESSFUL
FGS
GSacq
06 06
FGS
REacq
10
10
OBAD with Maneuver
30 30
SIGNIFICANT EVENTS: (None)
-Lynn
Lynn F. Bassford
CHAMP HST Missions Operations Manager
Lockheed Martin Technical Operations
GSFC PH#: 301-286-2876
Cell/Voice Mail: 240-603-4873 Text/Pager:
2406034873@messaging.sprintpcs.com
"The Hubble Space Telescope is the astronomical observatory and
key to unlocking the most cosmic mysteries of the past, present and
future." - 7/26/6
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