Notice: For the foreseeable future, the daily reports may
contain
apparent discrepancies between some proposal descriptions
and the listed
instrument usage. This is due to the conversion of
previously approved
ACS WFC or HRC observations into WFPC2, or NICMOS
observations
subsequent to the loss of ACS CCD science capability in
late January.
HUBBLE SPACE TELESCOPE - Continuing to collect World Class
Science
DAILY REPORT # 4360
PERIOD COVERED: UT May 10, 2007 (DOY 130)
OBSERVATIONS SCHEDULED
WFPC2 10800
Kuiper Belt Binaries: Probes of Early Solar System
Evolution
Binaries in the Kuiper Belt are a scientific windfall: in
them we have
relatively fragile test particles which can be used as
tracers of the
early dynamical evolution of the outer Solar System. We
propose to
continue a Snapshot program using the ACS/HRC that has a
demonstrated
discovery potential an order of magnitude higher than the
HST
observations that have already discovered the majority of
known
transneptunian binaries. With this continuation we seek to
reach the
original goals of this project: to accumulate a
sufficiently large
sample in each of the distinct populations collected in
the Kuiper Belt
to be able to measure, with statistical significance, how
the fraction
of binaries varies as a function of their particular
dynamical paths
into the Kuiper Belt. Today's Kuiper Belt bears the imprints
of the
final stages of giant-planet building and migration;
binaries may offer
some of the best preserved evidence of that long-ago era.
NIC1 11057
Cycle 15 NICMOS dark current, shading profile, and read
noise monitoring
program
The purpose of this proposal is to monitor the dark
current, read noise,
and shading profile for all three NICMOS detectors
throughout the
duration of Cycle 15. This proposal is a slightly modified
version of
proposal 10380 of cycle 13 and 9993 of cycle12 and is the
same as Cycle
14. that we cut down some exposure time to make the
observation fit
within 24 orbits.
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 10849
Imaging Scattered Light from Debris Disks Discovered by
the Spitzer
Space Telescope around 21 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 {IR} emission with the Spitzer Space
Telescope as part
of the Spitzer Legacy Science program titled "The
Formation and
Evolution of Planetary Systems" {FEPS, P.I.:
M.Meyer}. Modeling of the
thermal excess emission from the spectral energy
distributions alone
cannot distinguish between narrowly confined high-opacity
disks and
broadly distributed, low-opacity disks. By resolving light
scattered by
the circumstellar material, our proposed NICMOS
observations can break
this degeneracy, thus revealing the conditions under which
planet
formation processes are occuring or have occured. For
three of our
IR-excess stars that have known radial-velocity planets,
resolved
imaging of the circumstellar debris disks may further
offer an
unprecedented view of planet-disk interactions in an
extrasolar
planetary system. Even non-detections of the light
scattered by the
circumstellar material will place strong constraints on
the disk
geometries, ruling out disk models with high optical
depth. Unlike
previous disk imaging programs, our program contains a
well-defined
sample of ~1 solar mass stars covering a range of ages
from 3 Myr to 3
Gyr, thus allowing us to study the evolution of disks from
primordial to
debris for the first time. The results from our program
will greatly
improve our understanding of the architecture of debris
disks around
Sun-like stars, and will create a morphological context
for the
existence of our own solar system. This proposal is for a
continuation
of an approved Cycle 14 program {GO/10527, P.I.: D.
Hines}.
NIC2 10857
Are Organics Common in Outer Planetary Systems?
Mixtures of water ice and organics seem to pervade
surfaces in the outer
Solar System, from the rings of Saturn to the Kuiper Belt
Objects. The
early Earth was bombarded by the leftover planetesimals
from the
formation of the planets, and these must have been rich in
both ice and
carbon to provide the building blocks of life. Scattered
light from
debris disks is remarkably similar in albedo {total
scattering
efficiency} and color {red} to the objects in the outer
solar system.
Thus, we have a hint that the same photochemical processes
that happened
close to home also happen around other stars. We propose
to study the
color of two debris disks in some detail. Scattering of
light is the
only window available to us to see the composition of
debris disks in a
spatially resolved manner and to assess their potential
for containing
planets like ours.
WFPC2 10903
Resolving the LMC Microlensing Puzzle: Where are the
Lensing Objects?
We are requesting 12 HST orbits to continue to investigate
the nature of
the population that gives rise to the microlensing seen
towards the LMC.
This proposal builds on the cycle 14 HST program {10583}
and will
complement the study with 12 yet-to-be discovered
microlensing
candidates from Fall 2006. Our SuperMacho project is an
ongoing ground-
based survey on the CTIO 4m that has demonstrated the
ability to detect
LMC microlensing events via frame subtraction. The
combination of high
angular resolution and photometric accuracy with HST will
allow us to 1}
confrim that the detected flux excursions arise from LMC
stars, rather
than background supernovae or AGN, and 2} obtain reliable
baseline flux
measurements for the objects in their unlensed state. This
latter
measurement in important in determining the microlensing
optical depth
towards the LMC.
FLIGHT OPERATIONS SUMMARY:
Significant Spacecraft Anomalies: (The following are
preliminary reports
of potential non-nominal performance that will be
investigated.)
HSTARS:
10805 - REacq(2,3,2) failed due to scan step limit
exceeded
The REacq(2,3,2) scheduled at 130/13:58:51 failed due to scan step limit
exceeded on FGS 2. OBAD 2 before the REaqc showed errors of V1=1.59,
V2=1.34, V3=9.72, and RSS=9.94.
COMPLETED OPS REQUEST: (None)
COMPLETED OPS NOTES: (None)
SCHEDULED
SUCCESSFUL
FGS GSacq
09
09
FGS REacq
05
04
OBAD with Maneuver
28
28
SIGNIFICANT EVENTS:
Evaluation of Universal Kalman Filter performance
continued. Details
follow.
Flash Report: Background Kalman Filter Operation,
Day 130
A Kalman filter performance test was executed from
130/16:10 to 16:55
per Ops Request 18071-3. The KF was initialized with CSS
and MSS inputs
enabled at 130/16:10. Gyro 2 input to the KF was enabled
at 16:28:30
under slow-changing B-field conditions during an M2G
vehicle maneuver.
Gyro 2 input to the KF was disabled at 16:40 and CSS input
was disabled
at 16:52, returning the KF to the pre-test MSS-only
configuration.
Kalman filter convergence and operation during the test
was nominal.