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 # 4359
PERIOD COVERED: UT May 09, 2007 (DOY 129)
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 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 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 11085
Europa in Eclipse: Tenuous Atmosphere, Electromagnetic
Activity and
Surface Luminescence HST Proposal 11085
We propose to image Europa during its orbital eclipse by
Jupiter. This
will form the basis of an investigation into the nature of
the tenuous
atmosphere, electromagnetic environment and surface
material of Europa.
We will compare the FUV oxygen line at 1356A to the
optical line at
6300A and seek optical auroral hydrogen emission in
Halpha. With broad
continuum filters, we will search for optical emissions
from other
atmospheric constituents and for fluorescence of the
surface material,
arising from the very high level of incident energetic
particle
radiation. The high spatial resolution of ACS will allow
us to fully
resolve scales of interest and allow us to distinguish
easily the
different terrains on Europa's surface. In particular we
wish to compare
luminesence in regions dominated by ice to those of
potentially organic
red material.
FLIGHT OPERATIONS SUMMARY:
Significant Spacecraft Anomalies: (The following are
preliminary reports
of potential non-nominal performance that will be
investigated.)
HSTARS:
10804 - FHST OBAD Failure
At AOS 130/05:07:49 OBAD #2 scheduled @ 130/04:40:15 had
failed.
OBAD #1: Data unavailable due to LOS
OBAD #2: V1 31234.84, V2 -9674.28, V3 12657.23, RSS
35062.98
COMPLETED OPS REQUEST:
18077-2 - MSS/CSS Converged & Add Gyro1 input Test #34
18070-5 - MSS/CSS Add Gyro2 input Test #38 for SMS 127
18073-1 - PCS KF OOT Support
18054-0 - Preview KF Sun Vector Data via Telemetry Diags
17543-2 - Dump OBAD tables after failed OBAD (Generic)
COMPLETED OPS NOTES: (None)
SCHEDULED
SUCCESSFUL
FGS GSacq
11
11
FGS REacq
03
03
OBAD with Maneuver
28
27
SIGNIFICANT EVENTS:
Evaluation of Universal Kalman Filter performance
continued. Multiple
text segments were executed, all of them successfully.
Details follow.
Background Kalman Filter Operation Flash Report for day
129:
The KF was halted at 129/14:38. The filter was restarted
at
129/14:41 during orbit day and during an M2G guiding
interval. The
filter was activated with the MSS and Gyro1 sensor inputs
enabled. The
Gyro1 sensor input was removed from the converged filter
at 16:22 during
orbit day, in an M2G guiding interval with the vehicle
inertially fixed
and during a slow changing B-field. All UKF parameters
showed nominal
operation. The test was an MSS/CSS test case with the
Gyro1 sensor input
removed during a slow changing B-field and with the
spacecraft
inertially fixed (MC_G1_HNS, Test #34).
The removal of the Gyro1 input
configured the KF back to the desired KF configuration for
this week.
The activity above used the slot 1 TMDIAG at 129/16:21.
The slot 1
TMDIAG was reset to monitor the V2 component of the KF
estimated sun
vector at 129/19:09.
The KF was halted at 129/17:20. The filter was restarted
at
129/17:22 during orbit night and during an F2G guiding
interval. The
filter was activated with the MSS and CSS input enabled.
The Gyro1
sensor input was added to the converged filter at 18:05
during orbit
day, during a vehicle maneuver, during an M2G guiding
interval and
during a slow changing B-field. All UKF parameters showed
nominal
operation. The test was an MSS/CSS test case with the
Gyro1 sensor input
added during a slow changing B-field and during a vehicle
maneuver
(MC_G1_RVS, Test #28). The MSS only configuration of the
KF was restored
at 129/19:08.