Daily Report #4377

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 # 4377

PERIOD COVERED: UT June 05, 2007 (DOY 156)

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.

WFPC2 10877

A Snapshot Survey of the Sites of Recent, Nearby Supernovae

During the past few years, robotic {or nearly robotic} searches for
supernovae {SNe}, most notably our Lick Observatory Supernova Search {LOSS},
have found hundreds of SNe, many of them in quite nearby galaxies {cz 4000
km/s}. Most of the objects were discovered before maximum brightness, and
have follow-up photometry and spectroscopy; they include some of the
best-studied SNe to date. We propose to conduct a snapshot imaging survey of
the sites of some of these nearby objects, to obtain late-time photometry
that {through the shape of the light and color curves} will help reveal the
origin of their lingering energy. The images will also provide
high-resolution information on the local environments of SNe that are far
superior to what we can procure from the ground. For example, we will obtain
color-color and color-magnitude diagrams of stars in these SN sites, to
determine the SN progenitor masses and constraints on the reddening.
Recovery of the SNe in the new HST images will also allow us to actually
pinpoint their progenitor stars in cases where pre- explosion images exist
in the HST archive. This proposal is an extension of our successful Cycle 13
snapshot survey with ACS. It is complementary to our Cycle 15 archival
proposal, which is a continuation of our long-standing program to use
existing HST images to glean information about SN environments.

ACS/SBC 10862

Comprehensive Auroral Imaging of Jupiter and Saturn during the International
Heliophysical Year

A comprehensive set of observations of the auroral emissions from Jupiter
and Saturn is proposed for the International Heliophysical Year in 2007, a
unique period of especially concentrated measurements of space physics
phenomena throughout the solar system. We propose to determine the physical
relationship of the various auroral processes at Jupiter and Saturn with
conditions in the solar wind at each planet. This can be accomplished with
campaigns of observations, with a sampling interval not to exceed one day,
covering at least one solar rotation. The solar wind plasma density
approaching Jupiter will be measured by the New Horizons spacecraft, and a
separate campaign near opposition in May 2007 will determine the effect of
large-scale variations in the interplanetary magnetic field {IMF} on the
Jovian aurora by extrapolation from near-Earth solar wind measurements. A
similar Saturn campaign near opposition in Jan. 2007 will combine
extrapolated solar wind data with measurements from a wide range of
locations within the Saturn magnetosphere by Cassini. In the course of
making these observations, it will be possible to fully map the auroral
footprints of Io and the other satellites to determine both the local
magnetic field geometry and the controlling factors in the electromagnetic
interaction of each satellite with the corotating magnetic field and plasma
density. Also in the course of making these observations, the auroral
emission properties will be compared with the properties of the near-IR
ionospheric emissions {from ground-based observations} and non thermal radio
emissions, from ground-based observations for Jupiter?s decametric radiation
and Cassini plasma wave measurements of the Saturn Kilometric Radiation
{SKR}.

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 11157

NICMOS Imaging Survey of Dusty Debris Around Nearby Stars Across the Stellar
Mass Spectrum

Association of planetary systems with dusty debris disks is now quite
secure, and advances in our understanding of planet formation and evolution
can be achieved by the identification and characterization of an ensemble of
debris disks orbiting a range of central stars with different masses and
ages. Imaging debris disks in starlight scattered by dust grains remains
technically challenging so that only about a dozen systems have thus far
been imaged. A further advance in this field needs an increased number of
imaged debris disks. However, the technical challege of such observations,
even with the superb combination of HST and NICMOS, requires the best
targets. Recent HST imaging investigations of debris disks were
sample-limited not limited by the technology used. We performed a search for
debris disks from a IRAS/Hipparcos cross correlation which involved an
exhaustive background contamination check to weed out false excess stars.
Out of ~140 identified debris disks, we selected 22 best targets in terms of
dust optical depth and disk angular size. Our target sample represents the
best currently available target set in terms of both disk brightness and
resolvability. For example, our targets have higher dust optical depth, in
general, than newly identified Spitzer disks. Also, our targets cover a
wider range of central star ages and masses than previous debris disk
surveys. This will help us to investigate planetary system formation and
evolution across the stellar mass spectrum. The technical feasibility of
this program in two-gyro mode guiding has been proven with on- orbit
calibration and science observations during HST cycles 13, 14, and 15.

NIC3 11080

Exploring the Scaling Laws of Star Formation

As a variety of surveys of the local and distant Universe are approaching a
full census of galaxy populations, our attention needs to turn towards
understanding and quantifying the physical mechanisms that trigger and
regulate the large-scale star formation rates {SFRs} in galaxies.

WFPC2 11310

Jupiter's North Temperate Belt Disturbance

A unique and huge disturbance started at the end of March 2007 in the
strongest Jovian atmospheric jet at 24deg N with the eruption of two bright
plumes followed by a dark albedo turbulent pattern which fully changed the
jet structure and the belt/zone pattern at this latitude. This kind of
disturbance is rare in Jupiter, the last one was observed in 1990 but only
at low resolution. Up to now we have studied the 2007 event using a battery
of ground- based instrumentation {with visible and infrared wavelength
coverage}, and after 40 days of development, the two plumes have
extinguished whereas the disturbance has fully encircled the planet, forming
a new dark belt. We have HST WFPC2 high resolution images of the belt/jet
structure at 24deg N before the eruption. Those images were taken in January
and February 2007 to support the New Horizons flyby, and now we require new
observations of the new belt and jet following the disturbance, to compare
both stages and determine its action on the jet wind profile and belt/zone
cloud vertical structure. This comparison will provide for the first time
valuable information on the maintenance, variability and origin of Jupiter
jets and cloud banding.

FLIGHT OPERATIONS SUMMARY:

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

HSTARS:

10850 - OBAD Failed Identification

At AOS 157/07:16:31 OBAD ID & TxG FHST Sanity Check Failed. OBAD2 & GSAcq
were successful. OBAD MAP errors: V1 -2.92, V2 -8.85, V3 -0.41, RSS 9.33.

COMPLETED OPS REQUEST: (None)

COMPLETED OPS NOTES: (None)

SCHEDULED SUCCESSFUL

FGS GSacq 09 09
FGS REacq 03 03
OBAD with Maneuver 24 23

SIGNIFICANT EVENTS: (None)