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.