HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science

DAILY REPORT       #4685

PERIOD COVERED: 5am August 28 - 5am August 29, 2008 (DOY 241/0900z-242/0900z)

OBSERVATIONS SCHEDULED

FGS 11210

The Architecture of Exoplanetary Systems

Are all planetary systems coplanar? Concordance cosmogony makes that

prediction. It is, however, a prediction of extrasolar planetary system

architecture as yet untested by direct observation for main sequence

stars other than the Sun. To provide such a test, we propose to carry

out FGS astrometric studies on four stars hosting seven companions. Our

understanding of the planet formation process will grow as we match not

only system architecture, but formed planet mass and true distance from

the primary with host star characteristics for a wide variety of host

stars and exoplanet masses. We propose that a series of FGS astrometric

observations with demonstrated 1 millisecond of arc per-observation

precision can establish the degree of coplanarity and component true

masses for four extrasolar systems: HD 202206 {brown dwarf+planet}; HD

128311 {planet+planet}, HD 160691 = mu Arae {planet+planet}, and HD

222404AB = gamma Cephei {planet+star}. In each case the companion is

identified as such by assuming that the minimum mass is the actual mass.

For the last target, a known stellar binary system, the companion orbit

is stable only if coplanar with the AB binary orbit.

NIC1 11205

The Effects of Multiplicity on the Evolution of Young Stellar Objects: A

NICMOS Imaging Study

We propose to use NICMOS to investigate the multiplicity of young

stellar objects (YSOs) in the Orion B molecular cloud. Previous

observations with the Spitzer Space Telescope have revealed a remarkable

star forming filament near the NGC 2068 reflection nebula. The

population of YSOs associated with the filament exhibit a surprisingly

wide range of circumstellar evolutionary states, from deeply embedded

protostars to T Tauri accretion disks. Many of the circumstellar disks

themselves show evidence for significant dust evolution, including grain

growth and settling and cleared inner holes, apparently in spite of the

very young age of these stars. We will estimate the binary fraction of a

representative sample of objects in these various stages of evolution in

order to test whether companions may play a significant role in that

evolution.

NIC1/NIC2/NIC3 11820

NICMOS Post-SAA Calibration - CR Persistence Part 7

Internals for CR persistence

NIC2 11237

The Origin of the Break in the AGN Luminosity Function

We propose to use NICMOS imaging to measure rest-frame optical

luminosities and morphological properties of a complete sample of faint

AGN host galaxies at redshifts z ~ 1.4. The targets are drawn from the

VLT-VIMOS Deep Survey, and they constitute a sample of the lowest

luminosity type 1 AGN known at z > 1. The spectroscopically estimated

black hole masses are up to an order of magnitude higher than expected

given their nuclear luminosities, implying highly sub-Eddington

accretion rates. This exactly matches the prediction made by recent

theoretical models of AGN evolution, according to which the faint end of

the AGN luminosity function is populated mainly by big black holes that

have already exhausted a good part of their fuel. In this proposal we

want to test further predictions of that hypothesis, by focusing on the

host galaxy properties of our low-luminosity, low- accretion AGN. If the

local ratio between black hole and bulge masses holds at least

approximately at these redshifts, one expects most of these

low-luminosity AGN to reside in fairly big ellipticals with stellar

masses around and above 10^11 solar masses (in contrast to the Seyfert

phenomenon in the local universe). With NICMOS imaging we will find out

whether that is true, implying also a sensitive test for the validity of

the M_BH/M_bulge relation at z ~ 1.4.

NIC2 11548

NICMOS Imaging of Protostars in the Orion A Cloud: The Role of

Environment in Star Formation

We propose NICMOS observations of a sample of 252 protostars identified

in the Orion A cloud with the Spitzer Space Telescope. These

observations will image the scattered light escaping the protostellar

envelopes, providing information on the shapes of outflow cavities, the

inclinations of the protostars, and the overall morphologies of the

envelopes. In addition, we ask for Spitzer time to obtain 55-95 micron

spectra of 75 of the protostars. Combining these new data with existing

3.6 to 70 micron photometry and forthcoming 5-40 micron spectra measured

with the Spitzer Space Telescope, we will determine the physical

properties of the protostars such as envelope density, luminosity,

infall rate, and outflow cavity opening angle. By examining how these

properties vary with stellar density (i.e. clusters vs groups vs

isolation) and the properties of the surrounding molecular cloud; we can

directly measure how the surrounding environment influences protostellar

evolution, and consequently, the formation of stars and planetary

systems. Ultimately, this data will guide the development of a theory of

protostellar evolution.

WFPC2 11113

Binaries in the Kuiper Belt: Probes of Solar System Formation and

Evolution

The discovery of binaries in the Kuiper Belt and related small body

populations is powering a revolutionary step forward in the study of

this remote region. Three quarters of the known binaries in the Kuiper

Belt have been discovered with HST, most by our snapshot surveys. The

statistics derived from this work are beginning to yield surprising and

unexpected results. We have found a strong concentration of binaries

among low-inclination Classicals, a possible size cutoff to binaries

among the Centaurs, an apparent preference for nearly equal mass

binaries, and a strong increase in the number of binaries at small

separations. We propose to continue this successful program in Cycle 16;

we expect to discover at least 13 new binary systems, targeted to

subgroups where these discoveries can have the greatest impact.

WFPC2 11544

The Dynamical Legacy of Star Formation

We propose to use WFPC2 to conduct a wide-field imaging survey of the

young cluster IC348. This program, in combination with archival HST

observations, will allow us to measure precise proper motions for

individual cluster members, characterizing the intra-cluster velocity

dispersion and directly studying the dynamical signatures of star

formation and early cluster evolution. Our projected astrometric

precision (~1 mas in each epoch) will allow us to calculate individual

stellar velocities to unprecedented precision (<0.5 mas/yr; <1 km/s) and

directly relate these velocities to observed spatial substructure within

the cluster. This survey will also allow us to probe small-scale star

formation physics by searching for high-velocity stars ejected from

decaying multiple systems, expanding our knowledge of multiplicity in

dense environments, and identifying new substellar and planetary-mass

cluster members based on kinematic membership tests.

WFPC2 11795

WFPC2 Cycle 16 UV Earth Flats

Monitor flat field stability. This proposal obtains sequences of earth

streak flats to improve the quality of pipeline flat fields for the

WFPC2 UV filter set. These Earth flats will complement the UV earth flat

data obtained during cycles 8-15.

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: (None)

COMPLETED OPS NOTES: (None)

                        SCHEDULED      SUCCESSFUL

FGS GSacq                08                 08               

FGS REacq                07                 07               

OBAD with Maneuver 30                  30              

SIGNIFICANT EVENTS: (None)