HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science

 

DAILY REPORT       #4775

 

PERIOD COVERED: 5am January 21 - 5am January 22, 2009 (DOY

                           021/1000z-022/1000z)

 

OBSERVATIONS SCHEDULED

 

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.

 

FGS 11964

 

Post FGS1r AMA-Adjustment: OFAD Check and Alignment Calibration, 2008

 

The FGS1 AMA optimization proposal (11963) leaves the AMA mirror in a

new position, which shifts the FGS1r FOV relative to FGS2r and FGS3 and

has the potential to change the FGS1r OFAD solution. This proposal will

use the astrometric open cluster NGC 5617 to check for 1 mas size

changes in the OFAD and to establish the new alignment of FGS1r relative

to FGS2r and FGS3 to a precision of approximately 25 mas. The OFAD check

requires 4 HST orbits before, and 4 HST orbits after, the AMA

adjustment. Each orbit observes the same stars in NGC 5617 with FGS1r in

POS mode. The alignment aspect of this proposal uses data from these

same orbits. The ICRS positions of the relevant stars are taken from the

UCAC catalog, but the proper motions taken from the "special guide star

plate ZZZT" provided by Yale University. We chose guide stars in FGS2r

and FGS3, and astrometry targets that are common to GSC2, UCAC, and

ZZZT. Each visit uses a unique guide star pair, so that all the visits

taken together have guide stars spanning the guider FGSs FOV.

 

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 11130

 

AGNs with Intermediate-mass Black Holes: Testing the Black Hole-Bulge

Paradigm, Part II

 

The recent progress in the study of central black holes in galactic

nuclei has led to a general consensus that supermassive {10^6-10^9 solar

mass} black holes are closely connected with the formation and

evolutionary history of large galaxies, especially their bulge

component. Two outstanding issues, however, remain unresolved. Can

central black holes form in the absence of a bulge? And does the mass

function of central black holes extend below 10^6 solar masses?

Intermediate-mass black holes {<10^6 solar masses}, if they exist, may

offer important clues to the nature of the seeds of supermassive black

holes. Using the SDSS, our group has successfully uncovered a new

population of AGNs with intermediate-mass black holes that reside in

low-luminosity galaxies. However, very little is known about the

detailed morphologies or structural parameters of the host galaxies

themselves, including the crucial question of whether they have bulges

or not. Surprisingly, the majority of the targets of our Cycle 14 pilot

program have structural properties similar to dwarf elliptical galaxies.

The statistics from this initial study, however, are really too sparse

to reach definitive conclusions on this important new class of black

holes. We wish to extend this study to a larger sample, by using the

Snapshot mode to obtain WFPC2 F814W images from a parent sample of 175

AGNs with intermediate- mass black holes selected from our final SDSS

search. We are particularly keen to determine whether the hosts contain

bulges, and if so, how the fundamental plane properties of the host

depend on the mass of their central black holes. We will also

investigate the environment of this unique class of AGNs.

 

WFPC2 11944

 

Binaries at the Extremes of the H-R Diagram

 

We propose to use HST/Fine Guidance Sensor 1r to survey for binaries

among some of the most massive, least massive, and oldest stars in our

part of the Galaxy. FGS allows us to spatially resolve binary systems

that are too faint to observe using ground-based, speckle or optical

long baseline interferometry, and too close to resolve with AO. We

propose a SNAP-style program of single orbit FGS TRANS mode observations

of very massive stars in the cluster NGC 3603, luminous blue variables,

nearby low mass main sequence stars, cool subdwarf stars, and white

dwarfs. These observations will help us to (1) identify systems suitable

for follow up studies for mass determination, (2) study the role of

binaries in stellar birth and in advanced evolutionary states, (3)

explore the fundamental properties of stars near the main sequence-brown

dwarf boundary, (4) understand the role of binaries for X-ray bright

systems, (5) find binaries among ancient and nearby subdwarf stars, and

(6) help calibrate the white dwarf mass - radius relation.

 

WFPC2 11969

 

Satellite Search for Dawn Mission Targets, Vesta and Ceres

 

We propose to carry out a dedicated satellite search program for

asteroids Vesta and Ceres. Despite being the two largest asteroids, and

having clear evidence of a violent collisional history for Vesta, Vesta

and Ceres do not have any satellites found so far, neither have there

been any dedicated satellite search program for them reported. We

propose to take short and long exposure mosaics to cover the whole Hill

sphere while using specific observing strategies and image processing

techniques to search in close to the center body. In addition to its

significant scientific merit, this proposed project will be important

for the planning of NASA's Dawn mission. Currently Ceres is moving close

to the Earth, making it more difficult to cover the whole stability

region of satellites with minimal HST orbit requirement. Similar

geometry will not repeat until the second half of 2009. Therefore we

request DD time.

 

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                 11                  11                

FGS REacq                 0                    0                

OBAD with Maneuver  24                  24               

 

SIGNIFICANT EVENTS: (None)