HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science

DAILY REPORT      #4776

PERIOD COVERED: 5am January 22 - 5am January 23, 2009 (DOY

                           022/1000z-023/1000z)

OBSERVATIONS SCHEDULED

FGS 11963

FGS1r AMA Re-Optimization

This proposal re-optimizes FGS1r interferometric performance (S-curves)

by adjustment of the instrument's AMA. This will improve the FGS1r

angular resolution in Transfer Mode while improving the reliability of

Position Mode observations. Observations of close binaries (separations

ranging from 12 to 20 mas) and all stars fainter than V=15 will benefit

from this re-optimization. Moreover, this re-optimization will return

FGS1r to the commissioning state that was deemed optimal for operating

it as a guider in 1997.

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 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 11956

Hubble Heritage: Side B

We propose a program of 39 orbits to observe 6 targets with WFPC2

following a successful return to science using side B electronics. These

observations will be used for Hubble Heritage releases in the months

leading up to servicing mission 4. Because of launch delays, our reserve

of releasable images is growing dangerously slim. We are proposing here

to replenish one of our important lines of communication with the

public.

We have carefully chosen targets that can efficiently use single

pointings of WFPC2 to obtain images of visually striking and

astrophysically interesting targets. Observations will reach high S/N

and will be dithered and subsampled to improve the resolution and pixel

scale to near ACS/WFC3 quality at a modest cost in exposure time. Most

of the observations will schedule in the interim between a return to

science and the availability of new science proposals that may be

selected in response to an interim call for proposals.

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               09                  09                

FGS REacq                01                 01                

OBAD with Maneuver 24                  24               

SIGNIFICANT EVENTS:

Flash Report:

The FGS1R AMA move and associated change of the Coarse Mode Angle check

threshold was completed at 2009.022/13:17 UTC.