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    # 4384

 

PERIOD COVERED: UT June 14, 2007 (DOY 165)

 

OBSERVATIONS SCHEDULED

 

FGS 10927

 

The Weight-Watcher Program for Subdwarfs

 

We propose to use HST/FGS1r to measure five subdwarf spectroscopic

binaries to determine masses for the components. Their metallicities,

[Fe/H], range from -0.5 to -2.5, and their projected minimum separations

range from 9 to 24 mas. These binaries are resolvable with HST/FGS1r but

not any ground-based technique. Currently, there are only two subdwarf

systems having any mass measurements. The proposed work will boost the

total number of subdwarf systems with masses from two to seven, and

allow us to construct the first mass-luminosity relation for

low-metallicity stars.

 

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.

 

NIC3 10996

 

NICMOS J-band Imaging of Strongly Lensing Clusters

 

We propose to use deep imaging in the F110W {'J'} band over a large area

to search for highly magnified galaxies around massive lensing clusters.

 

WFPC2 10818

 

Very Young Globular Clusters in M31 ?

 

We propose to use HST's unique high spatial resolution imaging

capabilities to conclusively confirm or refute the presence of alleged

very young globular clusters in M31. Such young globular clusters with

ages < 3 Gyr are not present in our galaxy, and, if real, would lead to

a striking difference in the age distribution of the GCs between M31 and

the Millky Way. If the apparent presence of very young globular clusters

in M31 is confirmed through our proposed ACS imaging {now WFPC2 imaging}

with HST, this would suggest major differences in the history of

assembly of the two galaxies, with probable substantial late accretion

into M31 which did not occur in our own galaxy.

 

WFPC2 11084

 

Probing the Least Luminous Galaxies in the Local Universe

 

We propose to obtain deep color-magnitude data of eight new Local Group

galaxies which we recently discovered: Andromeda XI, Andromeda XII, and

Andromeda XIII {satellites of M31}; Canes Venatici I, Canes Venatici II,

Hercules, and Leo IV {satellites of the Milky Way}; and Leo T, a new

"free-floating" Local Group dwarf spheroidal with evidence for recent

star formation and associated H I gas. These represent the least

luminous galaxies known at *any* redshift, and are the only accessible

laboratories for studying this extreme regime of galaxy formation. With

deep WFPC-2 F606W and F814W pointings at their centers, we will

determine whether these objects contain single or multiple age stellar

populations, as well as whether these objects display a range of

metallicities.

 

FLIGHT OPERATIONS SUMMARY:

 

Significant Spacecraft Anomalies: (The following are preliminary reports

of potential non-nominal performance that will be investigated.)

 

HSTARS: 10862 – GSacq(2,1,1) failed to RGA control.

GSacq(2,1,1) scheduled at 166/05:12:52 failed at 05:16:35 due to scan

step limit exceeded on FGS 2. OBAD1 showed errors of V1=-433.76,

V2=-3218.95, V3=691.56,and RSS= 3320.85. OBAD2 showed errors of

V1=-2.74, V2=-10.01, V3=9.53, and RSS= 14.09. the map at 05:20:22 showed

errors of V1=-0.61, V2=7.16, V3=3.43, and RSS = 7.96.

 

COMPLETED OPS REQUEST: (None)

 

 

                             SCHEDULED      SUCCESSFUL    

FGS GSacq                    8                     7                              

FGS REacq                    6                     6                 

OBAD with Maneuver    28                    28                   

 

 

COMPLETED OPS NOTES: (None)

 

SIGNIFICANT EVENTS: (None)