Daily Report #4658

HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science

DAILY REPORT*** #4658

PERIOD COVERED: 5am July 22 - 5am July 23, 2008 (DOY
204/0900z-205/0900z)

OBSERVATIONS SCHEDULED

FGS 11212

Filling the Period Gap for Massive Binaries

The current census of binaries among the massive O-type stars is
seriously incomplete for systems in the period range from years to
millennia because the radial velocity variations are too small and the
angular separations too close for easy detection. Here we propose to
discover binaries in this observational gap through a Faint Guidance
Sensor SNAP survey of relatively bright targets listed in the Galactic
O Star Catalog. Our primary goal is to determine the binary frequency
among those in the cluster/association, field, and runaway groups. The
results will help us assess the role of binaries in massive star
formation and in the processes that lead to the ejection of massive
stars from their natal clusters. The program will also lead to the
identification of new, close binaries that will be targets of long
term spectroscopic and high angular resolution observations to
determine their masses and distances. The results will also be
important for the interpretation of the spectra of suspected and newly
identified binary and multiple systems.

NIC1/NIC2/NIC3 8795

NICMOS Post-SAA Calibration - CR Persistence Part 6

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 i mages. Each observation will need its
own CRMAP, as different SAA passages leave different imprints on the
NICMOS detectors.

NIC2 11135

Extreme Makeovers: Tracing the Transformation of Massive Galaxies at
z~2.5

To obtain a full spectroscopic census of the universe at z~2.5 we have
conducted a near-infrared spectroscopic survey for K-selected
galaxies. We found that, in contrast to the local universe, massive
high-redshift galaxies span a wide range of properties, varying from
(dusty) star burst to "red and dead" galaxies. This may imply that
massive galaxies transform from star-forming to quiescent galaxies in
the targeted redshift range. To understand whether the 9 quiescent
galaxies in our sample are the progenitors of local elliptical, we are
observing them in the current cycle with NIC2. For cycle 16 we propose
to complete our sample of massive z~2.5 galaxies and image the
remaining 10 galaxies, which all have emission lines. Based on
emission-line diagnostics, 6 of these galaxies are identified as
star-forming objects and 4 harbor an active galactic nucleus. The
goals are to 1) determine whether star formation in massive z~2.5
galaxies takes place in disks or is triggered by merger activity, 2)
derive the contribution of AGNs to the rest-frame optical emission,
and 3) test whether the morphologies are consistent with the idea that
the star-forming galaxies, AGNs, and quiescent galaxies represent
subsequent phases of an evolutionary sequence. The combination of both
programs will provide the first morphological study of a
spectroscopically confirmed massive galaxy sample at z~2.5.

NIC3 11545

A NICMOS Survey of Newly-Discovered Young Massive Clusters

We are on the cusp of a revolution in massive star research triggered
by 2MASS and Spitzer/GLIMPSE, and now is the ideal time to capitalize
on these projects by performing the first survey of massive stars in
young stellar clusters throughout the Galactic plane. A search of the
2MASS and GLIMPSE surveys has produced over 450 newly-identified
massive stellar cluster candidates in the Galactic plane which are
hidden from our view at optical wavelengths due to extinction. Here we
propose a program of 29 orbits to image the most promising candidate
clusters in broad and narrow band filters using HST/NICMOS. We will be
complementing these observations with approved Spitzer and Chandra
programs, numerous approved and planned ground-based spectroscopic
observations, and state-of-the-art modeling. We expect to
substantially increase the numbers of massive stars known in the
Galaxy, including main sequence OB stars and post-main sequence stars
in the Red Supergiant, Luminous Blue Variable and Wolf-Rayet stages.
Ultimately, this program will address many of the fundamental topics
in astrophysics: the slope to the initial mass function (IMF), an
upper-limit to the masses of stars, the formation and evolution of the
most massive stars, gamma-ray burst (GRB) progenitors, the chemical
enrichment of the interstellar medium, and nature of the first stars
in the Universe.

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 11156

Monitoring Active Atmospheres on Uranus and Neptune

We propose Snapshot observations of Uranus and Neptune to monitor
changes in their atmospheres on time scales of weeks and months.
Uranus equinox is only months away, in December 2007. Hubble Space
Telescope observations during the past several years {Hammel et al.
2005, Icarus 175, 284 and references therein} have revealed strongly
wavelength- dependent latitudinal structure, the presence of numerous
visible-wavelength cloud features in the northern hemisphere, at least
one very long-lived discrete cloud in the southern hemisphere, and in
2006 the first dark spot ever seen on Uranus. Long-term ground-based
observations {Lockwood and Jerzekiewicz, 2006, Icarus 180, 442; Hammel
and Lockwood 2007, Icarus 186, 291} reveal seasonal brightness changes
whose origins are not well understood. Recent near- IR images of
Neptune obtained using adaptive optics on the Keck Telescope, together
with HST observations {Sromovsky et al. 2003, Icarus 163, 256 and
references therein} which include previous Snapshot programs {GO 8634,
10170, 10534} show a general increase in activity at south temperate
latitudes until 2004, when Neptune returned to a rather Voyager-like
appearance. Further Snapshot observations of these two dynamic planets
will elucidate the nature of long-term changes in their zonal
atmospheric bands and clarify the processes of formation, evolution,
and dissipation of discrete albedo features.

WFPC2 11218

Snapshot Survey for Planetary Nebulae in Globular Clusters of the Local
Group

Planetary nebulae {PNe} in globular clusters {GCs} raise a number of
interesting issues related to stellar and galactic evolution. The
number of PNe known in Milky Way GCs, 4, is surprisingly low if one
assumes that all stars pass through a PN stage. However, it is likely
that the remnants of stars now evolving in Galactic GCs leave the AGB
so slowly that any ejected nebula dissipates long before the star
becomes hot enough to ionize it. Thus there should not be ANY PNe in
Milky Way GCs--but there are four! It has been suggested that these
PNe are the result of mergers of binary stars within GCs, i.e., that
they are descendants of blue stragglers. The frequency of occurrence
of PNe in external galaxies poses more questions, because it shows a
range of almost an order of magnitude. I propose a Snapshot survey
aimed at discovering PNe in the GC systems of Local Group galaxies
more distant than the Magellanic Clouds. These clusters, some of which
may be much younger than their counterparts in the Milky Way, might
contain many more PNe than those of our own galaxy. I will use the
standard technique of emission-line and continuum imaging, which
easily discloses PNe.

WFPC2 11235

HST NICMOS Survey of the Nuclear Regions of Luminous Infrared Galaxies
in the Local Universe

At luminosities above 10^11.4 L_sun, the space density of far-infrared
selected galaxies exceeds that of optically selected galaxies. These
`luminous infrared galaxies' {LIRGs} are primarily interacting or
merging disk galaxies undergoing enhanced star formation and Active
Galactic Nuclei {AGN} activity, possibly triggered as the objects
transform into massive S0 and elliptical merger remnants. We propose
NICMOS NIC2 imaging of the nuclear regions of a complete sample of 88
L_IR 10^11.4 L_sun luminous infrared galaxies in the IRAS Revised
Bright Galaxy Sample {RBGS: i.e., 60 micron flux density 5.24 Jy}.
This sample is ideal not only in its completeness and sample size, but
also in the proximity and brightness of the galaxies. The superb
sensitivity and resolution of NICMOS NIC2 on HST enables a unique
opportunity to study the detailed structure of the nuclear regions,
where dust obscuration may mask star clusters, AGN and additional
nuclei from optical view, with a resolution significantly higher than
possible with Spitzer IRAC. This survey thus provides a crucial
component to our study of the dynamics and evolution of IR galaxies
presently underway with Wide-Field, HST ACS/WFC and Spitzer IRAC
observations of these 88 galaxies. Imaging will be done with the F160W
filter {H-band} to examine as a function of both luminosity and merger
stage {i} the luminosity and distribution of embedded star clusters,
{ii} the presence of optically obscured AGN and nuclei, {iii} the
correlation between the distribution of 1.6 micron emission and the
mid-IR emission as detected by Spitzer IRAC, {iv} the evidence of bars
or bridges that may funnel fuel into the nuclear region, and {v} the
ages of star clusters for which photometry is available via ACS/WFC
observations. The NICMOS data, combined with the HST ACS, Spitzer, and
GALEX observations of this sample, will result in the most
comprehensive study of merging and interacting galaxies to date.

WFPC2/NIC3/ACS/SBC 11144

Building on the Significant NICMOS Investment in GOODS: A Bright,
Wide-Area Search for z=7 Galaxies

One of the most exciting frontiers in observational cosmology has been
to trace the buildup and evolution of galaxies from very early times.
While hierarchical theory teaches us that the star formation rate in
galaxies likely starts out small and builds up gradually, only
recently has it been possible to see evidence for this observationally
through the evolution of the LF from z~6 to z~3. Establishing that
this build up occurs from even earlier times {z~7-8} has been
difficult, however, due to the small size of current high-redshift
z~7-8 samples -- now numbering in the range of ~4-10 sources.
Expanding the size of these samples is absolutely essential, if we are
to push current studies of galaxy buildup back to even earlier times.
Fortunately, we should soon be able to do so, thanks to ~50 arcmin**2
of deep {26.9 AB mag at 5 sigma} NICMOS 1.6 micron data that will be
available over the two ACS GOODS fields as a result of one recent
180-orbit ACS backup program and a smaller program. These data will
nearly triple the deep near-IR imaging currently available and
represent a significant resource for finding and characterizing the
brightest high-redshift sources -- since high-redshift candidates can
be easily identified in these data from their red z-H colors.
Unfortunately, the red z-H colors of these candidates are not
sufficient to determine that these sources are at z=7, and it is
important also to have deep photometry at 1.1 microns. To obtain this
crucial information, we propose to follow up each of these z-H
dropouts with NICMOS at 1.1 microns to determine which are at high
redshift and thus significantly expand our sample of luminous, z=7
galaxies. Since preliminary studies indicate that these candidates
occur in only 30% of the NIC3 fields, our follow-up strategy is ~3
times as efficient as without this pre-selection and 9 times as
efficient as a search in a field with no pre- existing data. In total,
we expect to identify ~8 luminous z-dropouts and possibly ~2 z~10 J-
dropouts as a result of this program, more than tripling the number
currently known. The increased sample sizes are important if we are to
solidify current conclusions about galaxy buildup and the evolution of
the LF from z~8. In addition to the high redshift science, these deep
1.1 micron data would have significant value for many diverse
endeavors, including {1} improving our constraints on the stellar mass
density at z~7-10 and {2} doubling the number of galaxies at z~6 for
which we can estimate dust obscuration.

FLIGHT OPERATIONS SUMMARY:

Significant Spacecraft Anomalies: (The following are preliminary
reports of potential non-nominal performance that will be
investigated.)

HSTARS:

11404 Loss of Lock in level 2 SAA @ 204/1237z.

Following a successful REACQ(1,3,1) at 11:57:01z, there was a loss of
lock @12:37:55z while in SAA2 with QF3STOPF and QSTOP flags set & take
data flag went down. TERM EXP scheduled @12:58:20z. Observation
affected: NICMOS #30, proposal 08795.

11405 REACQ(2,1,2) fine lock backup on FGS 2 only during LOS @
204/1650z.

QF1STOPF and QSTOP flags set on FGS 1. Observation affected: WFPC 75
TO 76, ACS 2, NICMOS 32; proposal 11144

COMPLETED OPS REQUEST: (None)

COMPLETED OPS NOTES: (None)

******************************** SCHEDULED**** SUCCESSFUL
FGS GSacq************************ 7******************* 7
FGS REacq************************ 7******************* 7
OBAD with Maneuver********* *** * 28***************** 28

SIGNIFICANT EVENTS: (None)