HUBBLE SPACE TELESCOPE - Continuing to collect World Class
Science
DAILY REPORT #4690
PERIOD COVERED: 5am September 5 - 5am September 8, 2008
(DOY 249/0900z-252/0900z)
OBSERVATIONS SCHEDULED
NIC2 11826
NICMOS Pre-/post-SM4 Photometry Test
This proposal contains the necessary exposures to
re-calibrate NICMOS.
We will observe all filters that are not part of the standard
monitoring
program with a standard 4-point (NIC1 & NIC2) and
7-point (NIC3) dither
pattern.
NIC1/NIC2/NIC3 11820
NICMOS Post-SAA Calibration - CR Persistence Part 7
Internals for CR persistence
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 11500
ERO: WFPC2 Image of Eta Car
This is a WFPC2 program to be executed before SM4 but used
in
coordination with EROs. It will be among the last images
to be taken
with WFPC2.
FGS 11298
Calibrating Cosmological Chronometers: White Dwarf Masses
We propose to use HST/FGS1R to determine White Dwarf {WD}
masses. The
unmatched resolving power of HST/FGS1R will be utilized to
follow up
four selected WD binary pairs. This high precision
obtained with
HST/FGS1R simply cannot be equaled by any ground based
technique. This
proposed effort complements that done by CoI Nelan in
which a sample of
WDs is being observed with HST/FGS1R. This proposal will
dramatically
increase the number of WDs for which dynamical mass
measurements are
possible, enabling a better calibration of the WD
mass-radius relation,
cooling curves, initial to final mass relations, and
ultimately giving
important clues to the star formation history of our
Galaxy and the age
of its disk as well as in other galaxies. {This project is
part of
Subasavage's PhD thesis work at Georgia State
University.}
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.
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 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.
WFPC2 11203
A Search for Circumstellar Disks and Planetary-Mass
Companions around
Brown Dwarfs in Taurus
During a 1-orbit program in Cycle 14, we used WFPC2 to
obtain the first
direct image of a circumstellar disk around a brown dwarf.
These data
have provided fundamental new constraints on the formation
process of
brown dwarfs and the properties of their disks. To search
for additional
direct detections of disks around brown dwarfs and to
search for
planetary-mass companions to these objects, we propose a
WFPC2 survey of
32 brown dwarfs in the Taurus star-forming region.
WFPC2 11178
Probing Solar System History with Orbits, Masses, and
Colors of
Transneptunian Binaries
The recent discovery of numerous transneptunian binaries
{TNBs} opens a
window into dynamical conditions in the protoplanetary
disk where they
formed as well as the history of subsequent events which
sculpted the
outer Solar System and emplaced them onto their present
day heliocentric
orbits. To date, at least 47 TNBs have been discovered,
but only about a
dozen have had their mutual orbits and separate colors
determined,
frustrating their use to investigate numerous important
scientific
questions. The current shortage of data especially
cripples scientific
investigations requiring statistical comparisons among the
ensemble
characteristics. We propose to obtain sufficient
astrometry and
photometry of 23 TNBs to compute their mutual orbits and
system masses
and to determine separate primary and secondary colors,
roughly tripling
the sample for which this information is known, as well as
extending it
to include systems of two near-equal size bodies. To make
the most
efficient possible use of HST, we will use a Monte Carlo technique to
optimally schedule our observations.
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.
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.
FLIGHT OPERATIONS SUMMARY:
Significant Spacecraft Anomalies: (The following are
preliminary reports
of potential non-nominal performance that will be
investigated.)
HSTARS:
11473 - GSAcq(1,2,1) not attempted
The GSacq(1,2,1) scheduled at 251/00:16:15 was not attempted.
Observations affected: NIC Proposal 175 and 176
11475 - REAcq(1,2,1) not attempted
REacq(1,2,1) scheduled at 251/01:53:31 was not attempted.
Observations affected: NIC Proposal 177, 178 and 179
11476 - REAcq(1,2,1) fails while LOS
REACQ(1,2,1) at 13:51:48 appears to have failed but
engineering recorder data is needed for determination of actual events.
TERM EXP command was at 14:47:16 (before AOS time), therefore vehicle
was not expected to be in fine lock at AOS.
Further information and data extracts after engineering recorder dump
currently scheduled for day 251/22:41.
Observations affected: WFPC 46, proposal 11178.
COMPLETED OPS REQUEST: (None)
COMPLETED OPS NOTES: (None)
SCHEDULED
SUCCESSFUL
FGS GSacq 26
25
FGS REacq
14
12
OBAD with Maneuver
80
78
SIGNIFICANT EVENTS: (None)