HUBBLE SPACE TELESCOPE - Continuing to collect World Class
Science
DAILY REPORT #4755
PERIOD COVERED: 5am December 11 - 5am December 12, 2008
(DOY
346/1000z-347/1000z)
OBSERVATIONS SCHEDULED
ACS/SBC 11110
Searching for Lyman Apha Emission from FUSE Lyman
Continuum Candidates
We have recently been granted time on FUSE to characterize
the escape
fraction of hydrogen Lyman continuum (Lyc) photons from a
morphologically diverse set of star forming galaxies. The
FUSE program
is designed to provide ~ 5 sigma detections of Lyc photons
emitted from
star forming galaxies with escape fractions ~5%. With this
proposal we
seek hydrogen Lyman alpha (Lya) observations of a
representative subset
of the FUSE program targets to constrain the observational
relationship
between Lyc, Lya, and hydrogen Balmer line emission in
these systems.
Such observations explore the detailed balance between the
simple
optically thin (Case A) and optically thick (Case B)
limits in
recombination theory. The ultimate goal of this program is
to quantify
the relationship between escaping Lya and Lyc emission and
the first
structures that form in the early universe.
FGS 11942
Increasing the Accuracy of HST Astrometry with FGS1R
We propose to observe six exoplanetary system host stars
and two
planetary nebulae central stars with FGS1r. All objects have
been
previously observed under proposals GO-09233, -09969,
-10989, and
-11210. These observations will significantly extend the
time baseline,
permitting improvements in the determination of proper
motion. This
systematic motion must be removed to get at the
perturbation of
interest, either due to exoplanetary companions or the
orbital motion of
the Earth (parallax). In most cases the perturbation
orbits will also
improve. We improve either companion mass or PN parallax.
For one
target, GJ 876, theoretical dynamical modelers have
proposed an
inclination closer to 50 degrees, while FGS3 measurements
indicated an
inclination closer to 84 degrees. These new data, once
combined with our
older FGS3 data, will permit an independent remeasurement
of the
inclination of the outermost companion, and a
re-evaluation of widely
used dynamical algorithms.
FGS 11943
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 for 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.
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 07
07
FGS REacq
00
00
OBAD with Maneuver
14
14
SIGNIFICANT EVENTS:
FLASH Report:
The "final" expected NCS CPL Reservoir
temperature setpoint adjustment
was commanded to +22 degC at 345/23:03:03 UTC.
Some initial signs of the onset of a flood condition were
noted at
345/17:41:00 UTC following the setpoint increase to +20
degC, but the
loop stabilized nicely and has been able to sustain the
additional
2-degree increase since that time. Since the initial
Reservoir setpoint
change at 345/14:22:01 UTC, the Circulator Housing
temperature
(MNCIHSGT) has increased 0.75 K from 279.66 K to 280.41 K.