HUBBLE SPACE TELESCOPE - Continuing to collect World Class
Science
DAILY REPORT #4724
PERIOD COVERED: 5am October 24 - 5am October 27, 2008 (DOY
298/0900z-301/0900z)
OBSERVATIONS SCHEDULED
FGS 11901/11212
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.
WFPC2 11867
HH 30
This is a end-of-life WFPC2 imaging program of the disk
and jet of the
young star HH 30. HH 30 will be observed on PC1 in filters
F555W, F675W,
and F814W. Jet emission will be seen in F675W extending to
the NNW.
F555W and F814W each get one orbit of long exposures, and
F675W gets two
orbits to see the jet at large distances. The orientation
is specified
to ensure that the jet is not truncated by the chip edge
and to place
the nearby star XZ Tau in the far corner of WF2.
WFPC2 11796
WFPC2 Cycle 16 Decontaminations and Associated
Observations
This proposal is for the WFPC2 decons. Also included are
instrument
monitors tied to decons: photometric stability check,
focus monitor,
pre- and post-decon internals (bias, intflats, kspots,
& darks), UV
throughput check, VISFLAT sweep, and internal UV flat
check.
WFPC2 11793
WFPC2 Cycle 16 Internal Monitor
This calibration proposal is the Cycle 15 routine internal
monitor for
WFPC2, to be run weekly to monitor the health of the
cameras. A variety
of internal exposures are obtained in order to provide a
monitor of the
integrity of the CCD camera electronics in both bays (both
gain 7 and
gain 15 -- to test stability of gains and bias levels), a
test for
quantum efficiency in the CCDs, and a monitor for possible
buildup of
contaminants on the CCD windows. These also provide raw
data for
generating annual super-bias reference files for the
calibration
pipeline.
WFPC2 11302
WFPC2 CYCLE 16 Standard Darks - Part III
This dark calibration program obtains dark frames every
week in order to
provide data for the ongoing calibration of the CCD dark
current rate,
and to monitor and characterize the evolution of hot
pixels. Over an
extended period these data will also provide a monitor of
radiation
damage to the CCDs.
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
optimally schedule our observations.
FLIGHT OPERATIONS SUMMARY:
Significant Spacecraft Anomalies: (The following are
preliminary reports
of potential non-nominal performance that will be
investigated.)
HSTARS:
11553 - GSAcq (2,0,2) failed to RGA Hold
GSAcq (2,0,2) failed to RGA Hold at 300/09:52:26 due to QSTOP and
QF2STOPF flags on FGS 2.
Observations affected: WFPC Proposal 11867, observations 19 - 20
11554 - REAcq (2,0,2) Loss of Lock while guiding
REAcq (2,0,2), scheduled @300/11:20:28z and 300/12:56:23z were
successful. At 11:28:58z and13:05:43z, stop flag indications (QF2STOPF
and QSTOP) were set on FGS 2. Loss of Lock occurred while guiding under
FGS 2 and P4TAKDAT (Take Data Flag) went down. REAcq (2,0,2) scheduled
@300/14:13:17z
was in RGA Hold (Gyro Control) at AOS. The spacecraft was
in
T2G attitude hold mode. No 486 ESB messages or NSSC-1 STB messages
were received.
Observations affected: WFPC2 Proposal #11867, #21-30.
COMPLETED OPS REQUEST:
18344-0 - Set NSSC-1 ATP for Science SMS Intercept @
299/0717z
COMPLETED OPS NOTES: (None)
SCHEDULED
SUCCESSFUL FAILURE
FGS GSacq
28
27
FGS REacq
06
05
OBAD with Maneuver
68
68
LOSS of
LOCK
3
SIGNIFICANT EVENTS:
Flash Report: WFPC2 Recovery Complete
The WFPC2 recovery via SMS is complete. The WFPC2
mechanisms recovery
was performed. ROP NS-16 was executed to verify the RAM
and PROM dumps.
CCD Auto-erase was initiated, TEC power enabled, and TEC
set-points were
set via the SMS, completing ~299/19:41.
Science activity for WFPC2 resumes at 299/21:46 with a
series of
internal observations such as Bias and Internal Flats. The
first
external image is commanded at 299/22:57.