Daily Report #4724

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 Monte Carlo technique to 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.