HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science

DAILY REPORT       #4715

PERIOD COVERED: 5am October 10 - 5am October 14, 2008 (DOY 284/0900z-288/0900z)

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.

FLIGHT OPERATIONS SUMMARY:

Significant Spacecraft Anomalies: (The following are preliminary reports

of potential non-nominal performance that will be investigated.)

HSTARS:

11529 - GSAcq (2,0,2) Failed to RGA Hold (Gyro Control)

   GSAcq(2,0,2) scheduled at 287/00:48:27 - 287/00:54:44 failed to RGA

   Hold. Acquisition summary revealed FGS-2 achieved fine lock then

           transitioned to SSM control at 287/00:54:03.

   Observation affected: Astrometry only, Proposal #11212.

11530 - GSAcq(2,0,2) failed to RGA Hold (Gyro Control)

   Upon acquisition of signal at 288/05:06:40, the GSAcq(2,0,2)scheduled at

   288/03:52:34 - 03:58:51 had failed to RGA Hold due to (QF2STOPF) stop

   indication flag set on FGS-2.

   Observation affected: Astrometry only, Proposal ID 11212.

COMPLETED OPS REQUEST:

18307-0 - Restore HV Protection for the SSM @ 284/14:25z

COMPLETED OPS NOTES: (None)

                       SCHEDULED      SUCCESSFUL  

FGS GSacq               39                  37                   

FGS REacq               00                  00                     

OBAD with Maneuver 78                  78                        

SIGNIFICANT EVENTS:

FLASH: Restoration of HV Protection

At 284/14:25:46 UTC, the SSM HV Protection capability through the NSSC-1

was successfully restored via Ops Request 18307-0. Executive RTCS 21 was

enabled to send notification of an HV Protect event through the setting

of the former Mechanism Motion flag, and NSSC-1 Global Event Flag 12 was

set to allow this transfer across the PIT to the SSM.