Daily Rpt #4860

HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science

DAILY REPORT***** #4860

PERIOD COVERED: 5am June 4 - 5am June 5, 2009 (DOY
155/0900z-156/0900z)

OBSERVATIONS SCHEDULED

COS/NUV/S/C 11355

COS NUV Initial On-Orbit Turn-On and Recovery after Anomalous
Shutdown

This proposal is designed for the initial turn-on of the COS NUV MAMA
detector. The same procedure may later be used to recover the detector
after an anomalous shutdown. Anomalous shutdowns can occur as a result
of bright object violations which trigger the Bright Scene Detection
or Software Global Monitor. Anomalous shutdowns can also occur as a
result of MAMA hardware problems. The Initial MAMA turn-on consists of
three tests: a signal processing electronics check; a slow high
voltage ramp-up to an intermediate voltage; and a slow high voltage
ramp-up to the full operating voltage. During each of the two high
voltage ramp-ups, diagnostics are performed during a dark time-tag
exposure. The turn-on is followed by a MAMA Fold Analysis Test. The
complete sequence is contained in visits 1 through 4. If a second
execution is required during cycle 17, visits 5 through 8 will be run
and another proposal prepared for possible future occurrences.

Supports Activities COS-04 and COS-07

COS23/S/C 11356

COS FUV Initial On-Orbit Turn-On

This proposal specifies the procedure for SMOV initial HV turn-on and
ramp-up of the COS FUV detector. (The FUV will have been commanded to
its Operate state to support execution of proposal 11353.) The
procedure is detailed in the Observing Description, but in summary,
the following is done: The initial transition from FUV Operate to
HVLow is broken into two parts, with a gap of 4 hours between turning
on the HV and ramping to the HVLow (SAA) voltage. This will be
followed by 5 cycles of HV ramp-up and return to HVLow. Cycles will
ramp up to successively higher (magnitude) voltage, with the fifth
cycle going to the nominal operating values. There will be a gap of at
least 4 hours between cycles. All HV ramp-up will be done at 10 sec
per HV "step". The step rate and cycle voltage values (for Segments A
and B) must be patched in FSW in each cycle prior to the HV ramp
commanding. Memory monitors will be set on the patched memory
locations. Immediately after any HV commanding, and 4 hours after
ramp-up commanding, the DCE memory will be dumped. Immediately after
HV ramp-up commanding higher than HVLow, short DARK & WAVE exposures
will be obtained. Visits 01 and 02, and all the subsequent even
numbered visits (the ones 4 hours after HV ramp-ups), end with NSSC-1
COS event flag 3 being set. If the flag remains set, subsequent FUV
commanding will be skipped. Thus, Operations Requests must be in place
to clear the flag prior to those subsequent visits. Real-time
monitoring of the telemetry will be used to guide the decisions
whether or not to clear the flag. The final visit (13) provides a
scheduled final opportunity to clear flag 3, and if the flag is
cleared, initiates nominal FUV HV commanding and requests a DARK
exposure.

FGS 11789

An Astrometric Calibration of Population II Distance Indicators

In 2002 HST produced a highly precise parallax for RR Lyrae. That
measurement resulted in an absolute magnitude, M(V)= 0.61+/-0.11, a
useful result, judged by the over ten refereed citations each year
since. It is, however, unsatisfactory to have the direct,
parallax-based, distance scale of Population II variables based on a
single star. We propose, therefore, to obtain the parallaxes of four
additional RR Lyrae stars and two Population II Cepheids, or W Vir
stars. The Population II Cepheids lie with the RR Lyrae stars on a
common K-band Period-Luminosity relation. Using these parallaxes to
inform that relationship, we anticipate a zero-point error of 0.04
magnitude. This result should greatly strengthen confidence in the
Population II distance scale and increase our understanding of RR
Lyrae star and Pop II Cepheid astrophysics.

STIS07/CC 11404

CCD Dark and Bias Monitor for SMOV4/Cycle 17 Activity STIS-07

Monitor the darks for the STIS CCD. Monitor the bias in the 1x1, 1x2,
2x1, and 2x2 bin settings at gain=1, and 1x1 at gain = 4, to build up
high-S/N superbiases and track the evolution of hot columns.

STIS11/CC 11386

STIS-11 External Focus Check

This proposal will check the STIS focus and alignment using two tests.
In the first test, ACQ/PEAK exposures with the G230LB are used to
dither the 0.1x0.09 aperture across a point source to sample the PSF.
Relative counts at different wavelengths give a measure of PSF shape
at different wavelengths. Full frame comparison exposures will also
taken using the 0.1X0.09 and 52X2 apertures, and the relative aperture
throughputs will give an estimate of the image quality at the STIS
aperture plane. In the second test, the target is imaged onto the STIS
CCD using the narrow-band F28x50OII filter. Comparison with previous
OII images will be done to estimate the state of the focus.

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:

18475-0 - Clear COS Event Flag 2 after NUV initial turn on Part 3
completes @ 155/1342z
18467-1 - Clear STIS Event Flag 2 (MAMA1 Checkout Part 3) @ 155/1356z
18489-0 - Disable Sun/Aperture test @ 156/0117z

COMPLETED OPS NOTES: (None)

********************** SCHEDULED***** SUCCESSFUL

FGS GSAcq************** 5****************** 5
FGS REAcq************** 3****************** 3
OBAD with Maneuver **** 5****************** 5

SIGNIFICANT EVENTS:

Flash Report:

The COS NUV fold test was successfully completed at 155/18:43z. The
FUV HV was enabled at 155/21:06z, but not ramped. The FUV detector is
scheduled to be ramped to HVlow at 156/16:55:20z