Документ взят из кэша поисковой машины. Адрес оригинального документа : http://www.stsci.edu/ftp/observing/status_reports/hst_status_03_15_02 Дата изменения: Fri Mar 15 14:57:57 2002 Дата индексирования: Sat Dec 22 19:29:49 2007 Кодировка: Поисковые слова: carina nebula

HUBBLE SPACE TELESCOPE

DAILY REPORT #3073

PERIOD COVERED: 0000Z (UTC) 03/14/02 - 0000Z (UTC) 03/15/02

Daily Status Report as of 074/0000Z

1.0 OBSERVATIONS SCHEDULED AND ACCOMPLISHED:

1.1 Completed Two Sets of STIS/MA1/MA2 8959 (MAMA Dark vs. Temperature)

The Space Telescope Imaging Spectrograph (MA1 and MA2) was used to
measure the dark rate for both MAMA detectors as a function of
instantaneous temperature and recent thermal history. These will be used
to make measurements at the beginning and end of three consecutive SAA-free
orbit blocks. The proposal completed with no reported problems.

1.2 Completed STIS/CCD/MA1/MA2 8961 (End of BEA Test)

The Space Telescope Imaging Spectrograph (CCD, MA1 and MA2) was
used to assess whether STIS sensitivity is significantly below pre-SM3
performance by using two G140L spectra of flux standards. Significantly
degraded sensitivity will trigger additional observations of flux standards
to validate the initial result and/or track subsequent
decontamination. All standards used in this program will have recent
preparatory observations obtained in the same configuration
{8956}. Measurement accuracy will be limited by global sensitivity
fluctuations {less than 5%} rather than photon counting statistics. There
was no reported anomalous activity.

1.3 Completed ACS/WFC 9006 (CCD Temperature Set Point Determination)

The Advanced Camera for Surveys (WFC) was used to adjust the CCD
temperature to nominal operating level. The proposal completed nominally.

1.4 Completed Two Sets of STIS/CCD 8963 (CCD Bias)

The Space Telescope Imaging Spectrograph (CCD) was used to measure
CCD read noise from multiple bias frames obtained in common science modes:
amplifier D, gains 1 and 4 electrons/DN, and binning factors of 1x1, 1x2,
2x1, and 2x2. The read noise measurements before and after NCC turn-on are
then compared, and standard calibration reference files for use in pipeline
reduction of SMOV3B data are constructed. The proposal had no reported
problems.

1.5 Completed Three Sets of FGS/1 9581 (A BEA Science Program: A High
Angular Resolution Survey of Some of the Galaxy's Most Massive Stars)

Fine Guidance Sensor #1 was used to make optimal use of otherwise
unused telescope time while HST's pointing is restricted to the BEA cone
during the first 12 days of SMOV3B. The launch date of Feb 29 placed two
of the Galaxy's most active star forming regions, Trumplers 14 and 16 in
the Carina Nebula, within the BEA for the entire 12 day period. FGS1r was
used to
conduct a high angular resolution survey of the most massive and luminous
stars in these two magnificent clusters to establish the incidence of
binarity at the high mass end of the HR diagram. This survey will close the
detection gap between spectroscopic and speckle surveys in which duplicity
can be concealed and will dramatically improve our knowledge of the IMF at
the high mass end of the main sequence as well as the luminosity function
{LF} of star forming regions which produce such high mass stars. Finally,
this survey will identify targets for an approved SIM Key Science project
to dynamically determine O-star masses. There was no anomalous activity.

1.6 Completed STIS/CCD 8964 (CCD Darks)

The Space Telescope Imaging Spectrograph (CCD) was used to obtain
dark frames twice daily, as in a corresponding calibration
program. Standard calibration reference darks are constructed and hot
pixel lists are updated for use in pipeline reduction of SMOV3B data. All
observations completed without incident.

1.7 Completed STIS/CCD 8958 (Image Quality)

The Space Telescope Imaging Spectrograph (CCD) was used to check
image quality using two tests. In the first test, an ACQ/PEAK was used to
dither the 0.1x0.09 aperture across a point source to sample the
PSF. Light was dispersed entering the spectrograph onto the CCD using the
G230LB grating. Relative counts at different wavelengths will give a
measure of PSF shape at different wavelengths. In the second test, a point
source is imaged onto the CCD through the F28x50OII filter. The resulting
PSF is then compared to the PSF shape prior to SM3B. No problems were noted.

1.8 Completed Five Sets of ASC/HRC 9005 (CCD Functional)

The Advanced Camera for Surveys (HRC) was used to measure the
baseline performance and commandability of the CCD subsystems using
exposures of bias frames, darks and flat fields with tungsten lamp. The
on-board baseline compression algorithm for WFC data are measured. This
procedure is carried out purely with internal targets and observations do
not need to be contiguous. No anomalous activity occurred.

1.9 Completed HST 8968 (Vehicle Disturbance Test)

The Vehicle Disturbance Test {VDT} was used to characterize
uncompensated environmental disturbances acting upon the HST during normal
operation. The VDT is a passive test {not a forced-response test} used to
obtain signatures for both externally induced {e.g. SA-3} and internally
induced {e.g. NCC and ACS mechanisms} disturbances for comparison with past
VDT results. The disturbances observed will be used as the nominal
on-orbit disturbances in pointing control simulations until the next VDT is
run. The test occurs after release, and most of the VDT can be run during
the BEA period. The -V1 sunpoint portion of the VDT occurs after the BEA
period is complete. There were no reported problems.

2.0 FLIGHT OPERATIONS SUMMARY:

2.1 Guide Star Acquisitions:
Scheduled Acquisitions: 6
Successful: 6

Scheduled Re-acquisitions: 0
Successful: 0

2.2 FHST Updates:
Scheduled: 12
Successful: 12

2.3 Operations Notes:

QDV10GT1 (10 Second GG Torque 2) flagged out-of-limits at
073/131620Z. The menmonic was back in bounds at 073/131832Z. HSTAR 8552
was written.

Operations requests were used to initiate:

the ACR setup for neon leak high voltage protection at
073/1340Z
the NSSC-1 high voltage protect table modification at
073/1642Z
the Flight Software 5.8.3 installation at 073/1835Z
this version updates the DT temperature limit and
mitigates the potential SEU-induced spurious command
interrupt
the ASCS/NCS quick update for M8FSW83 at 073/2215Z

The engineering status buffer limit for SESBSLD was updated to '4'
at 073/1626Z, using ROP DF-18A.

The Vehicle Disturbance Test (VDT) #2 (see 1.9 above) executed
nominally between 073/225000Z and 074/065000Z. VDT #2 was a 5-orbit test
at +V3 sunpoint designed to establish HST baseline jitter characteristics
prior to NCS startup. This test will be repeated next week as VDT #4 after
NCS cooldown to observe differences attributable to disturbances from the
NICMOS Cooling System.

Similar to VDT #1, the largest disturbances observed during VDT #2
were reaction wheel zero-speed crossings with amplitudes not exceeding 50
mas. Additional disturbances were observed during mid-day and mid-night
intervals in the HST V2 rotation axis having an amplitude of ~25 mas
lasting 5-minutes or less that were not correlated with HGA motion, RWA
zero-speed crossings, or EOD/EON terminators Spectral post-processing of
the test data will be performed to identify the source of these
events. The control law gains (maneuver gains) used during the VDT amplify
the HST jitter response by a factor of 10 above the nominal control law
(acquisition) gains, so these unidentified disturbances will have an
amplitude of ~2.5 mas when using the nominal post-SM3B control law.

VDT #3 Contingency and the Nominal VDT #3 will begin on Saturday
evening at 11:30 PM local time and Sunday morning at 8:00 AM,
respectively. The purpose of VDT #3 is to capture the NCC startup surging
disturbances shortly after NCS activation.

In support of the VDT #2, there were ten LGBU data takes per the
dictates of ROP PO-5.

The flight operations team returned to the GSFC MOR to support SMOV
activities throughout the upcoming weekend.

3.0 SIGNIFICANT FORTHCOMING EVENTS:

Continuation of Servicing Mission Orbital Verification and the
gradual resumption of normal science observations and calibrations.

/CAW