HUBBLE SPACE TELESCOPE

   DAILY REPORT #2601

PERIOD COVERED:  0000Z (UTC) 04/12/00 - 0000Z (UTC) 04/13/00

Daily Status Report as of 104/0000Z

1.0 OBSERVATIONS SCHEDULED AND ACCOMPLISHED:

    1.1 Completed WF/PC-2 8230 (Snapshot Survey of Dynamically Close Galaxy 
Pairs from z=0.1 to z=0.5)

        The WF/PC-2 was used to make snapshot survey observations of 
galactic cluster Gal-Clus-1.  This is to obtain snapshot images of a large, 
well-defined, and dynamically selected sample of close galaxy pairs at 
moderate redshift.  The observations were executed as scheduled, and no 
anomalies were noted.

    1.2 Completed Two Sets of STIS/CCD 8549 (POMS Test Proposal: 
Non-Scripted Parallel Proposal Continuation I)

        The Space Telescope Imaging Spectrograph (CCD) was used to make low 
galactic latitude, non-scripted parallel observations as part of a POMS 
test proposal.  As described in 2.1 and HSTAR 7575, the acquisition for the 
final iteration of this proposal failed, affecting three 
observations.  Otherwise, the observations were completed as planned, and 
no further anomalies were reported.

    1.3 Completed STIS/CCD 8439 (Bias Monitor-Part 2 C8)

        The Space Telescope Imaging Spectrograph (CCD) was used to 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.  The proposal completed with no reported problems.

    1.4 Completed Four Sets of WF/PC-2 8457 (UV Earth Flats)

        The WF/PC-2 was used to obtain a series of Ultraviolet Earth 
flats.  The observations were completed with no reported problems.

    1.5 Completed Two Sets of STIS/CCD 8437 (Dark Monitor-Part 2 C8)

        The Space Telescope Imaging Spectrograph (CCD) was used to monitor 
the darks.  The proposal completed nominally.

    1.6 Completed Two Sets of WF/PC-2 8460 (Cycle 8 Supplemental Darks pt2/3)

        The WF/PC-2 was used to obtain three dark frames every day to 
provide data for monitoring and characterizing the evolution of hot 
pixels.  The observations completed with no reported problems.

    1.7 Completed STIS/CCD 8284 (Deep STIS Observations of BALQSO PG 0946+301)

        The Space Telescope Imaging Spectrograph (CCD ) was used to study 
AGN outflows to determine of the ionization equilibrium and abundances 
(IEA) in broad absorption line {BAL} QSOs.  In the last few years it has 
become clear that partial coverage of the continuum source and saturation 
are common in BALs, and these frustrate attempts to determine the IEA from 
available HST data because of limitations imposed by the S/N ratio and 
spectral coverage. We will re-observe the most suitable BAL IEA target: PG 
0946+301.  The observation completed with no reported problems.

    1.8 Completed Five Sets of WF/PC-2 8090 (POMS Test Proposal: WF-II 
Parallel Archive Proposal Continuation)

        The WF/PC-2 was used in the parallel mode to make some low galactic 
latitude archive observations.  The program will be used to take parallel 
images of random areas of the sky.  The observations were executed as 
scheduled, and no anomalies were noted.

    1.9 Completed STIS/CCD/MA1 8424 (MAMA Sensitivity and Focus Monitor C8)

        The Space Telescope Imaging Spectrograph (CCD and MA1) was used to 
make observations of object GRW+70D582 in order to measure the sensitivity 
and to focus monitor C8.  This also is to monitor sensitivity of each MAMA 
grating mode to detect any change due to contamination or other causes, and 
to monitor the STIS focus in a spectroscopic mode.  A wavelength 
calibration was also taken.  The observations were completed as planned, 
and no anomalies were reported.

    1.10 Completed WF/PC-2 8390 (Expansion Parallax Distances to Planetary 
Nebulae)

        The WF/PC-2 was to be used to make observations of the planetary 
nebula NGC7009 in order to study its parallax distance.  As described in 
2.1 and HSTAR 7575, the acquisition for this proposal failed, affecting 
nine observations.

    1.11 Completed STIS/CCD/MA2 7359 (Chemical Abundances in QSO Broad 
Absorption Line Regions)

        The Space Telescope Imaging Spectrograph (CCD and MA2) was used to 
make observations of the quasar QSO-143648 in order to study the chemical 
abundances in the QSO's broad absorption line regions.  These observations 
are designed to test the possible models for high metallicity in BALQSOs 
and, indirectly, test the origins of the BAL phenomenon.  A wavelength 
calibration image was also taken.  The observations were completed as 
planned, and no anomalies were reported.

    1.12 Completed STIS/MA2 8426 (Cycle 8 MAMA Dark Measurements)

        The Space Telescope Imaging Spectrograph (MA2) was used to make a 
routine Cycle-8 MAMA dark noise calibration measurement.  This proposal 
will provide the primary means of checking on the health of the MAMA 
detectors.  This is done through frequent monitoring of the background 
count rate.  The observations were completed as planned, and no problems 
were reported.

    1.13 Completed WF/PC-2 8448 (Cycle 8 INTFLAT Sweeps, VISFLAT 
Mini-Sweep, and Linearity Test)

        WFPC2 was used to monitor the pixel to pixel flatfield response and 
the VISFLAT lamp degradation, as well as detect any possible changes due to 
contamination.  The observations completed nominally.

    1.14 Completed STIS/CCD 8168 (The Optical Counterpart of the Soft 
Gamma-ray Repeater 1900+14)

        The Space Telescope Imaging Spectrograph (CCD) was used to observe 
soft gamma-ray repeater {SGR} 1900+14, one of only four known, which are 
likely an exotic class of neutron star known as magnetars with ultra-strong 
surface magnetic fields.  The proposal completed with no reported problems.

2.0 FLIGHT OPERATIONS SUMMARY:

    2.1 Guide Star Acquisitions:
       Scheduled Acquisitions: 7
Successful: 6

        HSTAR 7575 documents a guide star acquisition failure at 
103/122326Z.  This occurred when the scan step limit was exceeded on 
FGS-2.  The proposals described in 1.2 and 1.10 were affected.
  Scheduled Re-acquisitions: 8
Successful: 8

    2.2 FHST Updates:
Scheduled: 17
Successful: 17

    2.3 Operations Notes:

        Using ROP SR-1A, the SSR EDAC error counter was cleared once.

        There was a STIS EMC retry at 103/1215542Z.  The STIS flight 
software error counter was cleared at 103/1237Z per ROP NS-12.

        A TTR was written for a negative mode 1 acquisition at 
104/011400Z.  Per an operations note steps were taken to successfully 
re-acquire data.

3.0 SIGNIFICANT FORTHCOMING EVENTS:

        Continuation of normal science observations and calibrations.

/CAW