HUBBLE SPACE TELESCOPE

                       DAILY REPORT #2349

PERIOD COVERED:  0000Z (UTC) 04/12/99 - 0000Z (UTC) 04/13/99

Daily Status Report as of 103/0000Z

1.0 ACTIVITIES SCHEDULED AND ACCOMPLISHED:

   1.1 Completed Two Sets of WF/PC-2 7713 (WF/P-2 Cycle 7 Supplemental
Darks pt3/3)

       The WF/PC-2 was used to make supplemental dark calibration images.
This dark calibration program obtains three dark frames every day to
provide data for monitoring and characterizing the evolution of hot pixels.
The observations were completed as planned, and no anomalies were noted.

   1.2 Completed STIS/CCD/MA1/MA2 7653 (LSF Measure of the
MAMA-Spectroscopic Modes)

       The Space Telescope Imaging Spectrograph (CCD, MA1 and MA2) was used
to make observations of HEN1357 to measure the LSF of MAMA spectroscopic
modes with an external target.  A wavelength calibration image was also
taken.  The observations were completed as planned, and no anomalies were
reported.

   1.3 Completed Five Sets of WF/PC-2 7620 (WF/PC-2 Cycle 7 Standard Darks)

       The WF/PC-2 was used to make a series of Cycle 7 standard dark
calibration images.  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.  The observations were executed as scheduled, and no anomalies were
noted.

   1.4 Completed STIS/MA1 7298 (A Snapshot Survey for UV bright Quasars at
redshift below 3)

       The Space Telescope Imaging Spectrograph (MA1) was used to make
ultraviolet snapshot observations of the bright quasar UM627 which has a
redshift (Z) below 3.0.  The goal is to find quasars bright enough in the
ultraviolet for spectroscopic follow-up in the range of 900-1200 Angstroms.
A wave length calibration image was also taken.  The observation were
completed as scheduled, and no anomalies were reported.

   1.5 Completed Two Sets of STIS/CCD 7949 (CCD Dark and Bias Monitor --
Cont. to June 99)

       The Space Telescope Imaging Spectrograph (CCD) was used to conduct a
CCD dark calibration and a bias monitoring program.  It was also scheduled
to track the growth of hot pixels on the CCD in general and within the
various target acquisition apertures specifically.  The observations were
executed as scheduled, and no anomalies were noted.

   1.6 Completed WF/PC-2 6659 (A Search For Superplanets Around Weak T-
Tauri Stars)

       The WF/PC-2 was used to make observations in the 1 micron band of
the T-Tauri class star SU-Aur in order to search for superplanets.  Weak
T-Tauri class stars are thought to have dissipated their circumstellar
disks recently, possibly by forming planetary systems.  The observations
were completed as planned, and no anomalies were reported.

   1.7 Completed Three Sets of STIS/MA2 7950 (Cycle 7 MAMA Dark Measurements)

       The Space Telescope Imaging Spectrograph (MA2) was used to make a
dark calibration image.  This is to establish if the detectors are
performing nominally, that no internal movement of the MCP has taken place,
and establish dark level in orbit for a given operating temperature.  These
darks will be used in later image reduction and also trended over
instrument life time as indicators of detector degradation or damage.  The
observations were completed as planned, and no problems were reported.

   1.8 Completed WF/PC-2 7306 (Halo Microlens Source Systems and their
Underlying Stellar Backgrounds)

       The WF/PC-2 was used to to obtain medium-deep broadband images of
the  source star STAR-0504 for microlensing events, plus one additional
star, to determine a} which star was actually lensed, b} the amount of
crowding in our ground-based frames, c} if the stars are normal in the CMD,
and d} if they lie preferentially at the back of the LMC.  The proposal
completed with no reported problems.

   1.9 Completed WF/PC-2 6354 (Measuring Luminosity Evolution in Z = 0.3
Field Galaxies)

       The WF/PC-2 was used to make snapshot observations of the galactic
cluster Gal-Cluster-1 located at a distance of Z = 0.3.  The targets were
drawn from a much larger pool of galaxies for which the internal kinematics
have been measured from an extensive ground based program.  The
observations were executed as scheduled, and no anomalies were noted.

   1.10 Completed Six Sets of STIS/CCD 8091 (POMS Test Proposal: STIS
Non-Scripted Parallel Proposal Continuation)

       The Space Telescope Imaging Spectrograph (CCD) was used to make high
galactic latitude, non-scripted, parallel observations.  The acquisition
and re-acquisition failures described in 2.1 and HSTAR 7097 occurred during
the third iteration of this proposal, affecting four observations.  The
observations were completed as planned, and no further anomalies were
noted.

   1.11 Completed WF/PC-2 6480 (The Butcher-Oemler Effect: Where Have All
The Spirals Gone?)

       The WF/PC-2 was used to make observations of the blue disk-type
galaxy A851-POS5 in order to study the Butcher-Oemler effect.  Other
observational data show that mergers and tidal interactions were apparently
more common in younger clusters; these may contribute to the disappearance
of spiral galaxies by the present epoch.  The observations were executed as
scheduled, and no anomalies were noted.

   1.12 Completed WF/PC-2 7265 (The Metallicity Distribution of the
Globular Cluster Systems of Giant Elliptical Galaxies)

       The WF/PC-2 was to be used to make integrated broadband photometry
observations of the globular cluster systems in the giant elliptical galaxy
NGC-3842-CE in order to study its metallicity.  These observations will
have a significant impact on our understanding of the origin and nature of
globular cluster systems in galaxies.  The acquisition and re-acquisition
failures described in 2.1 and HSTAR 7097 occurred during this proposal,
affecting four observations.

   1.13 Completed WF/PC-2 8053 (WF/PC-2 Cycle-7 Earth Flats -- Part II)

       The WF/PC-2 was used to take Earth flat calibration images.  This
proposal obtains sequences of Earth streak flats to construct high quality
flat fields for the WF/PC-2 filter set.  The observations were executed as
scheduled, and no anomalies were noted.

   1.14 Completed Two Sets of WF/PC-2 6357 (The Nuclear Morphology of
Elliptical Galaxies)

       The WF/PC-2 was used to make images of the early type, large,
elliptical galaxies NGC-4564 and NGC-4621 (taken from a list of 150
galaxies) in order to study their nuclear morphology.  This survey will
complement Illingworth's snapshot study of later Hubble types.  The
observations were completed as scheduled, and no anomalies were reported.

   1.15 Completed STIS/CCD/MA1 7300 (Hyperfine Induced Transitions as
Probes of Low Density Plasmas)

       The Space Telescope Imaging Spectrograph (CCD and MA1) was used to
make observations of the low density plasma in galaxy NGC-3918.  Hyperfine
induced transitions in ^13C, ^29Si, and N may provide a sensitive density
diagnostic for low density plasmas, as well as a way to measure carbon and
silicon isotope ratios.  A wavelength calibration image was also taken.
The observations were executed as scheduled, and no anomalies were noted.

   1.16 Completed WF/PC-2 8061 (POMS Test Proposal: WF-II Backup Parallel
Archive Proposal)

       This is a POMS test proposal designed to simulate scientific plans.
The proposal was executed as planned, and no anomalies were reported.

   1.17 Completed 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.

2.0 FLIGHT OPERATIONS SUMMARY

   2.1 Guide Star Acquisitions:

                            Scheduled Acquisitions : 8
                                        Successful : 7

       As documented in HSTAR 7097, the acquisition at 102/151501Z failed
when the scan search radius was exceeded.  The following re-acquisition
also failed.  The proposals described in 1.10 and 1.12 were affected.

       Per HSTAR 7098, the acquisition at 103/015015Z defaulted to fine
lock backup on FGS-3 only when the scan step limit was exceeded on FGS-1.
STIS proposal 7949 which occurs during the period of the next report may
have been affected.

                          Scheduled Reacquisitions : 8
                                        Successful : 7

       See first comment above.

   2.2 FHST Updates:

                              Scheduled : 20
                             Successful : 20

   2.3 Operations Notes:

       Using ROP SR-1, the SSR EDAC error counter was cleared three times.

       The Gyro-3 drift rate bias slope for the last 7-day interval is
-6.74 arcsec/hour/day (was +2.01), and the slope for the last 2-day
interval is -12.75 arcsec/hour/day (was +1.32).  While the 7-day slope
meets the +/-10.8 arcsec/hour/day desired limit for Gyro-3 re-installation
into the control loop without nulling, the 2-day slope does not.

       An HSTPS configuration change was performed between 102/1645Z and
102/1720Z.

3.0 SIGNIFICANT FORTHCOMING EVENTS:

       Continuation of normal science observations and calibrations.

/DMH