HUBBLE SPACE TELESCOPE

                       DAILY REPORT #2363

PERIOD COVERED:  0000Z (UTC) 04/30/99 - 0000Z (UTC) 05/03/99

Daily Status Report as of 123/0000Z

1.0 ACTIVITIES SCHEDULED AND ACCOMPLISHED:

   1.1 Completed Eight 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 Six 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.

   1.3 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.

   1.4 Completed WF/PC-2 7341 (Absolute Proper Motions of Nearby Dwarf
Spheroidal Galaxies)

       The WF/PC-2 was used to measure precise absolute proper motions for
four dwarf spheroidal satellites of the Milky Way using
spectroscopically-confirmed background QSOs to define a zero-velocity
reference frame.  The observation completed as planned with no reported
anomalies.

   1.5 Completed WF/PC-2 6356 (SNAPSHOT Survey of Ultraluminous Infrared
Galaxies)

       The WF/PC-2 was used to make observations of galaxy Gal-002734 as
part of a survey of ultraluminous infrared galaxies.  The nature of
ultraluminous infrared galaxies has generated considerable controversy.
The two main issues are: {1} are they powered by violent bursts of star
formation or by hidden quasars?  {2} are interactions and mergers
invariably involved?  The observations were executed as scheduled, and no
anomalies were noted.

   1.6 Completed Six Sets of STIS/CCD 8393 (POMS Test Proposal: STIS
Non-Scripted Parallel Proposal Continuation IV)

       The Space Telescope Imaging Spectrograph (CCD) was used to make
POMS, non-scripted, low galactic latitude observations made in parallel
with the prime science observations.  The observations were executed as
scheduled, and no anomalies were noted.

   1.7 Completed WF/PC-2 7466 (From Globular Clusters to Tidal Dwarfs:
Structure Formation in Tidal Tails.)

       The WF/PC-2 was used to make observations of the globular clusters
(et al.) within the tidal tail of galactic merger NGC-3921.  By modeling
these systems with N-body hydrodynamic codes, can we identify the physical
circumstances and formation histories which can produce tidal dwarfs, star
clusters, and other structures in tidal tails.  The observations were
completed as planned, and no anomalies were reported.

   1.8 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-4503 and NGC-4233  (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.

   1.9 Completed Two Sets of WF/PC-2 6967 (Blue Continuum Snapshots of 3CR
Radio - Continued Galaxies)

       The WF/PC-2 was used to make observations of the radio galaxies
3C446.0 and 3C267.0.  Radio galaxies are an important class of
extragalactic objects: they represent one of the most energetic
astrophysical phenomena and they may be used as probes of their
environments.  They are unique probes of the early Universe.  The
observations were completed as planned, and no problems were reported.

   1.10 Completed STIS/MA1 7272 (Helium Absorption by Protogalactic Gas)

       The Space Telescope Imaging Spectrograph (MA1) was used to make
observations of PKS1935-69.  These observations will provide substantially
improved S/N and substantially reduced geocoronal contamination compared
with extant GHRS spectra, providing a much more secure measure of both
discrete cloud and diffuse IGM contributions to the He-II opacity in this
sightline.  A wavelength calibration image was also taken.  The
observations were completed as planned, and no problems were reported.

   1.11 Completed Nine 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.

   1.12 Completed FGS 7486 (Fixing the Mass of the Bright Giant HD 173764)

       The Fine Guidance Sensors (TRANS Mode) were used to make astrometric
observations of the large, massive, giant, spectroscopic binary star
HD173764 (Class G4 II + B9  ) which has an estimated distance of about 150
PCS.  With its 832 day period, the binary will be observable over a large
range of orbital motion during the next year.  The observations were
executed as scheduled, and no anomalies were noted.

   1.13 Completed WF/PC-2/STIS/CCD 7615 (Determination of the Mass Function
of a Globular Cluster Through Gravitational Microlensing)

       The WF/PC-2 and the Space Telescope Imaging Spectrograph (CCD) were
used to make gravitational microlensing observations of the large globular
cluster NGC-6656 located in Sagittarius in order to study its mass
function.  Gravitational microlensing offers a unique and direct method of
determining the masses of stars and other compact objects down to planetary
masses.  A bias and dark calibration observations were also taken.  The
observations were completed as planned, and no problems were reported.

   1.14 Completed STIS/CCD 7672 (STIS CCD Sensitivity Monitor)

       The Space Telescope Imaging Spectrograph (CCD) was used to make
observations of standard star AGK+81D266 in order to monitor the
sensitivity of each CCD grating mode to detect any change due to
contamination or other causes.  A wavelength calibration image was also
taken.  The observations were completed as scheduled, and no anomalies were
noted.

   1.15 Completed Nine Sets of STIS/CCD 8057 (STIS CCD Performance Monitor
{continued})

       The Space Telescope Imaging Spectrograph (CCD) was used to monitor
to overall CCD performance.  The observations were executed as scheduled,
and no anomalies were noted.

   1.16 Completed FGS 7597 (Long Term Stability of Transfer Scan Mode in
FGS-1R)

       The Fine Guidance Sensors (FGS-1R) was used to make observations of
the standard star UPGREN69 in order to study the long term stability of the
Transfer Scan Mode.  The observations were executed as scheduled, and no
anomalies were noted.

   1.17 Completed FGS 7598 (Long Term Stability of Transfer Scan Mode in
FGS-3)

       The Fine Guidance Sensor (FGS-3) was used to make observations of
standard star UPGREN69 in order to study the long term stability of the
Transfer Scan Mode.  The observations were completed as planned, and no
problems were reported.

   1.18 Completed WF/PC-2 7377 (Dwarf Elliptical Galaxy Snapshot Survey II)

       The WF/PC-2 was used to make observations of the dwarf elliptical
galaxy FCC146 as part of Snapshot Survey II.  This survey will provide
important information on the globular cluster systems of such galaxies and
the properties of their cores and nuclei.  The observations were completed
as planned, and no anomalies were reported.

   1.19 Completed STIS/CCD 8226 (Discerning the Origins of Blue Stragglers:
Masses and Rotation Rates)

       The Space Telescope Imaging Spectrograph (CCD) was used to study the
blue stragglers in globular cluster NGC-5272-BS.  Conventional wisdom holds
that the masses of Blue Straggler Stars in globular clusters are
significantly larger than the turnoff mass.  A wavelength calibration
observation was also taken.  The observations were executed as scheduled,
and no anomalies were noted.

   1.20 Completed Two Sets of WF/PC-2 8152 (Mineralogy and Weathering
History of Mars)

       The WF/PC-2 was used to make high spatial resolution and moderate
spectral resolution 5500 Angstrom to 10,000 Angstrom STIS long-slit imaging
spectroscopy observations of the planet Mars.  This is to identify and
globally map the planet's iron-bearing surface mineralogy.  The
observations were executed as scheduled, and no anomalies were noted.

   1.21 Completed STIS/CCD/MA1/MA2 8280 (Origins, Structure and Evolution
of Magnetic Activity in the Cool Half of the H-R Diagram: A STIS Survey)

       The Space Telescope Imaging Spectrograph (CCD, MA1 and MA2) was used
to make observations of star HD33262 to carry out part of a major
ultraviolet spectral survey of "coronal" late-type stars.  A wavelength
calibration image was also taken.  The observations were executed as
scheduled, and no anomalies were noted.

   1.22 Completed Two Sets of WF/PC-2 7281 (Snapshot Survey of the B2
Sample of Radio Galaxies)

       The WF/PC-2 was used to make snapshot survey observations of the B2
sample radio galaxies B2+1525+29 and B2+1553+24.  This program is aimed to
answer the following key questions: How common are extended nuclear disks?
What is their orientation and morphology?  How common are optical jets?
The observations were executed as scheduled, and no anomalies were noted.

   1.23 Completed FGS 7677 (Monitor the Long Term Stability of FGS-3)

       The goal of these measurements is to monitor the internal positional
stability of FGS3 by measuring the star OF975 and other reference stars in
the M35 check field repeatedly over a one year period.  The results of
these measurements are the stability characteristics of FGS3 which allow an
estimate of differential corrections to OFAD and plate scale.  The
measurements were completed as scheduled, with no reported anomalies.

   1.24 Completed FGS 7678 (Monitor the Long-Term Stability of FGS-1R)

       The goal of these measurements is to monitor the internal positional
stability of the FGSs by measuring the star OF56 in the M35 check field
repeatedly over a one year period. The results of these measurements are
the stability characteristics of the FGS to allow an estimate of
differential corrections to OFAD and Plate Scale.  The observations were
completed as planned, and no problems were reported.

   1.25 Completed Three 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 observations
were completed as planned, and no anomalies were noted.

   1.26 Completed Two Sets of STIS/CCD 8024 (Imaging and Spectra of QSO
Host Galaxies)

       The Space Telescope Imaging Spectrograph (CCD) was used to make
observations of QSO 1701+610 and its host galaxy which is at redshift 0.17.
It will be imaged with the STIS CCD and MAMA to study the morphology of the
host galaxy.  A wavelength calibration image was also taken.  The
observations were completed as planned, and no anomalies were reported.

   1.27 Completed WF/PC-2 7431 (Snapshot Survey of Microlensed Source Stars)

        The WF/PC-2 was used to make snapshot survey images of microlensed
source star MACHO-128.  Gravitational microlensing surveys have revealed an
excess of lensing events over theoretical predictions toward both the Large
Magellanic Cloud and the Galactic Bulge.  The observations were completed
as planned, and no anomalies were reported.

   1.28 Completed WF/PC-2 7504 (Calibration of Nearby Type Ia Supernovae as
Standard Candles: The Next Three-Year Step)

       The WF/PC-2 was used to make observations of parent galaxy NGC-4527
in order to determining its Cepheid distance.  This is to continue the
calibration of the Type 1a supernova as standard candles.  The observations
were completed as planned, and no porblems were reported.

   1.29 Completed STIS/MA2 7284 (Abell 39 --- The Theoretician's Nebula
Confronts The Theoreticians)

        The Space Telescope Imaging Spectrograph (MA2) was used to make
ultraviolet spectrographic observations of the spherical, thin shelled,
planetary nebula Abell 39-OF.  A wavelength calibration image was also
taken.  The observations were completed as scheduled, and no problems were
reported.

2.0 FLIGHT OPERATIONS SUMMARY

   2.1 Guide Star Acquisitions:

                            Scheduled Acquisitions : 28
                                        Successful : 28

                          Scheduled Reacquisitions : 16
                                        Successful : 16

   2.2 FHST Updates:

                              Scheduled : 56
                             Successful : 56

   2.3 Operations Notes:

       The operations team remains in the SAMS backup facility utilizing
the PRS real-time system.

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

       The NICMOS FPA temperature sensor detector #1 was enabled at
120/1107Z.  The NICMOS FPA temperature sensor detector #3 was enabled at
121/0936Z.

3.0 SIGNIFICANT FORTHCOMING EVENTS:

       Continuation of normal science observations and calibrations.

/DMH