HUBBLE SPACE TELESCOPE

                       DAILY REPORT #2338

PERIOD COVERED:  0000Z (UTC) 03/26/99 - 0000Z (UTC) 03/29/99

Daily Status Report as of 088/0000Z

1.0 ACTIVITIES SCHEDULED AND ACCOMPLISHED:

   1.1 Completed Eleven 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.

   1.2 Completed WF/PC-2 7619 (WF/PC-2 Cycle 7 Decontamination)

       The WF/PC-2 was used to conduct a Cycle 7 decontamination procedure.
Ultraviolet-blocking contaminants were removed, and hot pixels cured, by
warming the CCDs to +20C for 6 hours.  A variety of internal images were
taken before and after the decontamination in order to verify its success
and to monitor the instrument health.  The procedures were conducted as
scheduled, and no problems were reported.

   1.3 Completed STIS/CCD/MA2 7657 (STIS Spectroscopic and Imaging
Sensitivity, MAMA)

       The Space Telescope Imaging Spectrograph (CCD and MA2) was used to
make observations of GD71 in order to study the spectroscopic and imaging
sensitivity.  Sensitivity measurements are done for all primary tilts of
the gratings and the prism used with the MAMAs, except for the G140L and
G230L gratings.  Imaging sensitivity measurements are done with all
apertures, including a neutral density filter.  A wavelength and a dark
calibration image were also taken.  The observations were executed as
scheduled, and no anomalies were noted.

   1.4 Completed WF/PC-2 7623 (WF/PC-2 Cycle 7 Internal Flats)

       The WF/PC-2 was used to make a set of internal Cycle 7 calibration
flats which are designed to monitor the pixel to pixel flat field response
and the visflat lamp degradation, as well as detect any possible changes
due to contamination.  The calibration observations were completed as
planned, and no problems were reported.

   1.5 Completed Five 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.

   1.6 Completed STIS/CCD/MA1 7295 (Galaxy Rotation Curves at Large Radius
using Lyman-alpha Absorption Lines)

       The Space Telescope Imaging Spectrograph (CCD and MA1) was used to
make rotational spectrographic observations of the galaxy PG1259+593.  This
is to investigate the outer rotation curves of eight spiral galaxies at
very large galactocentric radii by using the kinematical information from
Lyman-alpha absorption lines in the spectra of background quasars.  A
wavelength calibration image was also taken.  The observations were
executed as scheduled, and no problems were reported.

   1.7 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.

   1.8 Completed STIS/MA1/MA2 7436 (A Complete Sample of Hot Post-AGB Stars
in Globular Clusters)

       The Space Telescope Imaging Spectrograph (CCD/MA1/MA2) was used to
make observations of the globular cluster NGC-6723.  Recent observations
with the Ultraviolet Imaging Telescope have provided a complete sample of
the hot post asymptotic giant branch {post-AGB} population in fourteen
globular clusters.  A wavelength calibration image was also taken.  The
observations were completed as planned, and no anomalies were reported.

   1.9 Completed STIS/CCD 8018 (Demographics of Nuclear Black Holes)

       The Space Telescope Imaging Spectrograph (CCD) was used to make
observations to study the nuclear region of the normal galaxy NGC-4621 in
order to study the demographics of black holes.  Detection of supermassive
black holes in normal galaxies is one of the grand challenges that HST was
designed to meet.  A wavelength calibration observation was also taken.
The observations were executed as scheduled, and no anomalies were noted.

   1.10 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.

   1.11 Completed Two Sets of 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.

   1.12 Completed WF/PC-2 7618 (WF/PC-2 Cycle 7 Photometric Monitor UV/OPT
STD)

       The WF/PC-2 was used to make observations of the standard star
GRW+70D582 as part of a Cycle 7 photometric monitoring program.  This
ultraviolet spectrophotometric standard star was observed in a variety of
filters and cameras to monitor the photometric stability and quantum
efficiency of WF/PC-2 from the far-ultraviolet to near-infrared.  The
observations were completed as scheduled, and no problems were reported.

   1.13 Completed WF/PC-2 6813 (The Oldest Star Clusters of Local Group
Irregular Galaxies)

       The WF/PC-2 was used to make observations of the oldest star cluster
NGC-6822-ST which is located in a irregular galaxy of the Local Group
Galactic Cluster.  Globular clusters of spiral and elliptical galaxies are
well- studied and they have provided much information on the early
histories of these types of galaxies. For irregular galaxies, however, very
little is known about the globular clusters and other old clusters.  The
observations were executed as scheduled, and no anomalies were noted.

   1.14 Completed STIS/CCD 7912 (STIS Parallel Archive Proposal - Nearby
Galaxies - Imaging and Spectroscopy)

       The Space Telescope Imaging Spectrograph (CCD) was used to make
parallel observations of nearby galaxies.  This survey will be useful to
study the star formation histories, chemical evolution, and distances to
these galaxies.  These data will be placed immediately into the Hubble Data
Archive.  The observations were completed as scheduled, and no problems
were reported.

   1.15 Completed FOC/96 7923 (FOC F/96 Turnon)

       The Faint Object Camera (f/96) was used to take an internal flat and
a dark to ensure that the 30-day limit for the FOC is not exceeded.  The
observations were executed as scheduled, and no anomalies were noted.

   1.16 Completed Two 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, high galactic latitude observations made in parallel
with the prime science observations.  The observations were executed as
scheduled, and no anomalies were noted.

   1.17 Completed STIS/CCD/MA2 7759 (Heavy Element Abundances in AV 304, a
B0.5 Main Sequence Star in the Small Magellanic  Cloud)

       The Space Telescope Imaging Spectrograph (CCD and MA2) was used to
make observations of the heavy element abundances in AV 304, a B0.5 main
sequence star in the Small Magellanic Cloud (SMC).  Abundances and
abundance ratios of both heavy and light elements will be compared with
results from H-II regions, supernova remnants, and evolved massive stars in
the SMC and theoretical calculations of nucleosynthesis.  A wave length
calibration image was also taken.  The observations were executed as
scheduled, and no anomalies were noted.

   1.18 Completed WF/PC-2 8059 (POMS Test Proposal: WF-2 Targeted Parallel
Archive Proposal)

       The WF/PC-2 was used to make observations in parallel with the prime
science observations.  The parallel opportunities available with WF/PC-2 in
the neighborhood of bright galaxies are treated in a slightly different way
from the normal pure parallels.  Local group galaxies offer the opportunity
for a closer look at young stellar populations.  The observations were
completed as planned, and no anomalies were reported.

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

       The WF/PC-2 was used to make observations of the radio galaxy
3C424.0.  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.

   1.20 Completed WF/PC-2 6462 (Is IRAS FSC15307+3252 Gravitationally
Lensed ?)

       The WF/PC-2 was used to make observations of IRAS FSC15307+3252 in
order to find out if it is gravitationally lensed.  At a redshift of
z=0.93, IRAS FSC15307+3252 is the most luminous object discovered in the
IRAS all sky survey.  The observations were completed as planned, and no
anomalies were reported.

   1.21 Completed WF/PC-2 7383 (High Resolution Imaging of
Magnetically-Propelled Ejecta from the Cataclysmic Variable AE-Aqr)

       The WF/PC-2 was used to make high resolution observations of the
magnetically propelled ejecta from the cataclysmic variable star AE-Aug.
The recent suggestion is that accreting material in the cataclysmic
variable star is diamagnetic and non-homogeneous.  The observations were
completed as scheduled, and no anomalies were noted.

   1.22 Completed STIS/CCD/MA2 7347 (Direct Imaging of Betelgeuse)

       The Space Telescope Imaging Spectrograph (MA2) was used to make
observations of the super giant star Betelgeuse (a.k.a., BD+75D325 or Alpha
Orionis).  Our UV images of Alpha Orionis obtained with the FOC in 1995
{Cycle 5} are the first direct images of the surface of a star other than
the Sun.  The observations were completed as planned, and no anomalies were
reported.

   1.23 Completed Nine Sets of 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.

   1.24 Completed WF/PC-2 7628 (WF/PC-2 Cycle 7 Photometric Characterization)

       The WF/PC-2 was used to make observations of globular cluster
NGC-2419 as part of a photometric characterization calibration observation.
This is to determine whether any changes in the zeropoint, the spatial
dependence of the zeropoint, or contamination rates have occurred.  One
observation near the end of this approximate two-hour-fifteen-minute
proposal was affected by the loss of lock described in 2.1 and HSTAR 7074.
Otherwise, the observations were executed as scheduled, and no further
anomalies were reported.

   1.25 Completed WF/PC-2 6582 (Are the Damped Lyman-Alpha Systems at z>3
Really Spiral Galaxies?)

       The WF/PC-2 was used to make observations of the damped Lyman-Alpha
systems of object PC0953+474.  We still do not know well the sizes of the
damped Lyman-Alpha systems or their star formation rates.  The observations
were completed as planned, and no problems were reported.

   1.26 Completed WF/PC-2 6430 (Nuclear Structure & Merger-Starburst
Relation in the Ultraluminous IRAS Galaxy NGC-6240)

       The WF/PC-2 was used to make observations the ultraluminous IRAS
galaxy NGC-6240 in order to study its nuclear structure & merger-starburst
relation.  Loops, tidal tails and a double nucleus {separation
approximately 1.5 arcsec = 0.7 kpc} suggest an ongoing merger.  The
observations were executed as scheduled, and no anomalies were noted.

2.0 FLIGHT OPERATIONS SUMMARY

   2.1 Guide Star Acquisitions:

                            Scheduled Acquisitions : 18
                                        Successful : 18
                          Scheduled Reacquisitions : 25
                                        Successful : 25

       Per HSTAR 7074, there was a loss of lock that occurred at
087/004324Z.  The first attempt to reacquire was successful at 087/4545Z,
and the take data flag came back up. The proposal described in 1.24 was
affected.

   2.2 FHST Updates:

                              Scheduled : 43
                             Successful : 41

       The full maneuver updates at 087/113207Z and at 087/113452Z failed
due to tracker 1.  The following acquisition, at 087/1220Z, was successful.
HSTAR 7076 describes these events.

   2.3 Operations Notes:

       Using ROP SR-1, the SSR EDAC ereror counter was cleared six times.

       As directed by ROP RD-7, ESTR-2 was reconditioned at 088/0334Z and
ESTR-3 was reconditioned at 088/0828Z.

3.0 SIGNIFICANT FORTHCOMING EVENTS:

       Continuation of normal science observations and calibrations.

/DMH