HUBBLE SPACE TELESCOPE

                       DAILY REPORT #2130

PERIOD COVERED:  0000Z (UTC) 05/22/98 - 0000Z (UTC) 05/26/98

Daily Status Report as of 146/0000Z

1.0 ACTIVITIES SCHEDULED AND ACCOMPLISHED:

   1.1 Completed Eleven Sets of WF/PC-2 7712 (WF/PC-2 Cycle 7 Supplemental
Darks pt2/3)

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

   1.2 Completed Three Sets of STIS/CCD 7803 (Daily Darks to Update
Acquisition Bad Pixel Table Part III)

       The Space Telescope Imaging Spectrograph (CCD) was used to make
daily dark calibration updates.  These daily darks are intended to identify
hot pixels for update to the acquisition on-board FSW hot pixel table.
Daily hot pixel lists can also be used for science data analysis.  The
observations were completed as planned, and no anomalies were reported.

   1.3 Completed Four Sets of STIS/CCD 7926 (CCD Dark and Bias Monitor --
Continued)

       The Space Telescope Imaging Spectrograph (CCD) was used to make
several dark and bias calibration observations.  This is to measure CCD
dark current and bias rates for the two supported amplifier settings {gain
= 1 and gain = 4} in order to gather data for making superdarks and
superbiases.  These observations will also track the growth of hot pixels
on the CCD in general and within the various target acquisition apertures
specifically.  The losses of lock described in 2.1 occurred and the take
data flag went down temporarily during the third iteration of proposal.
Otherwise, the observations were executed as scheduled, and no further
anomalies were noted.

   1.4 Completed NIC/1/2/3 7215 (Line and Continuum Investigation of NGC
1068 and NGC 4151)

       The Near Infrared Camera (Cameras One, Two, and Three) was used to
make observations of the bright, nearby AGN NGC-4151.  This program studies
the high resolution morphology of the continuum and line emission in this
galaxy.  The continuum studies will determine the stellar and non-stellar
luminosity distribution in the galaxy.  The observations were executed as
scheduled, and no anomalies were noted.

   1.5 Completed WF/PC-2 7277 (Calibration of the Cepheid P-L Relation with
Observations of the Maser-Host Galaxy NGC)

       The WF/PC-2 was used to make observations of the maser-host galaxy
NGC-4258 to study its Cepheid variable stars.  These data will help refine
the calibration of the Cepheid period-luminosity relationship.  The
observations were completed as scheduled, and no problems were reported.

   1.6 Completed Eight Sets of NIC/2/3 7907 (NICMOS Pure Parallel Winter 97-98)

       The Near Infrared Camera (Cameras Two and Three) was used to make
pure parallel spectrographic observations of sky regions when another
instrument is prime.  The observations were completed as planned, and no
anomalies were reported.

   1.7 Completed Four Sets of STIS/CCD 7910 (STIS Extragalactic Parallel
Survey)

       The Space Telescope Imaging Spectrograph (CCD) was used to make
extragalactic slitless spectrographic observations as part of the parallel
high galactic latitude survey to search for emission line galaxies.  Data
was taken in parallel, and not subject to proprietary time.  The
observations were executed as scheduled with no anomalies.

   1.8 Completed Two Sets of NIC/1/2 7849 (Metallicity and the Cepheid
Distance Scale)

       The Near Infrared Camera (Cameras One and Two) was used to make
observations of Cepheid variable stars in the M-101 galaxy.  The local
distance scale to galaxies is largely based on the Cepheid
period-luminosity relation.  Motivated by the goal of measuring an accurate
value of the Hubble constant, HST has been used successfully to discover
scores of Cepheid variables in each of about 20 galaxies.  The observations
were executed as scheduled, and no anomalies were noted.

   1.9 Completed Four Sets of WF/PC-2 7909 (POMS Test Proposal: WF II
Parallel Archive Proposal)

       The WF/PC-2 was used to make parallel observations as part of the
POMS test proposal.  This test proposal is designed to simulate scientific
plans.  The observations were completed as planned, and no problems were
reported.

   1.10 Completed FGS 7493 (Calibrating the Mass-Luminosity Relation at the
End of the Main Sequence)

       The FGSs were used to make observations of star GL22-4 in order to
make calibration observations of the mass-luninocity relation at the end of
the main sequence.  The study utilizes HST-FGS and infrared speckle imaging
to calibrate the mass-luminosity relation for stars less massive than 0.2
Msun, with special emphasis on objects near the stellar/brown dwarf border.
The observations were completed as scheduled, and no problems were noted.

   1.11 Completed Four Sets of STIS/CCD 7911 (STIS Galactic Plane Pure
Parallel Program)

       The Space Telescope Imaging Spectrograph (CCD) was used to make low
galactic latitude survey observations in parallel with the prime science
observations.  Short exposures with the 50CCD imaging mode will provide the
wavelength zero-point calibration.  These data will be placed immediately
into the Hubble Data Archive.  The observations were executed as scheduled,
and no anomalies were noted.

   1.12 Completed NIC/1/2 7852 (Weighing the Stellar Halo of NGC 5907 with
NICMOS)

       The Near Infrared Camera (Cameras One and Two) was used to make
observations of the staler halo around NGC-5907 in order to determine its
composition.  This stellar halo has a radial profile that roughly traces
the isothermal profile required to reproduce the rotation curve.  The
observations were executed as scheduled, and no anomalies were noted.

   1.13 Completed Two Sets of 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.

   1.14 Completed WF/PC-2/NIC/1/2/3 7372 (Fundamental Plane,
Morphology-Density Relation, and Lensing in the z=0.83 Cluster)

       The WF/PC-2 and the Near Infrared Camera (Cameras One, Two and
Three) were used to make observations of galactic cluster Gal-Clus-1.
These data will be used to augment the HST mosaics of the clusters with
extensive ground-based spectroscopy and imaging at the Keck, MMT, NTT, and
WHT telescopes.  Near the end of this approximate 10-hour proposal, the
losses of lock described in 2.1 occurred and the take data flag went down
temporarily.  Otherwise, the observations were completed as planned with no
further problems reported.

   1.15 Completed WF/PC-2 6887 (A Photometric Search for Faint Companions
to Nearby Stars)

       The WF/PC-2 was used to make photometric search observations of the
nearby star ROSS248 in order to look for possible companions.  The
technique involves use of the Planetary Camera with wide band pass filters
to photometrically measure for the presence of resolved dark companions.
The observations were executed as scheduled, and no anomalies were noted.

   1.16 Completed NIC/3 7903 (NICMOS GRISM Dispersion Monitoring)

       The near Infrared Camera (Camera Three) was used to perform GRISM
dispersion monitoring by making observations of source HB12.  This is to
monitor the wavelength dispersion solution for the NICMOS grisms after the
NIC/3 Campaign.  The observations were completed as scheduled, and no
anomalies were reported.

   1.17 Completed STIS/CCD7388 (Black Holes and the Centers of Galaxies)

       The Space Telescope Imaging Spectrograph (CCD) was used to continue
our survey of the center of nearby galaxy HR7576.  The major goal is to
survey an unbiased set of galaxies with a potentially wide range of black
hole masses.  The sample has been carefully chosen to optimize leverage on
the character of a proposed correlation of black hole mass with galaxy
mass.   The observations were completed as scheduled with no anomalies.

   1.18 Completed Two Sets of WF/PC-2 5925 (The Polarization and Emission
Line Morphology of Protogalaxy Candidates)

       The WF/PC-2 was used to make observations of the protogalaxy
candidate/radio source 3C256 in order to study its polarization and
emission line morphology.  The extremely blue color of this object may be
caused by star formation, or by scattering of non-stellar continuum light
from the nucleus.  The observations were completed as scheduled, and no
anomalies were noted

   1.19 Completed Three Sets of NIC/2 7330 (The Fueling of Active Nucleii:
A NICMOS Snapshot Survey)

       The Near Infrared Camera (Camera Two) was used to probe the dark
matter distribution of NGC-5643, MARK1211 and NGC-2223 far from their
centers by observing intervening absorption from the MgII doublet (lambda
2800) in the spectrum of one background QSO located in a geometrically
optimal position.  HST observations are required because this feature is in
a wavelength range not accessible from the ground, and the QSO magnitudes
and expected strength of absorption make IUE observations unfeasible.  The
proposal completed as expected with no anomalies.

   1.20 Completed WF/PC-2/STIS/CCD/NIC/1/2/3 7307 (The Formation and
Evolution of Rich Star Clusters in the LMC)

       The WF/PC-2, the Space Telescope Imaging Spectrograph (CCD), and the
Near Infrared Camera (Cameras One, Two and Three) were used to make
observations of the rich star cluster NGC-1868 which is located within the
Large Magellanic Cloud in order to study its formation and evolution.
These observations will help us understand the origin and evolution of rich
star clusters in our own galaxy.  The observations were completed as
scheduled, and no anomalies were reported.

   1.21 Completed Three 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.

   1.22 Completed NIC/3 7901 (NICMOS Post-Campaign Focus
Monitoring)

       The Near Infrared Camera (Camera Three) was used to make some
post-campaign focus monitoring observations by using star cluster NGC-3503.
This proposal is used to determine and monitor the optimal focus and tilt
settings for all three NICMOS cameras after the first NIC/3 observing
campaign.  The observations were executed as scheduled, and no anomalies
were noted.

   1.23 Completed Two Sets of NIC/1/2 7956 (NICMOS Camera 1 Narrow Band
Filter Pointed Super Flats)

       The Near Infrared Camera (Cameras One and Two) was used to obtain
sequences of NICMOS Camera One narrow band filter flat fields. The
observations will be used to build high S/N NICMOS flat fields for the
different filters.  The observations were completed as planned, and no
problems were noted.

   1.24 Completed Two Sets of STIS/CCD 7908 (POMS Test Proposal: STIS
Non-Scripted Parallel Proposal)

       The Space Telescope Imaging Spectrograph (CCD) was used to make
calibration observations as part of the POMS Test Proposal.  This was a
STIS non-scripted parallel proposal.  The observations were completed as
planned, and no problems were reported.

   1.25 Completed STIS/CCD 7645 (STIS FUV-MAMA Cycle 7 Flats)

       The Space Telescope Imaging Spaectrograph (CCD) was used to make
far-ultraviolet flat calibration images.   This program will obtain
FUV-MAMA flat-field observations with the Kr lamp for the construction of
on-orbit D-flats for G140M.  A dark calibration image was also taken.  The
observations were completed as planned, and no anomalies were reported.

   1.26 Completed Two Sets of WF/PC-2 7282 (A Continuing Snapshot Survey
for Compact Stellar Groups and Clusters around Wolf-Rayet Stars)

       The WF/PC-2 was used to make observations of the Wolf-Rayet star
WR13 as part of a continuing snapshot survey of compact stellar groups and
clusters.  The newly imaged clusters allow us to accurately determine the
distances, luminosities, and ages of the WR members.  The observations were
executed as scheduled, and no anomalies were noted.

2.0 FLIGHT OPERATIONS SUMMARY:

   2.1 Guide Star Acquisitions:

                            Scheduled Acquisitions : 27
                                        Successful : 27

       As described in HSTAR 6488, both FGS-2 and FGS-3 lost fine lock
three times beginning at 144/003907Z.  The proposals mentioned in 1.3 and
1.14 were affected.

                          Scheduled Reacquisitions : 26
                                        Successful : 26

   2.2 FHST Updates:

                              Scheduled : 46
                             Successful : 46

   2.3 Operations Notes:

       The SSR EDAC error counter was reset nine times using ROP SR-1.

       The SSR default memory monitors were loaded at 142/1721Z as directed
by an opertions request and ROP SR-7.

       The STIS MCE-2 reset at 143/005427Z while the low voltage was on and
while outside any SAA contour.  HSTAR 6487 was written.  Using ROP NS-12,
the STIS flight software error counter was reset at 143/0140Z.  The MCE-2
was recovered via the SMS at the time of the next MAMA-2 high voltage on at
145/114700Z.

       The ground master image was updated at 144/0507Z.

       As described in HSTAR 6489, the STIS MCE-1 reset at 145/032127Z
while the low voltage was on and while in an SAA contour.  The STIS flight
software error counter was reset at 145/0400Z, using ROP NS-12.  The MCE-1
was recovered at the time of the next MAMA-1 high voltage on as commanded
in the SMS.  Science operations were not affected.

       A NSSC-1 status buffer dump was commanded at 145/1951Z per ROP NS-3.

       The STIS MCE-2 reset at 146/013241Z while the low voltage was on and
while in an SAA contour.  HSTAR 6490 was written.  Per ROP NS-12, the STIS
flight software error counter was reset at 146/0147Z.  The NCE-2 will be
recovered at 147/180035Z via the timeline.  Science was not affected.

3.0 SIGNIFICANT FORTHCOMING EVENTS:

       Continuation of normal science observations and calibrations.

/DMH