HUBBLE SPACE TELESCOPE

                       DAILY REPORT #2117

PERIOD COVERED:  0000Z (UTC) 05/05/98 - 0000Z (UTC) 05/06/98

Daily Status Report as of 126/0000Z

1.0 ACTIVITIES SCHEDULED AND ACCOMPLISHED:

   1.1 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.

   1.2 Completed 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 Two 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.

   1.4 Completed 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 observations were executed as scheduled, and no
anomalies were noted.

   1.5 Completed STIS/CCD/MA2 7393 (Black Hole A0620-00 and
Advection-Dominated Accretion)

       The Space Telescope Imaging Spectrograph (CCD and MA2) was used to
make observations of soft X-ray transient V616-Mon.  These data might
provide the most clear-cut evidence presently available for the existence
of black holes.  The observations were executed as scheduled, and no
anomalies were noted.

   1.6 Completed Two Sets of WF/PC-2 7625 (WF/PC-2 Cycle 7 Earth Flats)

       The WF/PC-2 was used to make a series of Earth flat calibration
images.  These flat fields will allow mapping of the OTA illumination
pattern and will be used in conjunction with previous internal and external
flats to generate new pipeline superflats.  The observations were completed
as planned, and no anomalies were reported.

   1.7 Completed Four 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.

   1.8 Completed Three 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.

   1.9 Completed NIC/1/2/3 7854 (The Onset of Axisymmetry in
Proto-Planetary Nebulae)

       The Near Infrared Camera (Cameras One, Two and Three) was used to
make observations of the axissysmitry of the proto-planetary nebula CIT6.
The high-resolution imaging and multicolor polarimetric capabilities of
NICMOS comprise a superb combination for studying the processes by which
evolved (approximately one solar mass) stars shed their outer layers to
form planetary nebulae.  The observations were completed as planned, and no
problems were reported.

   1.10 Completed 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.

   1.11 Completed WF/PC-2 7409 (Resolving sdB Binary Systems)

       The WF/PC-2 was used to make observations to try and resolve the sdB
class binary system Star-13114.  This is a continuation of the approved
Cycle 6 Proposal No. 6351, which due to unlucky circumstances did not
succeed in obtaining any data until 8/30/96.  The observations were
completed as scheduled, and no anomalies were reported.

   1.12 Completed STIS/CCD 7666 (CCD Linearity and Shutter Stability)

       The Space Telescope Imaging Spectrograph (CCD) was used to make some
CCD linearity and shutter stability calibration checks.  CCDs can suffer
from non-linearities at low, high {or both} intensity. Such effects can be
subtle, but important contributor to error budgets for routine science
observations and are sometimes recognized only after limitations are
detected in careful analyses of science data.  The observations were
completed as scheduled, and no anomalies were noted.

   1.13 Completed WF/PC-2 7386 (A Snapshot Survey of Nova Shells)

       The WF/PC-2 was used to make observational images of a super nova
shell in order to detect and measure its expanding gaseous shell.  These
observations will trace the distribution of hot and cool gas in the nova
shells, and show their degree of inhomogeneity on both large and small
scales.  The observations were completed as scheduled, and no problems were
noted.

   1.14 Completed NIC/1/2/3 7829 (Mapping H_2 Emission around T Tauri Stars)

       The Near Infrared Camera (Cameras One, Two, and Three) was to be
used to study the distribution of circumstellar dust and molecular {H_2}
gas around six classical T Tauri stars {cTTS}, probing both the near
circumstellar environment {the accretion disk} as well as the environment
further out where strong winds from these stars may be interacting with
remnants of the cloud material from which they formed.  The primary goal is
to map the distribution of the molecular gas
around cTTS.  As described in HSTAR 6459 and in 2.1, the acquisition and
the two-reacquisitions for this approximate three-and-one-half-hour
proposal failed and the take data flag remained down.

   1.15 Completed 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.

   1.16 Completed NIC/1/2/3 7896 (A NIR Snapshot Survey of Ultraluminous IR
Galaxies)

       The Near Infrared Camera (Cameras One, Two and Three) was used to
make snapshot survey observations of the ultraluminous infrared galaxy
QDOTULIR06.  Nearly all of these galaxies show evidence for a recent tidal
interaction, and we will search for evidence of the merger progenitors near
the center of each galaxy, a task made significantly easier with NIR
imaging.  The observations were completed as planned, and no anomalies were
noted.

   1.17 Completed WF/PC-2 7470 (A Snapshot Survey of Galactic Globular
Clusters)

       The WF/PC-2 was used to make snap shot survey observations of the
crowded center of the galactic globular cluster NGC-6273.  The resulting
color-magnitude diagram will include all stars down to about one magnitude
below the main-sequence turnoff.  The observations were completed as
scheduled, and no problems were reported.

   1.18 Completed STIS/MA1 7604 (Cycle 7 MAMA Dark Measurements)
30|35\;
       The Space Telescope Imaging Spectrograph (MA1) was used to make MAMA
dark measurements.  These darks will be used in later image reductions and
also trended over the instrument's life time as an indicator of the
detector's degradation or damage.  The observations were completed as
scheduled, and no problems were reported.

   1.19 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 clusters which are located within the Large
Magellanic Cloud in order to study their 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.

   1.20 Completed S/C 7954 (FGS-1R Optimization)

       Desorption and gravity release effects have modified the morphology
and modulation of the FGS1R Transfer Function.  This test will accomplish a
re-optimization of the performance of FGS1R by adjusting the FF3 mirror
until the S Curve at the center of the field of view is comparable to the
optimized S Curve obtained during SMOV.  This test requires special data
downlinks and uplinks for real-time commanding of the FF3.  The test
concluded with no reported problems.

2.0 FLIGHT OPERATIONS SUMMARY:

   2.1 Guide Star Acquisitions:

                            Scheduled Acquisitions : 12
                                        Successful : 11
                          Scheduled Reacquisitions : 8
                                        Successful : 6

       The acquisition at 125/1533Z and the re-acquisitions at 125/1639Z
and 125/1709Z failed when the search radius limit was exceeded.  HSTAR 6459
was written.  The proposal described in 1.14 was affected.

   2.2 FHST Updates:

                              Scheduled : 30
                             Successful : 30

   2.3 Operations Notes:

       The SSR EDAC counts were cleared using ROP SR-1.

       As a result of the acquisition failures described above, an ARU/PRT
was performed at 125/1805Z.  The following acquisitions were successful.
Also, using ROP NS-11, the NICMOS error counter was cleared.

       The optimization of FGS-1R, as described in 1.20, continues.  Today,
an Internal Test Source (ITS) acquisition was performed at 125/2330Z.  The
Articulated Mirror Assembly (AMA) was commanded eight steps in the reverse
direction at 125/2354Z, as directed by operations request, with no
anomalous behavior reported.  Another ITS acquisition was executed at
126/0203Z, along with two POS exposures.  Two S-curves were produced.
After an analysis meeting today, another AMA move will be performed.

3.0 SIGNIFICANT FORTHCOMING EVENTS:

       Continuation of normal science observations and calibrations.

/DMH