HUBBLE SPACE TELESCOPE

                       DAILY REPORT #2375

PERIOD COVERED:  0000Z (UTC) 05/18/99 - 0000Z (UTC) 05/19/99

Daily Status Report as of 139/0000Z

1.0 ACTIVITIES SCHEDULED AND ACCOMPLISHED:

   1.1 Completed 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.

   1.2 Completed Two Sets of WF/PC-2 7621 (WF/PC-2 Cycle 7 Supplemental
Darks PT1/3)

       The WF/PC-2 was used to make supplemental dark calibration images.
This set of calibrations is intended to obtain 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.

   1.3 Completed 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
WR145 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.

   1.4 Completed STIS/CCD/MA1 7511 (Spectroscopy of the Interstellar Medium
in the Magellanic Bridge)

       The Space Telescope Imaging Spectrograph (CCD and MA1) was used to
make spectrographic observations of the interstellar medium (Section
DGIK975) in the Magellanic Bridge.  The proposed observations will provide
an opportunity to investigate the physical conditions within the Bridge
gas, and to determine the chemical composition of important elements such
as C, N, O, Mg, Si, S, and Fe.  A wavelength calibration image was also
taken.  The observations were executed as scheduled, and no anomalies were
noted.

   1.5 Completed Two Sets of WF/PC-2 8441 (WF/PC-2 Decontaminations and
Associated Observations Pt. 1/2)

       The WF/PC-2 was used to make its monthly decontamination operations.
Also included are instrument monitors tied to decons: photometric stability
check, focus monitor, pre- and post-decon internals {bias, internal flats,
k-spots, & darks}, and ultraviolet throughput checks.  All observations
were executed as scheduled, and no anomalies were noted.

   1.6 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.

   1.7 Completed WF/PC-2 6833 (A Cepheid Search in the Virgo Cluster Galaxy
NGC 4571)

       The WF/PC-2 was used to make observations of the Virgo Cluster
galaxy NGC-4571 in order to search for Cepheid variable stars.  The
determination of the distance to the Virgo Cluster is key to establishing
the value of the H_zero.  The observations were completed as planned, and
no problems were reported.

   1.8 Completed Two Sets of STIS/CCD 8470 (POMS Test Proposal: STIS
Non-Scripted Parallel Proposal Continuation V)

       The Space Telescope Imaging Spectrograph (CCD) was used to make high
galactic latitude observations taken in parallel with the prime science
observations as part of a POMS proposal.  This is a STIS non-scripted
parallel Condition VI proposal.  As described in HSTAR 7134 and 2.1, the
acquisition for the second iteration of this proposal defaulted to fine
lock one one FGS only.  Otherwise, the observations were completed as
scheduled, and no further anomalies were reported.

   1.9 Completed WF/PC-2 6461 (High-Resolution Next Bright Galactic Nova)

       The WF/PC-2 was used to make high resolution images of the bright
galactic nova U-Scorpii after it erupted to search for fluorescence and
reflection light echoes from, and small-scale structure in, the nova
circumstellar gas and dust ejecta.  The observations were executed as
scheduled, and no anomalies were noted.

   1.10 Completed Two Sets of STIS/CCD 8406 (POMS Test Proposal: STIS
Non-Scripted Parallel Proposal Continuation V)

        The Space Telescope Imaging Spectrograph (CCD) was used to make
high galactic latitude observations taken in parallel with the prime
science observations as part of a POMS proposal.  This is a STIS
non-scripted parallel Condition V proposal.  The observations were
completed as scheduled, and no anomalies were reported.

   1.11 Completed WF/PC-2 6604 (Photometry of the Oldest Field Population
in the Magellanic Clouds.)

       The WF/PC-2 was used to make both visual and inferred photometric
observations of selected stars in the oldest field in the Large Magellanic
Cloud LMC-063600 (a.k.a., NGC-121)  From these data, the ages and
population densities of the cluster will be measured.  As described in
HSTAR 7134 and 2.1, the acquisition for this proposal defaulted to fine
lock one one FGS only.  Otherwise, the observations were completed as
scheduled, and no further problems were noted.

   1.12 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.  As described in HSTAR 7134 and 2.1, the acquisition for this
proposal defaulted to fine lock one one FGS only.  Otherwise, the
observations were completed as scheduled, and no further problems were
reported.

2.0 FLIGHT OPERATIONS SUMMARY

   2.1 Guide Star Acquisitions:

                            Scheduled Acquisitions : 6
                                        Successful : 6

       As documented in HSTAR 7134, the acquisition at 139/170549Z
defaulted to fine lock back-up on FGS-3 only when FGS-1 exceeded the scan
step limit.  The subsequent re-acquisitons at 138/1839Z, 138/1933Z,
138/2022Z, 138/2109, and 138/2205Z also defaulted to fine lock on one FGS
only.  The proposals described in 1.8, 1.11, and 1.12 may have been
affected.

                          Scheduled Reacquisitions : 10
                                        Successful : 9

       The acquisition at 139/012508Z failed when the scan step limit was
exceeded on FGS-3.  HSTAR 7135 was written.  Two proposals, occurring
during the period of the next report (STIS 8042 and STIS 7949) were
affected.

   2.2 FHST Updates:

                              Scheduled : 17
                             Successful : 17

   2.3 Operations Notes:

       The HST operations team remains in the SAMS back-up facility using
the PRS ground system.  PRS-2 was re-booted at 139/0107Z due to tape drive
problems.

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

       The =97=CD=CDC-1 status buffer was dumped at 138/1258Z per ROP NS-3.

3.0 SIGNIFICANT FORTHCOMING EVENTS:

       Continuation of normal science observations and calibrations.

/DMH