HUBBLE SPACE TELESCOPE

                       DAILY REPORT #2322

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

Daily Status Report as of 064/0000Z

1.0 ACTIVITIES SCHEDULED AND ACCOMPLISHED:

   1.1 Completed Three 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.

   1.2 Completed 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.

   1.3 Completed WF/PC-2 7622 (WF/PC-2 Cycle 7 Internal Monitor)

       The WF/PC-2 was used to make a set of Cycle 7 internal monitoring
calibration measurements.  A variety of internal exposures are obtained in
order to provide a monitor of the integrity of the CCD camera electronics
in both bays {gain 7 and gain 15}, a test for quantum efficiency in the
CCDs, and a monitor for possible buildup of contaminants on the CCD
windows.  A bias calibration and an internal flat calibration image were
also taken.  The observations were executed as scheduled, and no anomalies
were noted.

   1.4 Completed Two 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.

   1.5 Completed STIS/CCD 8080 (STIS Spectroscopic CCD Flatfielding --
Revised)

       The Space Telescope Imaging Spectrograph (CCD) was used to make CCD
flat fielding calibration observations in the spectroscopic mode.  The
observations were completed as planned, and no anomalies were reported.

   1.6 Completed 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 galaxy NGC-3640 (taken from a list of 150 galaxies) in order to
study its 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.

   1.7 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.  Twelve
observations for the third iteration of this proposal may have been
affected by the acquisition default to fine lock backup described in HSTAR
7031 and 2.1.  Otherwise, the observations were completed as planned, and
no further anomalies were noted.

   1.8 Completed Two Sets of STIS/CCD 7948 (CCD Dark and Bias Monitor --
Cont. to Dec. 98)

       The Space Telescope Imaging Spectrograph (CCD) was used 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.  The data will be used 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.

   1.9 Completed WF/PC-2 7278 (The Connection Between The Obscuring Torus
and the Masing Disk in H_20 Me)

       The WF/PC-2 was used to investigate the connection between the
molecular torus and the emission line gas in a complete sample of the
NGC-3079 megamaser (a.k.a., M_20).  The proposal completed nominally with
no reported problems.

   1.10 Completed STIS/CCD 7332 (Improved Hubble Constant from the 0957+561
Gravitational Lens)

       The Space Telescope Imaging Spectrograph (CCD) was used to make
observations of the gravitational lens system 0957+561 in order to improve
the value of the know Hubble Constant.  The image was made to be at least
one magnitude deeper than previous HST data in order to detect more faint
lensed structures.  The observations were executed as scheduled, and no
anomalies were noted.

   1.11 Completed STIS/MA1/CCD 7657 (STIS Spectroscopic and Imaging
Sensitivity, MAMA)

       The Space Telescope Imaging Spectrograph (MA1 and CCD) 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.

   1.12 Completed WF/PC-2 7506 (NGC 1705: A Benchmark for Galaxy Evolution)

       The WF/PC-2 was used to make observations of the irregular  galaxy
NGC-1705 whose stellar content cannot be resolved from ground to obtain
information to be used as a benchmark of galaxy evolution.  For this galaxy
there is direct observational evidence for the presence of a galactic wind,
a phenomenon predicted by most chemical evolution models for this type of
galaxy.  Ten observations for this proposal may have been affected by the
acquisition default to fine lock backup described in HSTAR 7031 and 2.1.
Otherwise, the observations were executed as scheduled, and no further
anomalies were noted.

   1.13 Completed STIS 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.

2.0 FLIGHT OPERATIONS SUMMARY

   2.1 Guide Star Acquisitions:

                            Scheduled Acquisitions : 5
                                        Successful : 5

       As described in HSTAR 7031, the acquisition at 063/214253Z defaulted
to fine lock on FGS-3 only when FGS-1 did not acquire fine lock.  The
proposals described in 1.7 and 1.12 may have been affected.

                          Scheduled Reacquisitions : 11
                                        Successful : 11

   2.2 FHST Updates:

                              Scheduled : 11
                             Successful : 11

   2.3 Operations Notes:

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

       At 063/185547Z there was a STIS EMC re-try which resulted in a STIS
status buffer message.  HSTAR 7030 was written.  The STIS flight software
error counter was reset at 064/2039Z per ROP NS-12.

        A TTR was written for a data hit on the MA downlink service at
064/0308Z when there was an automatic TRDS failover from MA2 to MA1.
Another TTR described a 3-minute, 43-second data drop-out at 064/0400Z due
to a WSGT equipment problem.

       The STIS MCE-2 reset at 064/0646Z while the high voltage was off and
while outside any SAA interval.  Recovery of the MAMA-2 will be via SMS
commanding at 064/1638Z.

3.0 SIGNIFICANT FORTHCOMING EVENTS:

       The Voltage Sensing Circuit (VSC) which inserts the additional
voltage dropping diodes into solar array section 5 and 6 will be disabled
at approximately 064/1306Z.  Since January 25, 1999, the HST has been
unable to use the full solar array complement since an imbalance between
batteries 5 and 6 and batteries 1 through 4 was observed.  This caused the
heat-up of batteries 5 and 6, which has now been attributed to a failure in
the VSC.

       Continuation of normal science observations and calibrations.

/DMH