HUBBLE SPACE TELESCOPE

                       DAILY REPORT #2104

PERIOD COVERED:  0000Z (UTC) 04/16/98 - 0000Z (UTC) 04/17/98

Daily Status Report as of 107/0000Z

1.0 ACTIVITIES SCHEDULED AND ACCOMPLISHED:

   1.1 Completed STIS/CCD/WF/PC-2/NIC/3 7355 (Continuous Ultraviolet
Monitoring of NGC 3516)

       The Space Telescope Imaging Spectrograph (CCD), the WF/PC-2, and the
Near Infrared Camera (NIC/3) were all used to make continuous ultraviolet
observations of galaxy NGC-3516.  Recent intensive IUE monitoring of NGC
4151 and other AGN reveal rapid aperiodic variations down to the shortest
time scales yet probed {~80 min}, strongly correlated throughout the UV and
X-ray with no detectable interband lag.  A wavelength calibration image was
also taken.  As reported in yesterday's report and in HSTARs 6437 and 6438,
two of the re-acquisitions for this proposal failed.  The first, which also
included five losses of lock, affected four STIS observations, one NICMOS
observation, and one WF/PC-2 observation.  Otherwise, the observations were
completed as planned, and other portions of this long proposal succeeded.

   1.2 Completed Three 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.

   1.3 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.

   1.4 Completed NIC/1 7867 (NICMOS Imaging of the Dusty CfA Seyfert Nuclei)

       The Near Infrared Camera (Camera One) was used to make observations
of the Seyfert/Markarian Galaxy MRK471.  These data will allow us to
determine if the Seyfert Type 1/2 dichotomy is best explained by the
unified model, the evolutionary picture, or a combination of both of these
scenarios.  The observations were executed as scheduled, and no anomalies
were reported.

   1.5 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.

   1.6 Completed STIS/CCD 7803 (Daily Darks to Update Acquisition Bad Pixel
Table

       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.

   1.7 Completed NIC/2 7227 (A Search for Low Mass/Sub-Luminous Companions
to M-Stars)

       The Near Infrared Camera (Camera Two) was used to make a search for
low mass/sub-luminous companions to low mass M class stars.  Knowledge of
stellar and sub-stellar masses and luminosities at and below the ~0.08
M{sun} H-burning limit is of fundamental importance.  A dark calibration
image was also taken.  The observations were completed as planned, and no
problems were reported.

   1.8 Completed NIC/1/2/3 7891 (The Initial Mass Function of the Galactic
Bulge)

       The Near Infrared Camera (Cameras One, Two and Three) was used to
make observations of NGC-6558 to measure the complete galactic bulge
luminosity function.  This offers a unique clue to better understanding the
complete stellar content, and hence the stellar mass-to-light ratio, of
spiral bulges and by extension of ellipticals as well.  The observations
were executed as scheduled, and no anomalies were noted.

   1.9 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.

   1.10 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.

   1.11 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.

   1.12 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.

2.0 FLIGHT OPERATIONS SUMMARY:

   2.1 Guide Star Acquisitions:

                            Scheduled Acquisitions : 7
                                        Successful : 7

                          Scheduled Reacquisitions : 7
                                        Successful : 7

   2.2 FHST Updates:

                              Scheduled : 12
                             Successful : 12

   2.3 Operations Notes:

       The SSR correctable EDAC counts were cleared four times, using ROP SR-1.

3.0 SIGNIFICANT FORTHCOMING EVENTS:

       Continuation of normal science observations and calibrations.

/DMH