HUBBLE SPACE TELESCOPE

                       DAILY REPORT #2106

PERIOD COVERED:  0000Z (UTC) 04/20/98 - 0000Z (UTC) 04/21/98

Daily Status Report as of 111/0000Z

1.0 ACTIVITIES SCHEDULED AND ACCOMPLISHED:

   1.1 Completed WF/PC-2 7282 (Collimation of Astrophysical Jets: The
Proto-Planetary Nebula He 3-1475)

       The WF/PC-2 was used to make observations of the Wolf-Rayet star
WR26 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.

   1.2 Completed Three 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.

   1.3 Completed NIC/1 7958 (Polarizers Calibration Augmentation)

       The Near Infrared Camera (Camera One) was used to make observations
of the standard unpolarized point source Cha-DC-F7 to perform a polarizer
calibration augmentation.  Also, the polarization fraction and position
angle of polarization were measured for the standard polarized point source
to determine their absolute accuracy in each polarizer and each camera.
The observations were executed as scheduled, and no anomalies were noted.

   1.4 Completed Three 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.

   1.5 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.

   1.6 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.

   1.7 Completed Five 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.

   1.8 Completed FGS 7492 (The Distances to Dwarf Novae, and the
Calibration of the Technique of Infrared Spectroscopic Parallax)

       The Fine Guidance Sensors was used to make astrometric observations
of the dwarf nova U-Gem and several other reference stars.  The distances
to dwarf novae are poorly known.  The distance to the object can be
measured using a technique of infrared spectroscopic parallax.  The
observations were completed as scheduled, and no anomalies were noted.

   1.9 Completed Three 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.

   1.10 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.

   1.11 Completed STIS/MA2 7647 (STIS NUV-MAMA Cycle 7 Flats)

       The Space Telescope Imaging Spectrograph (MA2) was used to make
near-ultraviolet (NUV) flat calibration images.  This program will obtain
NUV-MAMA flat-field observations with the D2 lamp for the construction of
on-orbit D-flats for G230M.  A dark calibration image was also taken.  The
observations were executed as scheduled, and no anomalies were noted.

   1.12 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.

   1.13 Completed STIS/MA1 7645 (STIS FUV-MAMA Cycle 7 Flats)

       The Space Telescope Imaging Spaectrograph (MA1) 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.

   1.14 Completed NIC/1/2/3 7875 (Searching for Old Stellar Populations in
Candidate Proto-Spheroidals)

       The Near Infrared Camera (Cameras One, Two and Three) was used to
make observations searching for old stellar populations in candidate
proto-spheroid LYN2-1635.  We have compelling evidence from WF/PC-2 images
that these galaxies have optical colors gradients.  The near-infrared is
necessary, however, to reveal color gradients large enough to separate
young and old stellar populations.  Only NICMOS imaging provides enough
spatial resolution and depth to resolve these gradients.  The observations
were completed as planned, and no problems were reported.

   1.15 Completed WF/PC-2/STIS/CCD/NIC/1/2 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 and Two) were used to make observations
of the rich star cluster H11-Cen 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.

   1.16 Completed STIS/MA2 7604 (Cycle 7 MAMA Dark Measurements)

       The Space Telescope Imaging Spectrograph (MA2) 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.

   1.17 Completed Two Sets of WF/PC-2 7590 (Cosmological Parameters Omega
and Lambda From High-Redshift Type IA Supernovae)

       The WF/PC-2 was used to make observations of type 1A supernova
11H0.9Z1 and 11H0.9Z2 in order to study its redshift.  The HST was used to
make direct measurements of the cosmological parameters Omega, Lambda, and
curvature using Type 1A supernovae as a calibrated "standard candle".  The
observations were executed as scheduled, and no anomalies were noted.

   1.18 Completed STIS/CCD 7932 (Spectral Purity and slit throughputs for
the First Order Spectroscopic Modes)

       The Space Telescope Imaging Spectrograph (CCD) was used to make
observations of standard star HD101998 in order to study the spectral
purity and slit throughputs for the first order spectroscopic modes.  The
purpose of this proposal is to measure and quantify this effect by
observing strong absorption lines through slits of different sizes.  A wave
length calibration image was also taken.  The observations were completed
as scheduled, and no problems were reported.

   1.19 Completed Two 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.

   1.20 Completed NIC/2 7897 (Probing Planetary Formation Around
Main-Sequence Stars: A Snapshot Survey)

       The Near Infrared Camera (Camera Two) was used to make snapshort
survey images of the main sequence star HD35187 probing for planetary
formation.  The IR excess main-sequence stars host cool circumstellar dust
disks, which are most likely replenished by the debris of unseen
planetesimals.  The observations were completed as scheduled, and no
problems were noted.

   1.21 Completed WF/PC-2 7501 (Expansion Parallax Distances to Planetary
Nebulae)

       The WF/PC-2 was used to make parallax distance measurements of the
planetary nebula NGC-6572.  The largest impediment to our understanding of
planetary nebulae {PNe} is the lack of reliable distances.  Acquired by
generalized statistical methods in all but a handful of cases, individual
PNe distances are often uncertain by factors of two or more.  The
observations were executed as scheduled, and no anomalies were noted.

   1.22 Completed WF/PC-2 6670 (High-Resolution Imagery of Jets From
Superluminal X-Ray Transients)

       The WF/PC-2 was used to make high-resolution imagery of the jets
from superluminal x-ray transients in object CI-Cam.  Superluminal
transients sources {STSs} are newly discovered galactic sources showing
strong X-ray outbursts associated with sporadic relativistic ejection of
radio emitting plasmoids in a double-jet geometry.  The observations were
completed as planned, and no anomalies were reported.

2.0 FLIGHT OPERATIONS SUMMARY:

   2.1 Guide Star Acquisitions:

                            Scheduled Acquisitions : 10
                                        Successful : 10

                          Scheduled Reacquisitions : 5
                                        Successful : 5

   2.2 FHST Updates:

                              Scheduled : 16
                             Successful : 16

   2.3 Operations Notes:

   Cleared the Solid State Recorder (SSR) EDAC Errors three time (ROP SR-01).

   Cleared NSSC-1 Error Report (ENGREPO) at 110/1245Z (ROP NS-05).

   Dumperd the Status Buffer at 111/0427Z (ROP NS-03).

3.0 SIGNIFICANT FORTHCOMING EVENTS:

   Battery #3 Capacity Test is scheduled to start at 111/1442Z. The first
oppertunity to start the discharge is at 111/1902Z.

/DMH