HUBBLE SPACE TELESCOPE

                       DAILY REPORT #2460

PERIOD COVERED:  0000Z (UTC) 09/17/99 - 0000Z (UTC) 09/20/99

Daily Status Report as of 263/0000Z

1.0 OBSERVATIONS SCHEDULED AND ACCOMPLISHED:

   1.1 Completed Four Sets of WF/PC-2 8443 (WF/PC-2 Cycle-8 Supplemental Darks
pt1/3)

       The WF/PC-2 was used to obtain 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 problems were reported.  

   1.2 Completed WF/PC-2 8436 (POMS Test Proposal: WFII Backup Parallel Archive
Proposal II)

       The WF/PC-2 was used to make archive observations parallel to the prime
science observations as part of a POMS test proposal.  This is a POMS test
proposal designed to simulate scientific plans.  The observations were
completed as planned, and no anomalies were reported. 

   1.3 Completed Four Sets of STIS/CCD 8408 (STIS CCD Dark Monitor C8)

       The Space Telescope Imaging Spectrograph (CCD) was used to make a CCD
bias calibration observation.  This is to monitor the darks for the STIS CCD. 
The observations were executed as scheduled, and no anomalies were reported.  

   1.4 Completed WF/PC-2 7371 (The White Dwarf Luminosity Function in NGC 188)

       The WF/PC-2 was used to study the white dwarf luminosity function in the
old open cluster NGC-188.  These data will be one of the first “complete”
samples of white dwarfs {in the sense of containing stars from the full cooling
sequence} all at a known distance, with similar compositions and derived from a
fairly well understood initial mass distribution.  The observations were
executed as scheduled, and no anomalies were noted.  

   1.5 Completed Twelve 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.  

   1.6 Completed Three Sets of STIS/CCD 8409 (STIS CCD Bias Monitor C8)

       The Space Telescope Imaging Spectrograph (CCD) was used to make a CCD
bias calibration observation.  This is to monitor the bias in the 1x1, 1x2,
2x1, and 2x2 bin settings at gain=1, and 1x1 at gain = 4, to build up high-S/N
superbiases and to track the evolution of hot columns.  The observations were
executed as scheduled, and no anomalies were reported.  

   1.7 Completed Two Sets of STIS/CCD 8545 (POMS Test Proposal: STIS
non-scripted parallel proposal continuation VI)

       The Space Telescope Imaging Spectrograph (CCD) was used to make low
galactic latitude, non-scripted parallel observations as part of a POMS test
proposal.  The observations were completed as planned, and no anomalies were
reported.  

   1.8 Completed WF/PC-2 8453 (Cycle 8 Polarization)

       The WF/PC-2 was used to make observations of the standard source star
BD+64D106 in order to verify the stability of the instrument’s polarization
calibration.  The observations were completed as planned, and no problems were
reported.  

   1.9 Completed Two Sets of WF/PC-2 8243 (SINS: The Supernova Intensive Study
- Cycle 8)

       The WF/PC-2 was used to make observations of supernova LMC-SN198. 
Supernovae reveal the last stages of stellar evolution, create the chemical
history of the Universe, energize the interstellar gas, and occupy the center
of attention for the extragalactic distance scale and cosmology.  A wavelength
calibration image was also taken.  The observations were completed as planned,
and no problems were reported.  

   1.10 Completed STIS/MA1 8431 (Doppler Test of Far UV MAMA with Jenkins Slit)

       The Space Telescope Imaging Spectrograph (MA1) was used to execute a
Doppler test to measure the limiting resolving power of the far-ultraviolet
MAMA using the Jenkins 0.100x0.030 slit.  The observations were completed as
planned, and no anomalies were noted.  

    1.11 Completed STIS/CCD/MA1/MA2 8424 (MAMA Sensitivity and Focus Monitor
C8)

       The Space Telescope Imaging Spectrograph (CCD, MA1 and MA2) was used to
make observations of object GRW+70D582 in order to measure the sensitivity and
to focus monitor C8.  This also is to monitor sensitivity of each MAMA grating
mode to detect any change due to contamination or other causes, and to monitor
the STIS focus in a spectroscopic mode.  A wavelength calibration was also
taken.  The observations were completed as planned, and no anomalies were
reported.  

   1.12 Completed Three Sets of WF/PC-2 8194 (Evolution of High-Redshift
Seyfert Galaxies)

       The WF/PC-2 was used to make observations of the high-redshifted Seyfert
galaxies GAL-105216, GAL-105407 and GAL-105325in order to study their
evolutions.  The observations will provide insights into the Seyfert phenomenon
at intermediate redshift and will complement similar HST studies of normal
galaxies, clusters and quasars.  The observations were executed as scheduled,
and no anomalies were noted.  

   1.13 Completed Two Sets of WF/PC-2 6469 (Pyramid Imaging of Circumstellar
Material About Nearby Stars)

       The WF/PC-2 was used to make observations of the curcumstellar material
around the nearby star HD216956.  The WF/PC-2 pyramid was used as a coronagraph
to detect the circumstellar material.  The observations were executed as
scheduled, and no anomalies were noted. 

   1.14 Completed Three Sets of WF/PC-2 8457 (UV Earthflats)

       The WF/PC-2 was used to make a ultraviolet Earth flat calibration
image.  This is to improve the quality of pipeline the ultraviolet flatfields. 
The observations were completed as scheduled, and no problems were reported.  

   1.15 Completed STIS/CCD 8313 (Imaging the Host Galaxies of High Redshift
Type Ia Supernovae)

       The Space Telescope Imaging Spectrograph (CCD) was used to make
observations of 921 and its host galaxy.  The propose is to obtain snapshot,
unfiltered STIS images of distant galaxies of known redshift which have hosted
supernovae {SNe} of Type IA found via the Supernova Cosmology Project.  The
observations were completed as scheduled, and no anomalies were reported.  

   1.16 Completed WF/PC-2 8181 (Resolving Sirius-like Binaries)

       The WF/PC-2 was used to make observations of the star HR3643 in order to
try and resolve these Sirius-like binary star systems.  Subsequent
determinations of the visual orbits of the resolved binaries with the HST will
provide dynamical measurements of the white-dwarf masses.  The observations
were completed as scheduled, and no anomalies were reported.  

   1.17 Completed STIS/CCD 8271 (A Snapshot Survey of LMC Planetary Nebulae: A
Study of Nebular and Late Stellar Evolution)

       The Space Telescope Imaging Spectrograph (CCD) was used to make
medium-resolution slitless spectroscopy snapshot images of the planetary
nebulae LMC-SMP-53 located in the Large Magellanic Cloud to study the parallel
evolution of the nebulae and their central stars.  The observations were
completed as planned, and no problems were reported.  

   1.18 Completed STIS/CCD 7718 (Accretion and Winds in T Tauri Systems)

       The Space Telescope Imaging Spectrograph (CCD) was used to study the
T-Tauri class star HD283654 in order to study the geometry, dynamics and
energetics of accretion and winds in this pre-main-sequence star.  We will also
use the spectra to study the mechanisms responsible for exciting flourescence
of molecular hydrogen.  A wavelength calibration image was also taken.  The
observations were completed as planned, and no anomalies were reported.  

   1.19 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.  

   1.20 Completed STIS/CCD/MA1 7400 (Evidence from Boron for Massive Star
Evolution)

       The Space Telescope Imaging Telescope (CCD and MA1) was used to observe
the B III and B II resonance lines at 2065.8 and 1362.5 Angstroms,
respectively, in a sample of main-sequence and slightly evolved blue star
HD46300 using the HST STIS MAMA detectors and echelle gratings.  A wavelength
calibration image was also taken.  The proposal completed with no reported
problems.

   1.21 Completed WF/PC-2 7285 (Collimation of Astrophysical Jets: The
Proto-Planetary Nebula He 3-1475)

       The WF/PC-2 was used to make observations of proto-planetary nebula
HE3-1475-2 in order to get a collimation of its astrophysical jets.  Recent
observations of this proto-planetary nebula in the N II Lambda 6584 A0 line
with the HST WF/PC-2 have revealed what appear the be large scale flows being
collimated into narrow bipolar jets.  A wavelength calibration image was also
taken.  The observations were completed as scheduled, and no anomalies were
reported. 

   1.22 Completed Two Sets of WF/PC-2 8251 (The Second-Parameter Effect in
Metal- Rich, Globular Clusters: A Snapshot Study of NGC 6441)

       The WF/PC-2 was used to observe the newly- discovered hot horizontal
branch (HB) populations in the metal-rich globular clusters (GCs) NGC 6388 and
NGC 6441 providing an unique opportunity for unraveling the second-parameter
effect.  While it has long been known that at least one parameter besides the
metallicity, Fe/H, determines the HB morphology of GCs, our ignorance as to the
nature of this second parameter {or parameters} has been a major stumbling
block in understanding the formation history and age of the GC system.  The
proposal completed nominally with no reported problems.

   1.23 Completed FGS 8309 (A Link Between Massive Binary Stars and Non-thermal
Radio Emission)

       The Fine Guidance Sensors were used to make astrometric observations of
the massive Wolf-Rayet binary star WR78, WR89 and several nearby reference
stars.  Non-thermal radio emission in Wolf-Rayet stars is explained in terms of
synchrotron emission from shocks in the stellar wind.  The observations were
executed as scheduled, and no anomalies were noted.  

   1.24 Completed STIS/CCD/MA1/MA2 8280 (Origins, Structure and Evolution of
Magnetic Activity in the Cool Half of the H-R Diagram: A STIS Survey)

       The Space Telescope Imaging Spectrograph (CCD, MA1 and MA2) was used to
make observations of star HD31910 to carry out part of a major ultraviolet
spectral survey of "coronal" late-type stars.  A wavelength calibration image
was also taken.  The observations were executed as scheduled, and no anomalies
were noted.  

   1.25 Completed WF/PC-2 7380 (Imagery of IC 349)

       The WF/PC-2 was used to make observations IC349-Apex.  IC349 is the
brightest area in the Pleiades reflection nebulosity, by a factor of about 15. 
Discovered visually by Barnard in 1890, it is a difficult object because it is
only about 30" from 23-Tau, of V=4.2.  The observations were completed as
scheduled, and no problems were reported.  

2.0 FLIGHT OPERATIONS SUMMARY:

   2.1 Guide Star Acquisitions: 

                            Scheduled Acquisitions: 25
                                        Successful: 24
                         Scheduled Re-acquisitions: 17
                                        Successful: 12

       As documented in HSTAR 7261, the acquisition at 263/080827Z and the
acquisitions at 263/090841Z, 263/104522Z, 263/1130223Z, 263/122204Z, and
263/135846Z all failed to RGA control when the search radius limit was exceeded
on FGS-3.  Four proposals, all occurring during the period of the next report,
were affected: STIS/WF/PC-2 6603, WF/PC-2 8457, WF/PC-2 8444, and STIS 8409.

   2.2 FHST Updates: 

                              Scheduled: 62
                             Successful: 62

   2.3 Operations Notes: 

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

       At 262/185822Z and 262/185924Z the battery 2 voltage flagged low with a
value of 27.636 volts (limit 27.64).  At 262/185929 and 262/185936Z the battery
4 voltage flagged low with the same voltage reading (limit 27.64).  Then, at
262/185944Z the main bus A voltage flagged low at 26.649 volts (limit 26.68). 
Each of these occurrences were near the end of an orbit night period.

       An NSSC-1 status buffer dump and reset were performed at 263/0612Z per
ROP NS-3.

3.0 SIGNIFICANT FORTHCOMING EVENTS: 

       Continuation of normal science observations and calibrations.

/DMH