HUBBLE SPACE TELESCOPE

   DAILY REPORT #2625

PERIOD COVERED:  0000Z (UTC) 05/16/00 - 0000Z (UTC) 05/17/00

Daily Status Report as of 138/0000Z

1.0 OBSERVATIONS SCHEDULED AND ACCOMPLISHED:

    1.1 Completed Three Sets of WF/PC-2 8460 (Cycle 8 Supplemental Darks pt2/3)

        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 completed with no reported problems.

    1.2 Completed STIS/CCD 8439 (Bias Monitor-Part 2 C8)

        The Space Telescope Imaging Spectrograph (CCD) was used 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 track the evolution of hot 
columns.  The proposal completed with no reported problems.

    1.3 Completed STIS/CCD 8236 (Black Holes and Gas Disks in a Complete 
Sample of Radio-Loud Ellipticals - II: Kinematics)

        The Space Telescope Imaging Spectrograph (CCD) was used to make 
observations of the radio-loud elliptical galaxy UGC-7115.  From these 
observations we will measure the black hole masses, determine the nature, 
kinematics, and structure of the central gas disks and obtain a modeled 
upper limit to their mass accretion rates.  A wavelength calibration image 
was also taken.  The observations were completed as planned, and no 
problems were reported.

    1.4 Completed Three Sets of STIS/CCD 8808 (POMS Test Proposal: STIS 
Non-Scripted Parallel Proposal Continuation III)

        The Space Telescope Imaging Spectrograph (CCD) was used to make 
non-scripted, parallel observations as part of a POMS test proposal.  The 
observations completed with no anomalous activity.

    1.5 Completed STIS/CCD 8437 (Dark Monitor-Part 2 C8)

        The Space Telescope Imaging Spectrograph (CCD) was used to monitor 
the darks.  The proposal completed nominally.

    1.6 Completed WF/PC-2 8609 (Host Galaxy Luminosities of the Most 
Luminous QSOs)

        The WF/PC-2 was used to determine the factors that decide whether a 
galaxy is host to a luminous QSO.  Recent evidence indicates that host 
galaxy spheroid mass is a key factor: we want to test the relationship 
between host galaxy and QSO luminosity at the highest feasible QSO 
luminosities by measuring the luminosities and profiles of host galaxies 
for QSOs with -25.8 > M_V > -27.6.  Current data in this area are 
conflicting.  The observations completed with no reported anomalies.

    1.7 Completed STIS/CCD 8489 (Searching for the Hydrogen Reionization 
Edge of the Universe at 5HST)

        The Space Telescope Imaging Spectrograph (CCD) was used to observe 
36 parallel orbits {4--5 fields of 5--8 orbits each} to constrain the H 
Lyman-edge in emission that marks the transition from a neutral to a fully 
ionized IGM.  This edge is due to recombination from the H Lyman series and 
Lyman continuum, and can be used to constrain zion, one of the most 
important unknown quantities in large scale structure and cosmology.  The 
proposal completed nominally.

    1.8 Completed FGS 8292 (Calibrating the Mass-Luminosity Relation at the 
End of the Main Sequence)

        The Fine Guidance Sensor (FGS1R) was used to make astrometric 
observations of the star GJ469 and other nearby reference stars.  This is 
part of a study to calibrate the mass-luminosity relation for stars less 
massive than 0.2 Msun, with special emphasis on objects near the 
stellar/brown dwarf border.  The observations were completed as planned, 
and no problems were reported.

    1.9 Completed WF/PC-2 8166 (Narrow-Band HAlpha Imaging of the Edge-on 
Galaxy NGC4631)

        The WF/PC-2 was used to make observations of nearby edge-on disk 
galaxies which are essential to determine the role that the disk/halo 
interaction has in galaxy evolution.  Located in a direction of 
exceptionally low Galactic extinction, NGC4631 is particularly suitable for 
a multi-wavelength investigation of extra-planar gas components.  The 
observations completed nominally.

    1.10 Completed STIS/CCD 8549 (POMS Test Proposal: Non-Scripted Parallel 
Proposal Continuation I)

        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.

    1.11 Completed STIS/CCD/MA2 8197 (Detection of ^11B/^10B: Part II)

        The Space Telescope Imaging Spectrograph (CCD and MA2) was used to 
make spectrographic observations of star HD940287 to measure the boron 
isotope ratio (i.e., 11B/10B).  A wavelength calibration image was also 
taken.  The observations were completed as planned, and no anomalies were 
reported.

    1.12 Completed Two Sets of WF/PC-2 8805 (POMS Test Proposal: WFII 
Parallel Archive Proposal Continuation)

        The WF/PC-2 was used to perform a generic target version of the 
WFPC2 Archival Pure Parallel program.  The program will be used to take 
parallel images of random areas of the sky, following the recommendations 
of the Parallels Working.  During the second iteration of this proposal, 
the loss of lock described in 2.1 and HSTAR 7605 occurred.  Otherwise, the 
proposal completed with no further reported problems.

    1.13 Completed WF/PC-2 8459 (Decontaminations and Associated 
Observations Pt. 2/2)

        The WF/PC-2 was used to perform the monthly decons.  Also included 
are instrument monitors tied to decons: photometric stability check, focus 
monitor, pre- and post-decon internals {bias, intflats, kspots, & darks}, 
and UV throughput checks.  The observations were completed nominally.

2.0 FLIGHT OPERATIONS SUMMARY:

    2.1 Guide Star Acquisitions:
       Scheduled Acquisitions:  6
Successful:  6

  Scheduled Re-acquisitions: 10
Successful: 10

    2.2 FHST Updates:
Scheduled: 16
Successful: 16

        Per HSTAR 7605, there was a loss of lock involving FGS-3 at 
137/235720Z, after a successful acquisition.  Lock was recovered by the 
issuance of the new #44 commands.  The proposal described in 1.12 was 
affected, as was WF/PC-2 8460 which occurs during the period of the next 
report.

    2.3 Operations Notes:

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

        The STIS MCE-2 reset at 137/201954Z while the high voltage was off 
and while the vehicle was outside any SAA interval.  The STIS flight 
software error counter was reset at 137/2158Z as directed by ROP 
NS-12.  MAMA-2 was recovered at 137/2347Z via normal SMS commanding at the 
time of the following high voltage on event.

3.0 SIGNIFICANT FORTHCOMING EVENTS:

        Continuation of normal science observations and calibrations.

/CAW