HUBBLE SPACE TELESCOPE

   DAILY REPORT #2600

PERIOD COVERED:  0000Z (UTC) 04/11/00 - 0000Z (UTC) 04/12/00

Daily Status Report as of 103/0000Z

1.0 OBSERVATIONS SCHEDULED AND ACCOMPLISHED:

    1.1 Completed Two Sets of WF/PC-2 8216 (T Tauri Star Snapshot Survey 
II. Completing the CTTs Sample)

        The WF/PC-2 was used to make observations of the T-Tauri class 
stars known as HO-LUP and GW-LUP as part of Snapshot Survey II.  This 
database will be of fundamental importance to understanding the nature of 
planet-forming environments and their frequency in the galaxy.  The 
observations were executed as scheduled, and no anomalies were noted.

    1.2 Completed Six Sets of 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.

    1.3 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.

    1.4 Completed Five Sets of WF/PC-2 8457 (UV Earth Flats)

        The WF/PC-2 was used to obtain a series of Ultraviolet Earth 
flats.  The observations were completed with no reported problems.

    1.5 Completed Two Sets of 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 Two 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.

    1.7 Completed Two Sets of WF/PC-2 8203 (Dwarf Busting in Abell 868)

        The WF/PC-2 was used to to identify and characterize the 
morphological nature of the dwarf galaxy population{s} responsible for the 
steep upturn seen in Abel 868's luminosity function.  While similar upturns 
have been reported in many clusters, the specifics of the dwarf population 
remain unknown as these objects cannot be resolved from the ground.  What 
type of dwarf galaxies are they ?  Is there more than one population 
contributing ?  How are they clustered ?  These observations are intended 
to answer these questions.  The observations were completed, and no 
problems were reported.

    1.8 Completed STIS/CCD 8796 (POMS Test Proposal: STIS Non-Scripted 
Parallel Proposal Continuation IV)

        The Space Telescope Imaging Spectrograph (CCD) was used in the 
parallel mode to make some low galactic latitude archive observations.  The 
observations were executed as scheduled, and no anomalies were noted.

    1.9 Completed STIS/CCD/MA1 8311 (Moderate Redshift Analogs To 
Lyman-Break Galaxies?)

        The Space Telescope Imaging Spectrograph (CCD and MA1) was used to 
determine whether high luminosity galaxies selected using rest ultraviolet 
luminosity at low-to-moderate redshift {0.2<z<0.7, UV-selected Bright 
Galaxies are related to Lyman-Break galaxies at high redshift {3<z<5} 
selected by the drop-out technique.  The observations completed with no 
reported problems.

    1.10 Completed WF/PC-2 8448 (Cycle 8 INTFLAT Sweeps, VISFLAT 
Mini-Sweep, and Linearity Test)

         The WFPC2 was used to monitor the pixel to pixel flatfield 
response and the VISFLAT lamp degradation, as well as detect any possible 
changes due to contamination.  The observations completed nominally.

    1.11 Completed Two Sets of STIS/MA1 8426 (Cycle 8 MAMA Dark Measurements)

        The Space Telescope Imaging Spectrograph (MA1) was used to make a 
routine Cycle-8 MAMA dark noise calibration measurement.  This proposal 
will provide the primary means of checking on the health of the MAMA 
detectors.  This is done through frequent monitoring of the background 
count rate.  The observations were completed as planned, and no problems 
were reported.

    1.12 Completed WF/PC-2 8230 (Snapshot Survey of Dynamically Close 
Galaxy Pairs from z=0.1 to z=0.5)

        The WF/PC-2 was used to make snapshot survey observations of 
galactic cluster Gal-Clus-1.  This is to obtain snapshot images of a large, 
well-defined, and dynamically selected sample of close galaxy pairs at 
moderate redshift.  The observations were executed as scheduled, and no 
anomalies were noted.

    1.13 Completed STIS/CCD/MA1/MA2 8481 (UV Absorption in an X-Ray 
Selected Sample of Seyfert 1 Galaxies)

       The Space Telescope Imaging Spectrograph (CCD, MA1 and MA2) was used 
to obtain high spatial resolution UV spectroscopy of the sub-arcsecond 
structure in the nuclear regions of a sample of X-ray selected Seyfert 1 
galaxies.  Modelling of ASCA X-ray spectra indicates that this sample may 
possess an intrinsic warm absorber.  The existence of this absorber appears 
to be correlated with intrinsic absorption in the ultraviolet; indications 
are that the two are physically linked.   The proposal completed with no 
reported problems.

    1.14 Completed 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.

    1.15 Completed Four Sets of STIS/CCD 8414 (STIS Sparse Field CTE test 
{Cycle 8))

        The Space Telescope Imaging Spectrograph (CCD) was used to conduct 
CTE measurements using the "sparse field test", along both the serial and 
parallel axes.  This program needs special commanding to provide {a} 
off-center MSM positionings of some slits, and {b} the ability to read out 
with any amplifier {A, B, C, or D}.  All exposures are internals.  The 
observations were completed as planned, and no anomalies were reported.

    1.16 Completed STIS/CCD 8170 (Kinematics of the Young Star Clusters and 
the Gas in the Antennae Galaxies)

        The Space Telescope Imaging Spectrograph (CCD) was used to follow 
up on the previous discovery of over 1000 young star clusters in "The 
Antennae'' {NGC 4038} by obtaining long-slit and slitless spectra of a 
representative sample of clusters with STIS.  These young clusters have the 
luminosities, colors, and radii expected of young globular clusters and 
must have formed during the ongoing merger.  Because of their proximity and 
early stage of merging, the disks of NGC 4038 form an ideal laboratory to 
study cluster formation in progress.  The observations completed nominally.

    1.17 Completed WF/PC-2 8338 (The Evolution of the Host Galaxies of 
Powerful Radio Sources)

        The WF/PC-2 was used to make observations of the host galaxy of the 
powerful radio source known as MRC2014-24.  A combined data set of radio 
galaxies and quasars will allow powerful tests of the relationship between 
radio galaxies and quasars and the evolution of the host galaxies of 
powerful radio sources over a wide range of look-back times.  The 
observations were executed as scheduled, and no anomalies were noted.

2.0 FLIGHT OPERATIONS SUMMARY:

    2.1 Guide Star Acquisitions:
       Scheduled Acquisitions: 8
Successful: 8

  Scheduled Re-acquisitions: 7
Successful: 7

    2.2 FHST Updates:
Scheduled: 21
Successful: 19

        Per HSTAR 7574, the full maneuver updates scheduled for 102/151226Z 
and 102/151511Z failed due to FHST-1.  The subsequent guide star 
acquisition, at 102/155356Z, was successful with minimal errors.

    2.3 Operations Notes:

        The SSR EDAC error counter was cleared twice, per ROP SR-1A.

        A CCS 3.2 NCC Test for the GCMR capability was successfully 
conducted, using TDRS 275, at 102/1427Z, at 102/1612Z, and at 102/1756Z

        There was a STIS EMC retry at 102/144151Z.  The STIS flight 
software error counter was reset at 102/1457Z as directed by ROP NS-12.

3.0 SIGNIFICANT FORTHCOMING EVENTS:

        Continuation of normal science observations and calibrations.

/CAW