HUBBLE SPACE TELESCOPE

   DAILY REPORT #2805

PERIOD COVERED:  0000Z (UTC) 02/08/01 - 0000Z (UTC) 02/09/01

Daily Status Report as of 040/0000Z

1.0 OBSERVATIONS SCHEDULED AND ACCOMPLISHED:

    1.1 Completed Two Sets of STIS/CCD 8837 (CCD Dark Monitor-Part 1)

        The Space Telescope Imaging Spectrograph (CCD) was used to monitor 
the darks.  The proposal completed with no reported problems.

    1.2 Completed Four Sets of WF/PC-2 8827 (Cycle 9 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 proposal completed nominally.

    1.3 Completed STIS/CCD/MA2 8673 (The Properties of Ly-Alpha Absorbers 
at Redshifts Between 0.9HST)

        The Space Telescope Imaging Spectrograph (CCD and MA2) was used 
obtain new Echelle resolution spectra of three bright quasars which, when 
combined with archived and scheduled observations, will be used to 
characterize the properties of Ly-Alpha absorbers in the redshift range 
0.9<z<1.6.  There were no reported problems.

    1.4 Completed Three 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 Group.  The proposal completed with no reported 
problems.

    1.5 Completed STIS/CCD/MA1 8662 (A Snapshot Survey of the Hot 
Interstellar Medium)

        The Space Telescope Imaging Spectrograph (CCD And MA1) was used to 
obtain snapshot STIS echelle observations of key tracers of hot 
interstellar gas {C IV, N IV, and Si IV} for selected FUSE Team O VI survey 
targets with known UV fluxes.  By taking advantage of the snapshot 
observing mode we will efficiently obtain a large number of spectra 
suitable for the study of the highly ionized hot component of the 
interstellar medium {ISM}.  Our goals are to explore the physical 
conditions in and distribution of such gas, as well as to explore the 
nature of the interfaces between the hot ISM and the other interstellar gas 
phases.  The observations completed with no reported problems.

    1.6 Completed WF/PC-2 8597 (The Fueling of Active Nuclei: Why are 
Active Galaxies Active?)

        The WF/PC-2 was used to investigate the accretion onto massive 
black holes that are believed to be the energy source for AGN.  However, 
evidence for black holes in quiescent galaxies has also been reported.  Why 
are these galaxies inactive?  One possibility is that active galaxies are 
better at providing fuel to the nuclear region than quiescent 
galaxies.  Other possible fueling mechanisms such as ``bars-within-bars'' 
or nuclear spirals cannot be investigated from the ground because they are 
relatively small features in the ISM.  The observations were completed as 
planned.

    1.7 Completed Four Sets of STIS/CCD 8562 (Probing the Large Scale 
Structure: Cosmic Shear Observations)

        The Space Telescope Imaging Spectrograph (CCD) was used to probe 
the distortion of light bundles from distant galaxies, looking at the 
statistical properties of the intervening inhomogeneous {dark} matter 
distribution.  The proposal completed nominally.

    1.8 Completed STIS/CCD/MA2 8770 (The Nucleosynthesis of Boron - 
Benchmarks for the Galactic Disk)

        The Space Telescope Imaging Spectrograph (CCD and MA2) was used to 
determine boron (B) abundance.  In spite of several HST cycles of B 
abundance determinations, we do not know the true, ambient, present-day 
abundance of B.  Only two stars {with undepleted Li and Be} have been 
observed to derive the Population I true B abundance.  Past cycles have 
focused on {1} halo stars with low metallicity and {2} solar-type stars 
with Li and/or Be deficiencies.  In this proposal, the stellar abundances 
of B will be determined, measured from the B I 2497 Angstrom line from STIS 
echelle spectra, of main sequence F-G stars that have retained their full 
initial abundances of boron.  Our target stars are those for which 
ground-based observations show that beryllium is undepleted.  These new 
abundances will map evolution of the B abundance in the Galactic disk in 
the metallicity range from one-third solar up to solar.  Then the B, and 
previously determined Li and Be abundances, will be used to improve 
understanding of the nucleosynthesis of B.  There were no reported anomalies.

    1.9 Completed WF/PC-2 8587 (Stroemgren Photometry of Globular Clusters 
in M87: Breaking the Age- Metallicity Degeneracy)

        The WF/PC-2 was used to further demonstrate that the globular 
cluster {GC} systems of most, and possibly all, luminous galaxies show 
bimodal distributions in broadband color and, by implication, age and/or 
metallicity.  Whatever its origin, this bimodality {which is observed in 
giant galaxies that span a wide range in Hubble Type and local environment} 
must hold a fundamental clue to the process of galaxy formation.  The 
technique of this proposal hinges on the ability of Stroemgren photometry 
to decouple the effects of age and metallicity for large samples of GCs, 
and will provide the first strong constraints on the various galaxy 
formation models.  There were no reported problems.

    1.10 Completed STIS/CCD 8855 (Slit Wheel Repeatability)

        The Space Telescope Imaging Spectrograph (CCD) was used to test the 
repeatibility of the slit wheel by taking a sequence of comparison lamp 
spectra with grating G230MB {2697} and the three smallest long slits 
{52X0.2, 52X0.1, and 52X0.05}.  The proposal completed nominally.

    1.11 Completed WF/PC-2/STIS/CCD 8679 (Constraining the Age of the 
Oldest Stars from the White Dwarf Cooling Sequence in M4)

        The WF/PC-2 and the Space Telescope Imaging Spectrograph (CCD) were 
used to search for the oldest and hence coolest white dwarfs {WDs} in M4, 
the nearest Galactic globular cluster to the Sun.  New models for cooling 
hydrogen white dwarfs predict that their colors should become bluer, rather 
than redder, with increasing age. The goal is to test these models and at 
the same time constrain the age of M4.  The proposal completed with no 
problems.

2.0 FLIGHT OPERATIONS SUMMARY:

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

  Scheduled Re-acquisitions:  8
Successful:  8

    2.2 FHST Updates:
Scheduled: 18
Successful: 18

    2.3 Operations Notes:

        The SSR EDAC error counter was cleared four times per ROP SR-1A.

        Using ROP NS-5, SI C&DH errors were reset at 039/1937Z.

        An engineering status buffer error was reset at 039/2125Z as 
directed by ROP DF-18A.

        Per ROP IC-2, SSA transmitter #1 was turned on and off for the 
interval 039/2355Z to 040/0023Z.

3.0 SIGNIFICANT FORTHCOMING EVENTS:

        Continuation of normal science observations and calibrations.

/CAW