HUBBLE SPACE TELESCOPE

   DAILY REPORT #2895

PERIOD COVERED:  0000Z (UTC) 06/15/01 - 0000Z (UTC) 06/18/01

Daily Status Report as of 169/0000Z

1.0 OBSERVATIONS SCHEDULED AND ACCOMPLISHED:

    1.1 Completed Seven Sets of WF/PC-2 8828 (Cycle 9 Supplemental Darks pt3/3)

        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 with no reported problems.

    1.2 Completed Three Sets of WF/PC-2 8592 (Pixel Microlensing of M87)

        The WF/PC-2 was used to undertake a pixel microlensing study of M87 
in order to: 1} probe the lower end of the M87 IMF via star-star lensing, 
2} possibly obtain the first evidence of Massive Compact Objects (MACHOs) 
in the halo of a galaxy other than our own, and 3} search for intracluster 
MACHOs.  The proposal completed nominally.

    1.3 Completed Three Sets of WF/PC-2 9085 (Measuring The Masses Of 
High-Z Quasar Host Galaxies)

        The WF/PC-2 was used to investigate the close link between 
black-hole mass and spheroid mass in both quiescent and active galaxies in 
the local universe.  Consequently black-hole and spheroid formation/growth 
are now viewed as intimately related processes, and establishing the mass 
of quasar host galaxies as a function of redshift is now seen as a key 
measurement in observational cosmology.  From the Cycle 7 NICMOS program, 
the best estimate to date of the mass evolution of the hosts of both 
radio-quiet and radio-loud quasars out to z ~eq 2 has been derived.  Under 
the assumption of passive stellar-population evolution our results are 
consistent with the black-hole/spheroid population being unchanged out to z 
~eq 2.  However, the crucial assumption of passive evolution needs to be 
tested.  All observations competed nominally.

    1.4 Completed WF/PC-2 8581 (A Search For Low-Mass Companions To 
Ultracool Dwarfs)

        The WF/PC-2 was used to search for very low-mass {VLM} companions 
to a complete sample of 120 late-M and L dwarfs, drawn mainly from the 
2MASS and SDSS surveys.  The primary goal is to determine the multiplicity 
of M < 0.1 M_odot dwarfs.  In particular, we aim to identify binary systems 
suitable for long-term astrometric monitoring and mass measurement, and 
systems with cool, sub-1000K companions.  The proposal completed with no 
reported problems.

    1.5 Completed WF/PC-2 8683 (Imaging Of Brightest Cluster Galaxies: The 
High End Of The Black Hole Mass Distribution)

        The WF/PC-2 was used to make kinematic black hole detections in 
galaxies to decide whether they indicate that the mass correlates with both 
optical luminosity and radio power.  The observation completed with no 
reported problems.

    1.6 Completed WF/PC-2 9115 (The Evolution of Extreme Gas Rich Galaxies)

        The WF/PC-2 was used to observe a recently discovered sample of the 
closest known low surface brightness, very gas-rich dwarf galaxies outside 
of the Local Group.  These galaxies represent an extreme star formation 
environment, where the fuel for star formation appears plentiful, the local 
environment {the Centaurus A group of galaxies} provides opportunities for 
tidally-induced star formation, and yet star formation appears to be 
surpressed {by two orders of magnitude} compared to other `typical' 
galaxies.  The goal is to understand the star formation history in this 
puzzling environment of low stellar density and high gas content.  By 
resolving the underlying stellar component, the observer will obtain 
critical information on the mean metallicity and star formation history of 
these galaxies.

    1.7 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.

    1.8 Completed WF/PC-2 8583 (Imaging Snapshots of Asteroids)

        The WF/PC-2 was used to obtain images of the fifty largest main 
belt asteroids that have favorable apparitions during cycle 9.  The images 
will be searched for companion bodies, as well as mineralogical variegation 
on the resolved main bodies.  There were no reported problems.

    1.9 Completed WF/PC-2 8604 (Stellar Populations Across the Small 
Magellanic Cloud (SMC) : History and Structure)

        The WF/PC-2 was used to investigate the structure and evolutionary 
history of the SMC by obtaining a series of 50 three-color snapshots of 
selected SMC regions.  With this polling of SMC field star properties, we 
will produce color-magnitude diagrams in the U, V and I bands which will 
reach V~23.5 in regions too crowded to be observed accurately from the 
ground.  The observations completed nominally.

    1.10 Completed WF/PC-2 9043 (Cepheid Distances to Early-type Galaxies)

        The WF/PC-2 was used to continue observations in the HST Key 
Project on the Extragalactic Distance Scale and the HST project on the 
"Calibration of Nearby Type Ia Supernovae'' that have greatly improved our 
knowledge of the Hubble Constant by providing a solid zero point for the 
Tully- Fisher {TF} relation and Type Ia Supernovae {SNIa}.  However, severe 
inconsistencies remain for distance estimators to early-type galaxies such 
as surface brightness fluctuations {SBF}, the planetary nebula luminosity 
function {PNLF}, the fundamental plane {FP}, and the globular cluster 
luminosity function {GCLF}.  As a result, the distance to the Virgo cluster 
core remains uncertain by as much as 20 determination is directly affected 
by a lingering 0.1 mag {5 uncertainty in the photometric calibration of the 
WFPC2.  Resolving these issues is essential not only to firm up the 
extragalactic distance scale, but also to understand the mass and velocity 
structure of the local universe. SBF in particular is emerging as the 
method of choice for mapping local velocity fields to 10, 000 kms because 
it offers an order of magnitude less Malmquist bias than TF, and SNIa are 
too rare to study large scale flows effectively.  This project will tighten 
the photometric calibration of the WFPC2, and provide a solid Cepheid 
calibration for SBF and PNLF.  The observations completed nominally.

    1.11 Completed WF/PC-2 9157 (Fundamental Properties Of L-Type Dwarfs In 
Binaries)

        The WF/PC-2 was used to characterize the physical properties of 
eight L-dwarfs in four binary systems.  The goal is to obtain astrometric, 
photometric and spectroscopic measurements of each component that will 
yield basic information on their atmospheric and dynamical properties.  The 
proposal completed nominally.

    1.12 Completed Five Sets of WF/PC-2 8824 (Decontaminations and 
Associated Observations Pt. 3/4)

        The WF/PC-2 was used for the monthly WFPC2 decons.  Also included 
are instrument monitors tied to decons: photometric stability check, focus 
monitor, pre- and post-decon internals {bias, intflats, kspots, & darks}, 
UV throughput check, VISFLAT sweep, and internal UV flat check.  There were 
no reported problems.

    1.13 Completed Four Sets of FGS/1 8731 (A High Angular Resolution 
Survey of the Most Massive Stars in the SMC)

        Fine Guidance Sensor #1 was used to conduct high angular resolution 
observations of some of the SMC's hottest and most luminous objects by 
conducting a comprehensive survey of nearly every spectral type in the 
upper portion of the HR diagram.  Binary or multiple star systems will be 
detected down to an unprecedented level, more than one order of magnitude 
better than possible with WFPC2.  The targets selected include a 
representative list of normal Main Sequence O-stars and their evolved 
descendents, namely supergiants, hypergiants, LBVs, and WRs, many of which 
have been previously observed by HST's spectrometers for purposes of 
cosmological calibrations.  The observations completed, and no problems 
were reported.

    1.14 Completed WF/PC-2 9045 (The Relationship Between Radio Luminosity 
and Radio-Loud AGN Host Galaxy Properties)

        The WF/PC-2 was used to determine the relationship between the 
properties of the host galaxies of radio-loud AGN and their radio 
luminosities.  Previous studies in this area with the HST have concentrated 
on the 3C sample which shows a tight correlation between luminosity and 
redshift, such that evolutionary effects cannot be distinguished from those 
depending upon radio luminosity.  Our sample of 46 radio galaxies at z ~ 
0.5 comes from four complete, low-frequency-selected samples of radio 
sources with differing flux limits.  Thus the total sample spans an 
unprecedented three orders of magnitude in radio luminosity at a fixed 
redshift interval.  The proposal completed with no reported problems.

    1.15 Completed Three Sets of WF/PC-2 9133 (Imaging of Gravitational Lenses)

        The WF/PC-2 was used to observe gravitational lenses that offer 
unique opportunities to study cosmology, galactic structure, galaxy 
evolution, quasar hosts and extinction.  They are also the only sample of 
galaxies selected on the basis of their mass rather than their luminosity 
or surface brightness.  While gravitational lenses can be discovered with 
ground-based optical and radio observatories, converting them from 
curiosities into scientific tools requires HST.  There were no reported 
anomalies.

    1.16 Completed Two Sets of WF/PC-2 8815 (Cycle 9 Earth Flats)

        The WF/PC-2 was used to monitor flatfield stability.  This proposal 
obtains sequences of Earth streak flats to construct high quality flat 
fields for the WF/PC-2 filter set.  These flat fields will allow mapping of 
the OTA illumination pattern and will be used in conjunction with previous 
internal and external flats to generate new pipeline superflats.  The 
proposal completed nominally.

2.0 FLIGHT OPERATIONS SUMMARY:

    2.1 Guide Star Acquisitions:
       Scheduled Acquisitions: 27
Successful: 27

  Scheduled Re-acquisitions: 15
Successful: 15

    2.2 FHST Updates:
Scheduled: 65
Successful: 64

        The update at 169 0831Z failed.

    2.3 Operations Notes:

        The Space Telescope Imaging Spectrograph remains in safe mode.

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

        Using ROP DF-18A, the engineering status buffer limits were 
adjusted on eight occasions.

        Operations personnel managed the WF/PC-2 ground system limits for 
the period 168/0119Z to 168/1340Z during a period of decontamination.

        A TTR was written when there was a required re-transmit during a 
486 load at 169/0745Z.

        When problems arose on CCS string "A" (see HSTAR 8246), real-time 
operations transferred to CCS string "G" at 169/0500Z.  Later, at 
169/0906Z, real-time operations returned to "A" string.

        The NSSC-1 status buffer was dumped and reset at 169/0854Z as 
directed by ROP NS-3.

3.0 SIGNIFICANT FORTHCOMING EVENTS:

        Continuation of normal science observations and calibrations.

/CAW