HUBBLE SPACE TELESCOPE

   DAILY REPORT #2867

PERIOD COVERED:  0000Z (UTC) 05/07/01 - 0000Z (UTC) 05/08/01

Daily Status Report as of 128/0000Z

1.0 OBSERVATIONS SCHEDULED AND ACCOMPLISHED:

    1.1 Completed Sixteen Sets of STIS/CCD 9248 (Probing the Large Scale 
Structure: Cosmic Shear Observations)

        The Space Telescope Imaging Spectrograph (CCD) was used to measure 
the distortion of light bundles from distant galaxies that probe the 
statistical properties of the intervening inhomogeneous {dark} matter 
distribution.  Its tidal gravitational field distorts the observable image 
shapes thereby causing a coherent ellipticity pattern {Cosmic Shear}.  The 
observations completed nominally.

    1.2 Completed STIS/CCD 8667 (Nuclear Stellar Disks in Early Galaxies: 
Black Hole Masses and Disk/Bar/Bulge Evolution)

        The Space Telescope Imaging Spectrograph (CCD) was used to image of 
an additional four E/SO galaxies to: {1} test whether the unusual 
M_bh/M_bulge ratio is typical of these nuclear disk galaxies and {2} search 
for additional ring/bar structures will help determine the source of the 
accreted material and the time sequence of the disk/bar/bulge/Black Hole 
fueling connection.  The observations completed with no reported anomalies.

    1.3 Completed Three Sets of STIS/CCD 8836 (Performance Monitor {Cycle 9})

        The Space Telescope Imaging Spectrograph (CCD) was used to measure 
the baseline performance and commandability of the CCD subsystem.  Only 
primary amplifier D was used.  Bias and Flat Field
exposures were taken in order to measure read noise, CTE, and 
gain.  Numerous bias frames were taken to permit construction of 
"superbias" frames in which the effects of read noise have been rendered 
negligible.  Full frame and binned observations were made, with binning 
factors of 2 x 1, 1 x 2, 2 x 2, 4 x 1, and 4 x 2.  Dark images were taken 
in 2x2 binning mode; 1x1 binning darks are being taken in the nominal CCD 
Dark Monitor.  The exercise completed nominally.

    1.4 Completed Four 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.

    1.5 Completed FGS/1 8586 (Observations of Astrophysically Important 
Visual Binaries)

        Fine Guidance Sensor #1 was used to continue the Cycle 7-8 
Long-Term project.  The program consists of annual or biannual WFPC2 or FGS 
observations of three visual binary stars that will ultimately yield 
fundamental astrophysical results, once their orbits and masses are 
determined.  Our targets are the following: {1} Procyon {P=41 yr}, for 
which our first WFPC2 images yielded an extremely accurate angular 
separation of the bright F star and its very faint white-dwarf 
companion.  There were no reported problems.

    1.6 Completed WF/PC-2 9244 (POMS Test Proposal: WFII Parallel Archive 
Proposal Continuation)

        The WF/PC-2 was used to perform a generic target version of the 
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 observations completed with no anomalous 
activity.

    1.7 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.

    1.8 Completed Two Sets of STIS/CCD 8864 (CCD Dark Monitor-Part 2)

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

    1.9 Completed Six Sets of WF/PC-2 8811 (Cycle 9 Standard Darks)

        The WF/PC-2 was used to obtain dark frames every week in order to 
provide data for the ongoing calibration of the CCD dark current rate, and 
to monitor and characterize the evolution of hot pixels.  Over an extended 
period these data will also provide a monitor of radiation damage to the 
CCDs.  The proposal completed with no reported problems.

    1.10 Completed WF/PC-2 8702 (The Most Elusive Nuclei of LMC Planetary 
Nebulae)

        The WF/PC-2 was used to carry out a SNAPSHOT survey of the faintest 
nuclei of planetary nebulae {PNe} in the LMC.  This program will be a 
crucial follow-on to a Cycle 8 SNAPSHOT of LMC Pne.  In thisa case the plan 
is to observe the faintest or most obscured nuclei to determine their 
evolutionary state to an accuracy not possible in the Galaxy.  These 
faintest central stars are predicted to be among the most massive nuclei, 
and owing to the typically advanced age of the surrounding nebulae, are the 
most sensitive discriminants for validating the post-AGB evolution 
timescales predicted by theory.  The observations completed with no 
reported problems.

    1.11 Completed STIS/CCD 8865 (Bias Monitor-Part 2)

        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 anomalous activity.

    1.12 Completed Two Sets of WF/PC-2 8585 (Cosmological Parameters from 
Type Ia Supernovae at High Redshift)

        The WF/PC-2 was used to measure the cosmological parameters, Omega, 
Lambda, and thus the curvature, Omega_k, using Type Ia supernovae {SNe Ia} 
as calibrated standard candles.  There were no reported problems.

    1.13 Completed Four Sets of STIS/CCD 8845 (Spectroscopic Flats C9)

        The Space Telescope Imaging Spectrograph (CCD) was used to obtain 
CCD flats in the spectroscopic mode.  The observations completed with no 
reported problems.

    1.14 Completed WF/PC-2 8812 (Cycle 9 Internal Monitor)

        The WF/PC-2 was used to obtain routine internal monitors for WFPC2 
in order to monitor the health of the cameras.  A variety of internal 
exposures are obtained in order to provide a monitor of the integrity of 
the CCD camera electronics in both bays {gain 7 and gain 15}, a test for 
quantum efficiency in the CCDs, and a monitor for possible buildup of 
contaminants on the CCD windows.  There were no reported problems.

    1.15 Completed WF/PC-2 8722 (Is Cir X-1 Associated with SNR G321.9- 0.3?)

        The WF/PC-2 was used to investigate Cir X-1, one of the most 
intriguing galactic X-ray sources.  It is a ~ 16.6 d variable X/radio 
source, a type I X-ray burster and a QPO emitter, which, in spite of an 
ambiguous optical counterpart classification, identifes it as an LMXB.  The 
source is embedded in a radio nebula, with finer structures protruding 
towards the centre of the nearby SNR G321.9-0.3. This prompted speculation 
about a connection between the two, with Cir X-1 possibly being a runaway 
binary originated from the supernova explosion.  There were no problems 
with this observation.

    1.16 Completed Three Sets of WF/PC-2 8682 (A Snapshot Study of 
0bservational Cosmology)

        The WF/PC-2 was used to examine the observational constraints on 
the cosmic star formation history that is currently among the most active 
fields in observational cosmology.  The most widely used tracer of the 
co-moving volume-averaged star formation rate {SFR} is the UV luminosity 
density, which early results found to peak at z~1- 2.  The apparent 
identification of the primary epoch of metal production and star formation 
in the Universe led to intense theoretical and observational 
interest.  Nevertheless, and remarkably for such a fundamental observation, 
little is known about the history of star formation in the Universe beyond 
its global average.  There were no reported anomalies.

    1.17 Completed Three Sets of 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.

2.0 FLIGHT OPERATIONS SUMMARY:

    2.1 Guide Star Acquisitions:
       Scheduled Acquisitions: 13
Successful: 13

        Per HSTAR 8207, the acquisition at 128/084014Z defaulted to fine 
lock backup on FGS-1 only when the scan step limit was exceeded on 
FGS-2.  Two proposals, each occurring during the period of the next report, 
were affected: STIS 9248 and WF/PC-2 8585.
  Scheduled Re-acquisitions:  5
Successful:  5

    2.2 FHST Updates:
Scheduled: 18
Successful: 18

    2.3 Operations Notes:

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

        NICMOS was recovered from the suspend state at 127/1405Z per an 
operations request.

        QDSCOSE (Earth Point COS) flagged out-of-limits red high at 
127/141805Z with a value of 0.31489 (limit is 0.3107).  This occurred 
during a term exp.  The parameter returned to normal range at 
127/141905Z.  HSTAR 8206 was written.

        The HST ephemeris was uplinked at 128/0053Z.

3.0 SIGNIFICANT FORTHCOMING EVENTS:

        The gyro #5 power cycle test is scheduled to begin at approximately 
128/1200Z.

        Continuation of normal science observations and calibrations.

/CAW