HUBBLE SPACE TELESCOPE

   DAILY REPORT #2856

PERIOD COVERED:  0000Z (UTC) 04/20/01 - 0000Z (UTC) 04/23/01

Daily Status Report as of 113/0000Z

1.0 OBSERVATIONS SCHEDULED AND ACCOMPLISHED:

    1.1 Completed Five 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.

    1.2 Completed Six Sets of STIS/CCD 8591 (The Smallest Nuclear Black Holes)

        The Space Telescope Imaging Spectrograph (CCD) was used to observe 
small nuclear black holes which are the last major unexplored part of BH 
parameter space, searching for the smallest BHs that HST can possibly 
find.  The proposal completed with no reported anomalies.

    1.3 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.

    1.4 Completed Five 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.

    1.5 Completed Three Sets of 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.

    1.6 Completed WF/PC-2 8703 (A Spectacular Post-Starburst Quasar and the 
AGN--Starburst Connection)

        The WF/PC-2 was used to perform broad-band imaging of the 
spectacular post- starburst quasar UN J1025-0040 {V=19, z=0.634}.  The 
optical spectrum is a chimera, dominated in the blue by light from a 
quasar, and dominated in the red by light from a 400-Myr-old starburst with 
a mass possibly as much as 10^11 M_SUN.  The total energy budget of both 
sources appears similar, 10^11.6 L_SUN.  The extended fuzz of the host 
galaxy is asymmetric toward a nearby companion {dominated by an 800-Myr-old 
starburst}, signifiying some kind of interaction.  There were no reported 
problems.

    1.7 Completed Two Sets of FGS/1 9240 (Astrometric Mass Determination of 
an Extrasolar Planet Candidate)

        Fine Guidance Sensor-1R was used to perform astrometric 
observations that will allow a quick measure of the sky-plane motion of 55 
Cancri, a G star with an Msin{i} = 0.9 MJ radial velocity companion with a 
14 day period.  By using 7 pairs of visits, where each visit within a pair 
has the same parallax factor, we will be able to accurately determine the 
stars's proper motion.  The reflex motion of the star, due to its orbit 
about the star-companion barycenter, will manifest itself as a systematic 
residual to the measured proper motion if the companion is sufficiently 
massive.  There were no reported problems.

    1.8 Completed Seventeen Sets of 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.

    1.9 Completed Two 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.

    1.10 Completed STIS/MA2 8843 (Cycle 9 MAMA Dark Measurements)

        The Space Telescope Imaging Spectrograph (MA2) was used to perform 
the routine monitoring of the MAMA detector dark noise.  The proposal 
completed nominally.

    1.11 Completed WF/PC-2 8712 (The Wind Accretion Wake In A Detached 
Binary System)

        The WF/PC-2 was used to observe RW Hya {= HD 117970}, the only 
known detached binary system, where direct observational evidence for wind 
accretion onto a white dwarf is found.  UV
observations will enable the investigator to advance knowledge in a field 
which has for long had to remain a theoretical subject.  RW Hya is an 
eclipsing system containing a mass-losing M-giant and a hot white dwarf on 
circular orbits {370 days}.  The observation completed with no reported 
problems.

    1.12 Completed Six 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.

    1.13 Completed Three Sets of 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.

    1.14 Completed Three Sets of WF/PC-2 8677 (Extragalactic Novae: the 
Maximum Magnitude - Rate of Decline Relation in NGC 4472)

        The WF/PC-2 was used to accomplish two goals: {1} to provide the 
first homogeneous observational constraints on theoretical models for novae 
outbursts; and {2} to assess the reliability of novae as standard candles 
by using WFPC2 to collect well sampled light curves for 20-50 novae in the 
supergiant elliptical galaxy NGC 4472, the brightest galaxy within 30 
Mpc.  Both the length of the observing window and the temporal sampling of 
the observations are specifically designed to ensure that the novae peak 
magnitudes and decline rates are measured accurately.  These data will be 
used to construct the first `Maximum Magnitude versus Rate of Decline' 
{MMRD} relation for a galaxy beyond the Local Group.  This relation is not 
only a potentially powerful standard candle, but its shape and dispersion 
are directly linked to physical parameters which govern the physics of 
novae outbursts such as the white dwarf mass, temperature and mass 
accretion rate.  The proposal completed with no reported problems.

    1.15 Completed WF/PC-2 8602 (A Snapshot Survey of the Sites of Recent, 
Nearby Supernovae)

        The WF/PC-2 was used to conduct a snapshot survey in V and I of the 
sites of the nearby SNe, which have precisely known positions, to obtain 
high-resolution information on their local environment.  The proposal 
completed with no reported problems.

    1.16 Completed STIS/CCD/MA1 8693 (Interstellar Boron & Oxygen 
Abundances in the Cep OB2 Association: Probing)

        The Space Telescope Imaging Spectrograph (CCD and MA1) was used to 
investigate a specific nuclear process associated with core-collapse 
supernovae that involves the inelastic scattering of neutrinos {produced as 
a result of the core collapse} off of abundant nuclei in the outer layers 
of the dying star.  Two relatively low-abundance elements, boron and 
fluorine, have been suggested to owe some uncertain fraction of their 
cosmic abundances to this process.  In the case of boron, the dominant 
isotope is ^11B, and neutrinos interacting with ^12C can lead to its 
synthesis.  Fluorine-19 is the only stable F isotope and it can be produced 
by neutrino scattering, removing a proton from ^20Ne.  Competing processes 
can also synthesyze these elements: cosmic-ray spallation reactions for B 
and shell He-burning in AGB stars for F.  In order to gauge the importance 
of neutrino nucleosynthesis in the chemical evolution of the Galaxy, we 
will determine interstellar B and O abundances in the gas associated with 
the Cep OB2 association {using the B II 1362Angstrom and O I 1356Angstrom 
lines}.  These results will be combined with observations of interstellar F 
I along the same lines-of-sight obtained with FUSE {fluorine can only be 
compared directly to boron using interstellar lines and interstellar F is 
only observable with FUSE}.  The derived F/O and F/B ratios in Cep OB2 will 
allow us to determine the relative importance of neutrino nucleosynthesis 
to the origins of B and F.  The proposal completed with no reported problems.

    1.17 Completed Two Sets of 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.

    1.18 Completed WF/PC-2 8059 (POMS Test Proposal: Targeted Parallel 
Archive Proposal)

        The WF/PC-2 was used to observe the parallel opportunities 
available in the neighborhood of bright galaxies are treated in a slightly 
different way from the normal pure parallels.  Local Group galaxies offer 
the opportunity for a closer look at young stellar 
populations.  Narrow-band images in F656N can be used both to identify 
young stars via their emission lines, and to map the gas distribution in 
star-forming regions.  The observations completed nominally.

    1.19 Completed STIS/CCD/MA1/MA2 8691 (Calibrating the Cosmic Meter 
Stick: The Distance to the LMC Using Eclipsing Binaries)

        The Space Telescope Imaging Spectrograph (CCD, MA1 and MA2) was 
used to measure the LMC distance which is crucial for the calibration of 
the Cosmic Distance Scale.  The observations completed with no reported 
problems.

    1.20 19 Completed FGS/1R 8832 (Long Term Monitoring in Position Mode)

        Fine Guidance Sensor-!R was used to observe the relative positions 
of stars in a standard cluster at a fixed telescope pointing and 
orientation coordinates.  The evolution of rhoA and kA were monitored and 
calibrated to preserve the astrometric integrity of the FGS.  It is well 
known for our experience with FGS3, and later with FGS1r, that an FGS 
experiences long term evolution, presumably due to disorption of water from 
the instrument's graphite epoxy composites.  This manifests principally as 
a change in the plate scale and secondarily as a change in the 
distortions.  The proposal completed nominally, with no reported problems.

    1.21 Completed WF/PC-2 8816 (Cycle 9 UV Earthflats)

        The WF/PC-2 was used to obtain sequences of Earth streak flats to 
improve the quality of pipeline flat fields for the WFPC2 UV filter set and 
in order to monitor flat field stability.  There were no reported problems.

    1.22 Completed 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.

    1.23 Completed STIS/MA1 8721 (An UV Imaging Survey of IR-Bright Star- 
Forming Galaxies)

        The Space Telescope Imaging Spectrograph (MA1) was used to carry 
out a UV {~1, 600 Angstrom} snapshot imaging survey of all the actively 
star-forming galaxies detected by ISO at Lambda>170 Mum and closer than 
cz=9000 km/s.  The sample covers a large region in the parameter's space of 
morphology, luminosity, metallicity, and star formation intensity.  There 
were no reported anomalies.

    1.24 Completed STIS/CCD 8572 (Identifying Normal Galaxies at 1.3 < z < 2.5)

        The Space Telescope Imaging Spectrograph (CCD) was used to perform 
studies of faint, distant galaxies.  It is now possible to observe hundreds 
of galaxies out to z=1 and in the range 3 < z < 4.5, yet the redshift range 
1 < z <3 remains largely unexplored.  No problems were noted.

2.0 FLIGHT OPERATIONS SUMMARY:

    2.1 Guide Star Acquisitions:
       Scheduled Acquisitions: 30
Successful: 30

  Scheduled Re-acquisitions: 17
Successful: 17

    2.2 FHST Updates:
Scheduled: 63
Successful: 63

    2.3 Operations Notes:

        The SSR EDAC error counter was cleared eleven times, using ROP SR-1A.

        The STIS MCE-1 reset at 112/045437Z while the low voltage was on 
and while in an SAA interval.  The STIS flight software was then reset at 
112/0625Z as directed by ROP NS-12.  MAMA-1 was recovered at 112/1535Z when 
the high voltage was turned on via normal SMS commanding.

3.0 SIGNIFICANT FORTHCOMING EVENTS:

        Continuation of normal science observations and calibrations.

/CAW