HUBBLE SPACE TELESCOPE

       DAILY REPORT #3095

PERIOD COVERED:  0000Z (UTC) 04/15/02 - 0000Z (UTC) 04/16/02

Daily Status Report as of 106/0000Z

1.0 OBSERVATIONS SCHEDULED AND ACCOMPLISHED:

    1.1 Completed Two Sets of STIS/CCD 8902 (Dark Monitor-Part 2)

        The Space Telescope Imaging Spectrograph (CCD) was used to monitor 
the darks.  No problems were reported.

    1.2 Completed Five Sets of ACS/WFC/HRC 8947 (Weekly Test)

        The Advanced Camera for Surveys (WFC and HRC) was used to perform 
basic tests to monitor, the read noise, the development of hot pixels and 
test for any source of noise in ACS CCD detectors.  As described in 
yesterday's report and HSTAR 8607, the acquisition for the third iteration 
of this proposal defaulted to fine lock back-up on one FGS only, possibly 
affecting three observations.  There were no other problems reported.

    1.3 Completed Three Sets of WF/PC-2 8937 (Cycle 9 Supplemental Darks pt2/3)

        The WF/PC-2 was used obtain three dark frames every day to provide 
data for monitoring and characterizing the evolution of hot pixels.  No 
problems were encountered.

    1.4 Completed Two Sets ofACS/WFC 9020 (Preliminary ACS Sensitivity)

        The Advanced Camera for Surveys (WFC) was used to observe a 
spectrophotometric standard star through each filter of each camera to 
assess the sensitivity of the instrument.  The star is placed at the center 
of the aperture, and two images are taken through each filter.  There were 
no reported problems.

    1.5 Completed STIS/CCD 8904 (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 in order to build up high-S/N superbiases and track the evolution 
of hot columns.  The proposal completed with no anomalous activity.

    1.6 Completed Two Sets of STIS/CCD 8905 (Read Noise Monitor)

        The Space Telescope Imaging Spectrograph (CCD) was used to measure 
the read noise of all the amplifiers {A, B, C, D} on the STIS CCD using 
pairs of bias frames.  Full frame and binned observations are made in both 
Gain 1 and Gain 4, with binning factors of 1x1, 1x2, 2x1 and 2x2.  All 
exposures are internals.  The proposal completed with no reported anomalies.

    1.7 Completed STIS/CCD 8907 (Spectroscopic Flats C10)

        The Space Telescope Imaging Spectrograph (CCD) was used to obtain 
CCD flats in the spectrographic mode.  There were no reported problems.

    1.8 Completed Two Sets of WF/PC-2 8939 (Cycle 10 Internal Monitor)

        The WF/PC-2 was used to calibrate the internal monitor, to be run 
weekly to monitor the health of the cameras.  No problems were encountered.

    1.9 Completed ACS/SBC 9008 (MAMA Initial Turn-on and Anomalous Recovery 
Procedure)

        The Advance Camera for Surveys (SBC) was used for the initial 
turn-on of the ACS MAMA detector and to permit recovery after an anomalous 
shutdown.  Anomalous shutdowns can occur as a result of bright object 
violations which trigger the Bright Scene Detection or Software Global 
Monitors.  Anomalous shutdowns can also occur as a result of MAMA hardware 
problems.  The Initial MAMA turn-on/recovery from anomalous shutdown 
consists of three tests: a signal processing electronics check, high 
voltage ramp-up to an intermediate voltage, and high voltage ramp-up to the 
full operating voltage.  During each of the two high voltage ramp-ups, 
diagnostics are performed during a dark ACCUM.  No problems were recorded.

    1.10 Completed STIS/CCD 9131 (Imaging the Host Galaxies of High 
Redshift Type Ia Supernovae)

        The Space Telescope Imaging Spectrograph (CCD) was used to complete 
the snapshot survey of distant galaxies of known redshift which hosted 
supernovae {SNe} of Type Ia found via the Supernova Cosmology Project 
{SCP}.  No problems were seen.

    1.11 Completed Two Sets of STIS/CCD 8908 (CCD Imaging Flats C10)

        The Space Telescope Imaging Spectrograph (CCD) was used to 
investigate flat-field stability over a monthly period.  The proposal 
completed with no reported problems.

    1.12 Completed STIS/CCD/MA1 9486 (What Excites LINERs: The Brilliant 
Case of NGC 3998)

        The Space Telescope Imaging Spectrograph (CCD and MA1) was used to 
observe LINER emission that is now known to occur in many galaxies at a 
variety of levels, with causes as diverse as old nuclear starbursts, 
cooling flows, accretion disks, and jets.  The early prototypes, including 
NGC 3998, belong to a distinct class of AGN-like LINERs with the most 
luminous line emission and powerful nuclear radio emission.  These LINERs 
have ionized gaseous disks on the scale of tens of parsecs, which have now 
been found to be in rotation about supermassive black holes.  The disks are 
apparently the outer parts of energy- releasing accretion disks.  Powerful 
new UV+optical emission line diagnostics have been developed to settle the 
long- standing debate over whether the gas is being photoionized or shock 
excited.  As described in yesterday's report and HSTAR 8607, the 
acquisition for the third iteration of this proposal defaulted to fine lock 
back-up on one FGS only, possibly affecting six observations.  There was no 
other reported anomalous activity.

    1.13 Completed STIS/MA2 9573 (NUV-MAMA Daily Dark Monitor)

        The Space Telescope Imaging Spectrograph (MA2) was used to perform 
daily monitoring of the NUV MAMA detector dark noise in order to monitor 
the effects of thermal changes on the NUV dark rate.  No problems occurred.

    1.14 Completed STIS/CCD/MA1 9067 (UV Detectability of Bright Quasars in 
the Sloan Fields)

        The Space Telescope Imaging Spectrograph (CCD and MA1) was used to 
take MAMA spectra of approximately 30 new, bright, high-redshift quasars in 
each of the next three cycles.  The observations completed with no reported 
problems.

    1.15 Completed STIS/CCD/MA1 9459 (The Response of the White Dwarf in WZ 
Sge to the Unexpected July 2001 Superoutburst)

        The Space Telescope Imaging Spectrograph (CCD and MA1) was used to 
observe WZ Sge, the most extreme dwarf nova and one of the closest known 
cataclysmic variables, that has undergone a superoutburst in July 2001 
after 22 years in quiescence.  Because of the uniqueness of this event, two 
DD proposals were approved, one to observe the outburst itself, and another 
for us to observe the early decline phase.  Here it is proposed to complete 
our fundamental study of the response of a dwarf nova system to an outburst 
by continuing our UV coverage of this most extreme outbursting system 
during its decline to quiescence.  This decline is expected to take more 
than 3 yrs, with the most dramatic changes occurring in the first 2 
years.  This once-in-a-lifetime chance to obtain high quality, high time 
{and spectral} resolution FUV data as the decline progresses into the 
critical transition from the disk- dominated phase to the bare white dwarf, 
provides an unique opportunity to study the response of the emerging white 
dwarf, whose chemical abundances, rotation and temperature variation with 
time bear the imprint of this extraordinary gigantic accretion event.  The 
proposal completed with no reported problems.

    1.16 Completed STIS/MA1/MA2 9120 (Planetary Nebulae In The LMC: A Study 
On Stellar Evolution And Populations)

        The Space Telescope Imaging Spectrograph (MA1 and MA2) was used to 
investigate the final phase of the evolution of low- and intermediate-mass 
stars, the Planetary Nebula {PN} ejection that is thought to provide the 
main source of carbon and nitrogen enrichment in galaxies.  The 
observations completed nominally with no reported problems.

    1.17 Completed STIS/MA2 8920 (Cycle 10 MAMA Dark Measurements)

        The Space Telescope Imaging Spectrograph (MA2) was used to perform 
the routine monitoring of the MAMA detector dark noise, and is the primary 
means of checking on health of the MAMA detectors systems through frequent 
monitoring of the background count rate.  The proposal completed with no 
reported anomalous activity.

    1.18 Completed STIS/CCD 9077 (Survey of the LMC Planetary Nebulae)

        The Space Telescope Imaging Spectrograph (CCD) was used to perform 
a snapshot survey of all known LMC planetary nebulae {PNe} in order to 
study the co-evolution of the nebulae and their central stars, and to probe 
the chemical enrichment history of the LMC.  There were no reported problems.

    1.19 Completed FGS/1 9034 (The Masses and Luminosities of Population II 
Stars)

        Fine Guidance Sensor #1R was used to observe the mass-luminosity 
relation {MLR} of Population II stars of which very little is currently 
known.  With the advent of the Hipparcos Catalogue, improved distances to 
many spectroscopic binaries known to be Pop II systems are now 
available.  After surveying the literature and making reasonable estimates 
of the secondary masses, we find 13 systems whose minimum separation should 
be larger than the resolution limit of FGS #1R.  The observations completed 
nominally.

    1.20 Completed WF/PC-2/STIS/CCD 9174 (Using Optically Faint Radio 
Sources to Pinpoint Dusty Proto-Galaxies)

        The WF/PC-2 and the Space Telescope Imaging Spectrograph (CCD) were 
used to observe a number of high redshift, dusty starburst galaxies that 
remain invisible in ground based observations in the Hubble Deep 
Field.  These galaxies appear as faint radio sources with bright 
submillimeter counterparts, demonstrating they are very dusty systems.  The 
luminosities of these galaxies suggest they are in the process of 
converting the bulk of their gas mass into stars, and will likely evolve 
into present day massive ellipticals.  The observations completed normally, 
with no reported problems.

    1.21 Completed STIS/CCD 9070 (A Census of Nuclear Star Clusters in 
Late-Type Spiral Galaxies: II. Spectroscopy and Stellar Populations)

        The Space Telescope Imaging Spectrograph (CCD) was used to 
investigate spiral galaxies that have a prominent star cluster in their 
dynamical center.  Statistics for cluster frequency, size, and luminosity 
remain incomplete.  The proposal completed as planned.

2.0 FLIGHT OPERATIONS SUMMARY:

    2.1 Guide Star Acquisitions:
       Scheduled Acquisitions: 12
    Successful: 12

  Scheduled Re-acquisitions:  5
    Successful:  5

    2.2 FHST Updates:
    Scheduled: 24
    Successful: 22

        Per HSTAR 8608, the full maneuver updates scheduled for 106/084931Z 
and 106/085216Z failed with error results indicating tracker #1 
failed.  The subsequent acquisition was successful.

    2.3 Operations Notes:

        Operations notes were utilized to:
                 Restore ACS flight software error limits.
                 Perform HSTAR documentation for FHST map/update failures.

        Using operations requests, the following actions were executed:
                 Clear ACS flight software error counter at 105/1343Z.
                 Genslew for proposal 9110 - slot 1 at 105/1428Z.
                 Clear ACS SBC event flag at 105/1543Z.
                 Set ACS SBC event flag to prevent high voltage turn-on at 
105/2013Z
(BALL expressed concerns that the SBC low voltage supply had not
been enabled long enough (>18 hours) to allow sufficient out-gassing
prior to high voltage operations).

        Per ROP RD-7A, ESTR re-conditioning was performed at 105/2039Z.

        The ephemeris table was uplinked at 106/0127Z, using ROP DF-07A.

        The engineering status buffer limit for SESBSLD was updated at 
106/0856Z as directed by ROP DF-18A.

3.0 SIGNIFICANT FORTHCOMING EVENTS:

        Battery #3 Capacity Test is scheduled to occur at approximately 
107/1130Z.

        An intercept SMS, the intercept point being approximately 
109/0354Z, is being prepared.  This SMS will recover NICMOS and then begin 
NICMOS Servicing Mission Orbital Verification (SMOV) activities.

        Continuation of SMOV and the gradual resumption of normal science 
observations and calibrations.

/CAW