HUBBLE SPACE TELESCOPE

       DAILY REPORT #3105

PERIOD COVERED:  0000Z (UTC) 04/29/02 - 0000Z (UTC) 04/30/02

Daily Status Report as of 120/0000Z

1.0 OBSERVATIONS SCHEDULED AND ACCOMPLISHED:

    1.1 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.  This program will be 
executed at least once a day for the entire lifetime of ACS.  There were no 
problems reported.

    1.2 Completed Two Sets of NICMOS/1/2/3 8944 (Filter Wheel/Mechanisms 
Mini-Functional Test)

        The Near Infrared Camera and Multi-Object Camera (NIC1, NIC2 and 
NIC3) was used to perform an early engineering test to verify the 
aliveness, functionality, operability, and electro-mechanical calibration 
of the NICMOS filter wheel motors and assembly.  This was the first use of 
the NICMOS filter wheel mechanisms since they were disabled by ground 
command in January, 1999.  This test was designed to obviate concerns over 
possible deformation or breakage of the fitter wheel "soda-straw" shafts 
due to excess rotational drag torque and/or bending moments which may be 
imparted due to changes in the dewar metrology from warm-up/cool-down.  No 
anomalous incident occurred.

    1.3 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.

    1.4 Completed Four 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.

    1.5 Completed Five Sets of WF/PC-2 8935 (Cycle 10 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.

    1.6 Completed STIS/CCD 9110 (A Search for Kuiper Belt Object Satellites)

        The Space Telescope Imaging Spectrograph (CCD) was used to 
investigate whether the large number of collisions thought to have taken 
place in the primordial Kuiper belt suggest that many Kuiper belt objects 
{KBOs} could have suffered binary-forming collisions similar to that which 
formed the Pluto -- Charon binary.  Detection of such KBO satellites would 
allow measurement of  KBO masses, would help to understand the past 
collisional environment of the Kuiper belt, and would give a context to the 
otherwise unique-seeming formation of the Pluto -- Charon binary.  The 
proposal completed with no reported problems.

    1.7 Completed 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.

    1.8 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.

    1.9 Completed STIS/MA1 8922 (FUV-MAMA Cycle 10 Flats)

        The Space Telescope Imaging Spectrograph (MA1) was used to obtain 
FUV-MAMA observations of the STIS internal Krypton lamp to construct an FUV 
flat applicable to all FUV modes.  No problems were encountered.

    1.10 Completed Two Sets of NICMOS/1/2/3 8945 (Cooling System Monitoring)

        The Near Infrared Camera and Multi-Object Camera (NIC1, NIC2 and 
NIC3) was used 1) to measure NICMOS detector performance during the 
cool-down and steady state operation of the NCS. 2}. to demonstrate 
stability {+/-0.1K} of the NICMOS detector temperature at the optimal 
science operating temperature. and 3}.to demonstrate repeatability {+/-0.1 
K} of NICMOS detector temperature following changes from the optimal 
science operating temperature.  No problems were encountered.

    1.11 Completed WF/PC-2 9258 (Observatory Focus Monitor)

        The WF/PC-2 was used to more accurately define the HST focus.  The 
HST focus drifts slowly and shows evidence of undergoing slips of a few 
microns at random times.  The rate of the WF/PC-2 monitoring program is 
insufficient to track and/or understand OTA behavior in order to request 
timely and appropriate Secondary Mirror corrections.  There were no 
reported problems.

    1.12 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.

    1.13 Completed STIS/CCD 8900 (Performance Monitor)

        The Space Telescope Imaging Spectrograph (CCD) was used to measure 
the baseline performance and commandability of the CCD subsystem.  All 
exposures are internals.  The observations completed normally.

    1.14 Completed STIS/CCD/WF/PC-2/ACS/WFC/HRC 9574 (Focus Monitor)

        The Space Telescope Imaging Spectrograph (CCD), WF/PC-2 and the 
Advanced Camera for Surveys (WFC and HRC) were used to monitor HST 
focus.  In principle ACS/HRC should provide superior capability for 
monitoring the HST focus, but since most of the HST science will shift to 
ACS in Cycle 11 trending observations are initiated with this program to 
establish the focus of WFPC2/PC1 {and hence HST} and ACS/HRC {and WFC to a 
lessor degree} using exposures over full orbits that are taken in 
parallel.  No problems were reported.

    1.15 Completed Four Sets of STIS/CCD 9317 (Pure Parallel Imaging 
Program: Cycle 10)

        The Space Telescope Imaging Spectrograph (CCD) was used to perform 
the default archival pure parallel program for STIS during cycle 10.  There 
were no reported problems.

    1.16 Completed Two Sets of ACS/WFC 9575 (Default {Archival} Pure 
Parallel Program)

        The Advanced Camera for Surveys (WFC) was used to test ACS pure 
parallels in POMS.  There were no reported problems.

    1.17 Completed Two Sets of WF/PC-2 9180 (Gamma-ray Burst Progenitors: 
Probing Their Environment)

        The WF/PC-2 was used to perform a target of opportunity observation 
of gamma ray burster (GRB), GRB-011121.   GRB astronomy is a field maturing 
at a phenomenal rate.  Three important new observational and theoretical 
discoveries, formulated over the last twelve months, allow the proposer to 
address new, and in many cases, more sophisticated questions than could 
have been posed previously.  These developments: the discovery of X-ray 
lines in GRB 991216; the observation that N_H as deduced from X-ray 
afterglow are one to two orders of magnitude larger than the dust 
extinction inferred from optical afterglow; and the growing realization 
that the afterglow emission may exhibit features of dust echoes, appear to 
offer unexpected and new diagnostics that will directly inform us about the 
progenitor, the circum-progenitor material and the immediate interstellar 
environs.  There were no reported problems.

    1.18 Completed Two Sets of STIS/CCD 9088 (Next Generation Spectral 
Library of Stars)

        The Space Telescope Imaging Spectrograph (CCD) was used to produce 
a "Next Generation'' Spectral Library of 600 stars for use in modeling the 
integrated light of galaxies and clusters by using the low dispersion UV 
and optical gratings of STIS.  The library will be roughly equally divided 
among four metallicities, very low {Fe/H < -1.5}, low {-1.5 < Fe/H < -0.5}, 
near-solar {-0.5 < Fe/H < 0.1}, and super-solar {Fe/H > 0.1}, well-sampling 
the entire HR-diagram in each bin.  Such a library will surpass all extant 
compilations and have lasting archival value, well into the Next Generation 
Space Telescope era.  No problems occurred.

    1.19 Completed ACS/WFC 9029 (Grism/Prism Performance Check)

        The Advance Camera for Surveys (WFC) was used to observe a 
Wolf-Rayet star and a White Dwarf the grism of both the Wide Field and 
eventually the High Resolution Channels to measure: 1} the dispersion of 
the grism and its field dependence; 2} the grism throughput and its field 
dependence; 3} the frequency of the flat field variation {L-flat} as a 
function of wavelength; 4} the fringe pattern at longer wavelengths as a 
function of position on the chip.  These measurements will be carried out 
at several positions on the chip including the centre and the corners of 
the WFC and HRC chips.  All observations completed without incident.

    1.20 Completed WF/PC-2 9318 (POMS Test Proposal: WFII Parallel Archive 
Proposal Continuation)

        The WF/PC-2 was used to perform the generic target version of the 
WFPC2 Archival Pure Parallel program.  The program was used to take 
parallel images of random areas of the sky, following the recommendations 
of the Parallels Working Group.  There were no reported problems.

    1.21 Completed STIS/MA2 8923 (FUV-MAMA Cycle 10 Flats)

        The Space Telescope Imaging Spectrograph (MA2) was used to obtain 
FUV-MAMA observations of the STIS internal Krypton lamp to construct an FUV 
flat applicable to all FUV modes.  No problems were encountered.

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

        The Space Telescope Imaging Spectrograph (CCD and MA2) was used to 
perform daily monitoring of the NUV MAMA detector dark noise, monitoring 
the effects of thermal changes on the NUV dark rate.  No anomalous activity 
was noted.

2.0 FLIGHT OPERATIONS SUMMARY:

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

  Scheduled Re-acquisitions:  5
    Successful:  5

    2.2 FHST Updates:
    Scheduled: 22
    Successful: 22

    2.3 Operations Notes:

        ROP SR-1A was used to clear the SSR-1 EDAC error counter at 
119/1422Z and to reset the TRI module at 119/1912Z.

        Per an operations request, the gyro reconfiguration to take Gyo #1 
out of the control loop and configure to a 342 gyro configuration proceeded 
nominally starting at 119/1612Z.  Gyro #1 was removed from the control law 
shortly thereafter and powered off at 119/1622Z.  PSEA configuration memory 
and gyro safing tests were reconfigured by 119/1645Z.  A bias update was 
performed to remove any residual drift at 119/1935Z.  The first Guide Star 
Acquisition following the reconfiguration, at 119/2020Z, was successful.

        Another NICMOS filter wheel test, which began at 119/1755Z as 
directed by an operations request, performed as expected with results 
closely matching results obtained in 1997.  Another such test will be 
performed today.

        The ephemeris table was uplinked at 120/0004Z per ROP DF-07A.

        A TTR was written for a required re-transmit at 120/0846Z during a 
486 load.  Using ROP DF-18A, the CCS engineering status buffer limits were 
adjusted at 120/0847Z.

3.0 SIGNIFICANT FORTHCOMING EVENTS:

        The first release of Advanced Camera for Surveys (ACS) images will 
be released today at 1:00 p.m. in the NASA Headquarters auditorium.

        Continuation of Servicing Mission Orbital Verification and the 
gradual resumption of normal science observations and calibrations.

/CAW