HUBBLE SPACE TELESCOPE

       DAILY REPORT #2956

PERIOD COVERED:  0000Z (UTC) 09/13/01 - 0000Z (UTC) 09/14/01

Daily Status Report as of 257/0000Z

1.0 OBSERVATIONS SCHEDULED AND ACCOMPLISHED:

    1.1 Completed Five 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.  As described in HSTAR 8339 and 2.1, the 
acquisition for the third iteration of this proposal defaulted to fine lock 
backup on one FGS only, possibly affecting one observation.  Otherwise, the 
observations completed with no further anomalous activity.

    1.2 Completed Two Sets of STIS/CCD 8901 (Dark Monitor-Part 1)

        The Space Telescope Imaging Spectrograph (CCD) was used to monitor 
the darks.  There was no anomalous activity.

    1.3 Completed Four Sets of WF/PC-2 8936 (Cycle 10 Supplemental Darks Pt1/3)

        The WF/PC-2 was used to perform a dark calibration program that 
obtains three dark frames every day to provide data for monitoring and 
characterizing the evolution of hot pixels.  The proposal completed with no 
reported problems.

    1.4 Completed WF/PC-2 8584 (Calibrating the Metallicity Dependence of 
the Cepheid PL Relation)

        The WF/PC-2 was used to determine the uncertainty in the metal 
abundance dependence of the Cepheid PL relation that remains as one of the 
largest sources of systematic error in the Cepheid distance scale and in 
the extragalactic distance scale as a whole.  There were no reported problems.

    1.5 Completed STIS/CCD 9285 (POMS Test Proposal: STIS Non-scripted 
Parallel Proposal Continuation III)

        The Space Telescope Imaging Spectrograph (CCD) was used to make low 
galactic latitude, non-scripted parallel observations as part of a POMS 
test proposal.  The observations were completed as planned, and no 
anomalies were reported.

    1.6 Completed STIS/CCD 9051 (Identifying Damped Lyman-alpha Galaxies at 
z~1)

        The Space Telescope Imaging Spectrograph (CCD) was used to look for 
samped Lyman-alpha absorption systems that contain the bulk of the neutral 
gas in the Universe in the redshift range z = 0.5 - 5, yet the nature of 
the galaxies responsible for the absorption is not well understood.  Only 
recently have observers found more than a handful of damped absorbers at 
redshifts z < 1.5.  Using the FIRST Bright Quasar Survey {FBQS}, with over 
a 1000 quasars, the proposers have undertaken a survey to build a complete 
picture of he nature of the galaxies responsible for damped Lyman-alpha 
absorption systems at z~1 and to double the sample size at this 
redshift.  No problems were encountered.

    1.7 Completed STIS/CCD 8903 (Bias Monitor - Part 1)

        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.  There were no problems.

    1.8 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 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.

    1.9 Completed STIS/CCD 9136 (T Tauri Star Coronagraphic Survey: A PMS 
Protoplanetary Disk Census)

      The Space Telescope Imaging Spectrograph (CCD) was used to observe 
pre-main sequence solar-mass stars, the T Tauri stars that Millimeter and 
IR studies suggest at least 50 percent have circumstellar disks similar to 
the disk from which our planetary system formed.  High spatial resolution, 
high dynamic range imaging of such systems will map the spatial 
distribution of material around the star, constraining the disk sizes and 
inclinations, and provide a first assessment of when structure in the disk, 
such as cleared central zones and annuli, which has been linked to planet 
formation, develops.  As described in HSTAR 8339 and 2.1, the acquisition 
for this proposal defaulted to fine lock backup on one FGS only, possibly 
affecting five observations.  Otherwise, all observations completed without 
incident.

    1.10 Completed WF/PC-2 8941 (Cycle 10 UV Earthflats)

        The WF/PC-2 was used to monitor flat field stability by obtaining 
sequences of earth streak flats to improve the quality of pipeline flat 
fields for the WFPC2 UV filter set.  As described in HSTAR 8339 and 2.1, 
the acquisition for this proposal defaulted to fine lock backup on one FGS 
only, possibly affecting two observations.  Otherwise, the proposal had no 
other problems.

    1.11 Completed Three 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.

    1.12 Completed STIS/CCD 8911 (Sparse-Field CTE External C10)

        The Space Telescope Imaging Spectrograph (CCD) was used to 
determine the derivation of accurate coefficients which can be used to 
correct low count level data {both imaging and spectroscopy} for 
nonlinearity/CTE effects.  Dependences on x-position, background sky level, 
and time dependence will be quantified in addition to accurate 
determination of intensity and y-position effects in a third epoch and to 
higher accuracy than previously determined.  The proposal completed with no 
reported problems.

    1.13 Completed Three Sets of WF/PC-2 9249 (POMS Test Proposal: WFII 
Backup Parallel Archive Proposal II)

        The WF/PC-2 was used to execute a POMS test proposal designed to 
simulate scientific plans.  The proposal completed with no reported problems.

    1.14 Completed WF/PC-2 9160 (Disks and Envelopes of Nearby Nebulous 
Young Stellar Objects: A Snapshot Survey)

        The WF/PC-2 was used to perform a snapshot survey of nearby 
nebulous young stellar objects to study the detailed morphology of the 
their disks and envelopes and probe the effect of inclination on the 
infrared spectral energy distribution of disk/envelope systems.  The 
proposal completed as planned.

    1.15 Completed STIS/CCD/MA2 9040 (Baryons In Intermediate Redshift {Z > 
1} OVI Absorbers)

        The Space Telescope Imaging Spectrograph (CCD and MA2) was used to 
search for intervening OVI absorption systems in two further extremely UV 
bright intermediate redshift QSOs {HS 0747 + 4259, z = 1.9, V = 15.6; HS 
0818+2554, z = 1.5, V = 15.4} using the STIS E230M Echelle mode.  The 
scientific aim is to measure the baryonic fraction in the warm-hot 
intergalactic medium at redshifts 1 <=q z <=q 1.8.  Present existing data 
on HE 0515-4414 taken also with STIS E230M seem to indicate that the 
baryonic fraction at z = 1.5 is lower by a factor of ~ 15 than the high 
value found by Tripp et al. {2000} for z < 0.3.  Our results need to be 
confirmed by more lines of sight, and we plan to test hierarchical 
structure formation models which predict a rapid evolution between z = 1.5 
and z = 0.  The observations completed as planned with no reported 
anomalous activity.

2.0 FLIGHT OPERATIONS SUMMARY:

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

        Per HSTAR 8339, the acquisition at 256/115341Z defaulted to fine 
lock backup on FGS-1 when the scan step limit was exceeded on FGS-3.  The 
science proposals detailed in 1.1, 1.9 and 1.10 may have been affected.
  Scheduled Re-acquisitions:  6
Successful:  6

    2.2 FHST Updates:
Scheduled: 17
Successful: 17

    2.3 Operations Notes:

        The SSR EDAC error counter was cleared twice, per ROP SR-1A.

        A TTR Was generated when there was an engineering data loss from 
256/1009Z until 256/1029Z due to bad weather.

        An SSR engineering record was performed at 256/1032Z per ROP SR-4A.

        The NSSC-1 status buffer was dumped and reset at 257/0507Z as 
directed by ROP NS-3.

3.0 SIGNIFICANT FORTHCOMING EVENTS:

        Continuation of normal science observations and calibrations.

/CAW