HUBBLE SPACE TELESCOPE

   DAILY REPORT #2817

PERIOD COVERED:  0000Z (UTC) 02/26/01 - 0000Z (UTC) 02/27/01

Daily Status Report as of 058/0000Z

1.0 OBSERVATIONS SCHEDULED AND ACCOMPLISHED:

    1.1 Completed STIS/MA2 8867 (Gamma-Ray Bursts: Discovering The 
Progenitors And Understanding The Explosion)

        The Space Telescope Imaging Spectrograph (MA2) was used to observe 
a target-of-opportunity gamma-ray burster, GRB010222.  Gamma-ray burst 
astronomy, one of the most active and exciting frontiers in astrophysics, 
is now entering a critical stage -- with dramatic leaps in understanding of 
these events, as well as new discoveries.  Improvements in triggering and 
positioning accuracy provided by the SAX and HETE-2 gamma-ray satellites 
will allow entirely new classes of events to be studied.  Given the recent 
progress in this field, the proposers are now in a position to design 
precision, broadband measurements that can provide quantitative information 
on the as-yet unknown energy sources, the explosion geometry, and the 
surrounding medium.  In particular, the growing evidence of an intimate 
connection between SNe and GRBs can be definitively tested.  The proposal 
completed with no reported problems.

    1.2 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.

    1.3 Completed Three 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.

    1.4 Completed Two Sets of STIS/CCD 8837 (CCD Dark Monitor-Part 1)

        The Space Telescope Imaging Spectrograph (CCD) was used to monitor 
the darks.  The proposal completed with no reported problems.

    1.5 Completed Eight Sets of STIS/CCD 8562 (Probing the Large Scale 
Structure: Cosmic Shear Observations)

        The Space Telescope Imaging Spectrograph (CCD) was used to probe 
the distortion of light bundles from distant galaxies, looking at the 
statistical properties of the intervening inhomogeneous {dark} matter 
distribution.  As described in the previous report and HSTAR 8088, an 
acquisition and re-acquisition for the third and fourth iterations of this 
proposal failed and, as a result, all observations in those iterations were 
lost.  Otherwise, the proposal completed nominally.

    1.6 Completed 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.

    1.7 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 WF/PC -2 8177 (Investigating Type Ia Supernovae and an 
Accelerating Universe)

        The WF/PC-2 was to be used to obtain rest frame U and B photometry 
for four z~ 0.85 Supernova (SN) Ia.  As described in the previous report 
and HSTAR 8088, an acquisition and re-acquisition for this proposal failed 
and, as a result, all observations were lost.

    1.9 Completed Four 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.  As described in the previous report and HSTAR 8088, an acquisition 
and re-acquisition for the first iteration of this proposal failed and, as 
a result, all observations in that iterations were lost.  Otherwise, the 
proposal completed with no further reported problems.

    1.10 Completed WF/PC-2 8598 (Snapshot Survey of Extended OIIl Lambda 
5007Angstrom Emission in Seyfert Galaxies)

        The WF/PC-2 was used for a snapshot survey of narrow band OIII 
Lambda 5007Angstrom images for a well defined sample of 88 Seyfert galaxies 
{29 Seyfert 1s and 59 Seyfert 2s}, 18 of which already have data in the 
archive, selected from a mostly isotropic property, the 60Mum flux.  These 
data will be used: 1} to determine the origin of the misalignment between 
the accretion disk axis and the host galaxy plane axis, which can be due to 
mergers with other galaxies, or by the self induced radiation warping; 2} 
to compare the size and shape of the Narrow Line Regions (NLR) of Seyfert 
1s and Seyfert 2s, and to study the frequency of conically shaped NLR in 
Seyfert galaxies, which are usually unresolved from ground-based 
observations; and 3} estimate the importance of shocks to the ionization of 
the NLR.  The observations completed with no reported problems.

    1.11 Completed STIS/CCD 8838 (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.  The proposal completed nominally.

    1.12 Completed WF/PC-2 8632 (A UV Atlas of Nearby Galaxies)

        The WF/PC-2 was used to perform a snapshot survey of local galaxies 
at UV wavelengths with the F300W filter.  The aim of the project is to 
build a reference UV Atlas of normal galaxies, whose optical images are 
well known, with the highest possible degree of information, covering all 
the morphological types and luminosity classes.  The proposal completed 
normally.

    1.13 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

    1.14 Completed STIS/CCD 8639 (The Origin of Gaseous Outflows in Active 
Galaxies)

        The Space Telescope Imaging Spectrograph (CCD) was used to obtain 
images, previously observed by WF/PC-2, of the ionized gas in the Circinus 
galaxy, a nearby Seyfert 2.  The previous images reveal that the nuclear 
high excitation gas is ``V-shaped'' and represents the inner part of the 
``ionization cone'' seen previously on much larger scales in ground-based 
observations. These images suggest that the observed emission lies along 
the boundary of a conical structure, a situation which has probably 
originated through mass entrainment of dense gas in the galaxy disk along 
the edges of a low density outflow.  The proposers wish to obtain long slit 
observations of this structure.  The goals are: 1} to confirm or reject 
this picture kinematically; 2} investigate how gas is entrained into the 
outflow from the dense ism in the galaxy disk in the inner region of the 
outflow at unprecedented spatial resolution for a Seyfert galaxy {our 
resolution of 1 pc is comparable to or smaller than the expected radius of 
the inner edge of the putative blocking ``torus''}; 3} distinguish between 
collimation of ionization photons or of gaseous outflow as the origin of 
the "ionization cone''; and 4} attempt to measure the mass of the nuclear 
black hole using a long slit spectrum of the disk HII regions.  The 
observations completed with no reported problems.

    1.15 Completed WF/PC-2 8698 (Identification of the Galaxy's Missing Mass)

        The WF/PC-2 was used to observe the nature of dark matter that is 
one of the key astrophysical questions of the day.  The existence of dark 
matter and its dynamical dominance in the outer parts of our Galaxy and 
spiral galaxies with flat rotation curves is well established.  The MACHO 
project has identified ~half of the Milky Way's dark matter with stellar 
objects of ~0.5 M_sun, probably white dwarfs.  But the location of the 
microlensing in the halo is disputed.  Several have detected two candidate 
halo white dwarfs of L/L_sun ~ 10^-5 in the Hubble Deep Field with 25 +/- 5 
mas/year proper motions.  The observations completed with no reported problems.

2.0 FLIGHT OPERATIONS SUMMARY:

    2.1 Guide Star Acquisitions:
       Scheduled Acquisitions: 11
Successful: 11

  Scheduled Re-acquisitions:  7
Successful:  7

    2.2 FHST Updates:
Scheduled: 27
Successful: 26

        Per HSTAR 8089, the roll delay update scheduled for 057/135513Z 
failed due to tracker #1.  The attitude had been drifting for several hours 
due to the acquisition failure detailed in yesterday's report and HSTAR 
8088.  The following full maneuver updates were successful.

    2.3 Operations Notes:

        The first of three target-of-opportunity visits this week (see 1.1 
above) occurred with no reported problems.

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

        The engineering status buffer limits were adjusted at 057/1356Z as 
directed by ROP DF-18A.

        A TTR was written for a required re-transmit at 058/031529Z during 
a NSSC-1 uplink.

        SI C&DH errors were reset at 058/0323Z per ROP NS-5.

3.0 SIGNIFICANT FORTHCOMING EVENTS:

        GSFC Internal Simulation #5 (EVA-4 ) will be conducted today in the 
STOCC area with normal operations continuing from the SIMOR at the STScI.

        Continuation of normal science observations and calibrations.

/CAW