Status Report

Hubble Space Telescope Daily Report #2788 01/17/01

By SpaceRef Editor
January 17, 2001
Filed under ,

PERIOD COVERED:  0000Z (UTC) 01/16/01 – 0000Z (UTC) 01/17/01
Daily Status Report as of 017/0000Z
    1.1 Completed WF/PC-2 8706 (Phoenix: "Halo/Disk” Structures In Dwarf Galaxies)
        The WF/PC-2 was used to perform hierarchical clustering scenarios for galaxy formation that predict that dwarf galaxies are the first to be formed and that they are building blocks of larger galaxies.  In this case, the spatial structure and the stellar age and metallicity distribution of the Phoenix dwarf galaxy are measured to give support or reject such scenarios.  The proposal completed with no anomalous activity.
    1.2 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.  The proposal completed nominally.
    1.3 Completed WF/PC-2 8601 (A Snapshot Survey of Probable Nearby Galaxies)
        The WF/PC-2 was used to continue the very successful snapshot survey in order to use the high spatial resolution of HST to determine whether selected galaxies are nearby on the basis of resolution into stars, and the magnitudes and colors of the brightest stars.  There were no reported problems.
    1.4 Completed STIS/CCD 8663 (Survey of SMC Planetary Nebulae: Nebular and Stellar Evolution in a Low- Metallicity Environment)
        The Space Telescope Imaging Spectrograph (CCD) was used to survey of SMC planetary nebulae {PNe} in order to study the co-evolution of the nebulae and their central stars, in an environment that is chemically very metal poor.  We will obtain STIS imaging and medium-resolution slitless spectroscopy that will yield line fluxes and nebular morphologies in important emission lines, plus magnitudes of the central stars.  From these data we will gather a harvest of information: the nebular size, morphology, ionization structure, density, and mass; and the central star temperature, luminosity, and mass.  The proposal completed with no reported anomalies.
    1.5 Completed STIS/CCD/MA1 8287 (A Search For Transparent Lines of Sight With Intergalactic He-II Absorption Towards 26 Bright z > 2.9 Quasars)
        The Space Telescope Imaging Spectrograph (CCD and MA1) was to be used to make He-II absorption line observations of quasar HS1106-035.  As described in 2.1 and HSTAR 8045, the acquisition for this proposal failed, the take data flag remained down, and all observations were lost.
    1.6 Completed STIS/CCD 8837 (CCD Dark Monitor-Part 1)
        The Space Telescope Imaging Spectrograph (CCD) was to be used to monitor the darks.  As described in 2.1 and HSTAR 8045, the acquisition for this proposal failed, the take data flag remained down, and all observations were lost.
    1.7 Completed WF/PC-2 8816 (Cycle 9 UV Earthflats)
        The WF/PC-2 was to be 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.  As described in 2.1 and HSTAR 8045, the acquisition for this proposal failed, the take data flag remained down, and all observations were lost.
    1.8 Completed STIS/CCD 8838 (Bias Monitor – Part 1)
        The Space Telescope Imaging Spectrograph (CCD) was used to monitor the bias in the 1×1, 1×2, 2×1, and 2×2 bin settings at gain=1, and 1×1 at gain = 4, to build up high-S/N superbiases and track the evolution of hot columns.  The proposal completed nominally.
    1.9 Completed WF/PC-2 8577 (Ozone, Condensates, and Dust in the Martian Atmosphere)
        The WF/PC-2 was used to study the spatial and seasonal variations in ozone, condensates, and dust in the Martian atmosphere.  The data obtained promise to be critical in addressing recent breakthroughs in understanding the basic radiative, transport, and microphysical processes that provide for both long-term and short-term balance within the global Mars climate system.  There were no reported problems.
    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 8720 (Masses and Multiplicity of Nearby Free- floating Methane and L Dwarfs)
        The WF/PC-2 was used to observe 50 very-low-mass objects in the solar neighborhood with spectral types of L0 and later {including several dwarfs with Methane absorption bands in their atmospheres}.  These objects will be observed in two filter bands with the aim to identify close companions, measure their colors, and to obtain first epoch data of the newly discovered binaries.  The observations completed nominally.
    1.12 Completed WF/PC-2 8597 (The Fueling of Active Nuclei: Why are Active Galaxies Active?)
        The WF/PC-2 was used to investigate the accretion onto massive black holes that are believed to be the energy source for AGN.  However, evidence for black holes in quiescent galaxies has also been reported.  Why are these galaxies inactive?  One possibility is that active galaxies are better at providing fuel to the nuclear region than quiescent
galaxies.  Other possible fueling mechanisms such as “bars-within-bars” or nuclear spirals cannot be investigated from the ground because they are relatively small features in the ISM.  The observations were completed as planned.
    1.13 Completed WF/PC-2/STIS/CCD/MA2 8568 (A Seminal Spectroscopic and Imagery Investigation of the Brightest Wolf-Rayet Shell Nebula: NGC 6888)
        The WF/PC-2 (for imagery) and the Space Telescope Imaging Spectrograph (CCD for UV-optical-NIR spectroscopy of several regions in the brightest Wolf-Rayet Shell along with MA2) were used to observe Nebula {WRSN}, NGC 6888.  The physical conditions in the wind-driven and/or stellar ejected plasma {temperature, density, ionization, and composition} of WRSN, which are dominated by strong stellar winds from hot massive stars in an advanced state of evolution, often involve emission from both shock-ionized and photoionized gas in close proximity.  These new observations will comprise the first combined spectroscopy and imagery of a WRSN at a resolution sufficient to separate and individually analyze these two emission regions.  The proposal completed nominally with no reported problems.
    1.14 Completed 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.
    2.1 Guide Star Acquisitions:
      Scheduled Acquisitions:  9
Successful:  8
        The acquisition scheduled for 016/140941Z failed to RGA control when the scan step limit was exceeded on FGS-2.  A subsequent map showed small errors.  The following guide star acquisition was
successful.  Proposals detailed in 1.5, 1.6, and 1.7 were affected.   Scheduled Re-acquisitions:  8
Successful:  8
    2.2 FHST Updates:
Scheduled: 19
Successful: 19
    2.3 Operations Notes:
        Using ROP SR-1A, the SSR EDAC error counter was cleared four times.
        As directed by operations requests, additional data for the Gyro #6 Power Cycle On-orbit Test was obtained in PN and HN formats on three occasions.
        The Gyro #6 Power Cycle On-orbit Test was terminated at approximately 016/1324Z with the removal of the flight software patch.  The subsequent type 2 slew at 016/1346Z showed that Gyro #6 had properly transitioned to High Mode with the other gyros that were in the control loop.  Due to significantly longer than expected time for Gyro #6 to recover after a slew, when forced to remain in Low Mode, the Power Cycle Test has been postponed until further notice.
        SSA transmitter #2 was turned on at 016/1409Z and turned off at 016/1437Z per ROP IC-2.
        ROP NS-12 was used at 016/1450Z to reset the STIS flight software error counter and ROP NS-5 was used at 016/1454Z to reset NSSC-1 errors, following the acquisition failure described in 2.1.
        The NSSC-1 status buffer was dumped at 016/1823Z per ROP NS-5.
        Continuation of normal science observations and calibrations.

SpaceRef staff editor.