Status Report

Hubble Space Telescope Daily Report #2753 11/20/00

By SpaceRef Editor
November 20, 2000
Filed under ,

HUBBLE SPACE TELESCOPE
 
  DAILY REPORT #2753
 
PERIOD COVERED:  0000Z (UTC) 11/17/00 – 0000Z (UTC) 11/20/00
 
Daily Status Report as of 325/0000Z
 
1.0 OBSERVATIONS SCHEDULED AND ACCOMPLISHED:
 
    1.1 Completed Two Sets of STIS/CCD 8631 (Bright Quasar Close Lensing Search II)
 
        The Space Telescope Imaging Spectrograph (CCD) was used to expand the Cycle 8 second generation HST snapshot survey of bright quasars, optimized to find lenses with component image separations < 1".  The observations completed nominally.
 
    1.2 Completed Four Sets of WF/PC-2 8805 (POMS Test Proposal: WFII Parallel Archive Proposal Continuation)
 
        The WF/PC-2 was used to perform a generic target version of the WFPC2 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.  The proposal completed with no reported problems.
 
    1.3 Completed Five 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.
 
    1.4 Completed Five 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 Two Sets of STIS/CCD 8580 (Pre-Cassini/Huygens Studies of Titan’s Surface, Troposphere and Stratosphere)
 
        The Space Telescope Imaging Spectrograph (CCD) was used to observe Titan, Saturn’s largest satellite.  Titan has an opaque atmosphere in UV and visible wavelengths due to aerosols and methane gas.  This proposal performs a data-dense suite of observations to {a} map the
three-dimensional distribution of methane and aerosols in Titan’s troposphere and stratosphere with the possibility of detecting moving weather patterns, {b} provide a history of the distribution of haze in preparation for Cassini and Huygens observations, and {c} map Titan’s surface albedo with unprecendented spatial resolution and signal/noise.  As described in 2.1 and HSTAR 7972, the acquisition for the second iteration of this proposal defaulted to fine lock backup on one FGS only, possibly affecting the observations in that iteration.  Otherwise, there were no further reported problems.
 
    1.6 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.
 
    1.7 Completed Three Sets of WF/PC-2/STIS/CCD 8641 (Testing the Accelerating Universe)
 
        The WF/PC-2 and the Space Telescope Imaging Spectrograph (CCD) were used to observe Type Ia supernovae which provide evidence for an accelerating universe: an extraordinary result that needs to be rigorously tested.  The observations completed with no reported problems.
 
    1.8 Completed Five Sets of 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.
 
    1.9 Completed Three Sets of 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.
 
    1.10 Completed WF/PC-2 8183 (Morphology of the Most Massive Galaxies in the Early Universe)
 
        The WF/PC-2 was used to make observations of the massive radio galaxy MRC2224-27 in order to study its morphology.  High redshift radio galaxies are fundamentally important probes of galaxy and cluster formation.  The observations were completed as scheduled, and no anomalies were reported.
 
    1.11 Completed Three Sets of STIS/CCD 8841 (Hot Pixel Annealing C9)
 
        The Space Telescope Imaging Spectrograph (CCD) was used to improve the effectiveness of the CCD hot pixel annealing process.  This is assessed by measuring the dark current behavior before and after annealing and by searching for any window contamination effects.  In addition CTE performance is examined by looking for traps in a low signal level flat.  The observations completed with no reported problems.
 
    1.12 Completed Five Sets of WF/PC-2 8826 (Cycle 9 Supplemental Darks pt 1)
 
        The WF/PC-2 was used to perform a T dark calibration program that obtains three dark frames every day in order to provide data for monitoring and characterizing the evolution of hot pixels.  There were no reported anomalies.
 
    1.13 Completed WF/PC-2 8583 (Imaging Snapshots of Asteroids)
 
        The WF/PC-2 was used to obtain images of the fifty largest main belt asteroids that have favorable apparitions during cycle 9.  The images will be searched for companion bodies, as well as mineralogical variegation on the resolved main bodies.  There were no reported problems.
 
    1.14 Completed Two Sets of STIS/CCD/MA1 8107 (What is the Nature of the Cold Medium in Cooling Flow Clusters?)
 
        The Space Telescope Imaging Spectrograph (CCD and MA1) was used to observe X-ray spectra of cooling flow clusters of galaxies in an attempt to discover the presence of large columns of "cold” absorbing material.  The proposal completed with no reported problems.
 
    1.15 Completed STIS/CCD/MA1 8638 (Temperature Scale And Metal Abundances Of Hot Hydrogen-Rich Central Stars Of Planetary Nebulae)
 
        The Space Telescope Imaging Spectrograph (CCD and MA1) was used to perform UV spectroscopy on a sample of hot hydrogen-rich central stars of PNe, covering the hottest phase of post-AGB evolution. The spectra will then be analyzed with fully metal line blanketed NLTE model atmospheres in order to determine T_eff, surface gravity, and chemical composition.  The proposal completed with no reported problems.
 
    1.16 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.
 
    1.17 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.
 
    1.18 Completed WF/PC-2/STIS/CCD 8559 (The Role of Dark Matter in Cluster Formation and Galaxy Evolution)
 
        The WF/PC-2 and the Space Telescope Imaging Spectrograph (CCD) were used to observe the outer regions of massive clusters that represent transitional areas of great cosmological importance where field galaxies encounter the steep potential wells of dark matter and baryonic hot gas.  Little is known about either the dark matter profile at large radii or the morphological properties of infalling galaxies at those redshifts where strong evolution is observed in the cluster cores.  The proposal completed normally, with no reported problems.
 
    1.19 Completed WF/PC-2 8290 (Weather, Moons, and Orbit of the Brown Dwarf Gl 229B)
 
        The WF/PC-2 was used to make observations of the brown dwarf star HD42581 (a.k.a., GI 229B).  Gl 229B is the only unambiguous brown dwarf.  It can be imaged with high astrometric and photometric accuracy only by HST.  The observations were executed as scheduled, and no anomalies were noted.
 
    1.20 Completed WF/PC-2 8815 (Cycle 9 Earth Flats)
 
        The WF/PC-2 was used to monitor flatfield stability.  This proposal obtains sequences of Earth streak flats to construct high quality flat fields for the WF/PC-2 filter set.  These flat fields will allow mapping of the OTA illumination pattern and will be used in conjunction with previous internal and external flats to generate new pipeline superflats.  The proposal completed nominally.
 
    1.21 Completed WF/PC-2 8645 (A Survey of Mid-UV Morphology of Nearby Galaxies: Galaxy Structure and Faint Galaxy)
 
        The WF/PC-2 was used to investigate the relation between star formation and the global physical characteristics of galaxies to interpret the morphologies of distant galaxies in terms of their evolutionary status.  The observations completed nominally.
 
    1.22 Completed Two Sets of 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.
 
    1.23 Completed WF/PC-2 6639 (Star Clusters And The Duration Of Starbursts)
 
        The WF/PC-2 was used to investigate starbursts, which are a fascinating but poorly understood phenomenon that probably plays a key role in galaxy evolution.  Here, we propose to determine one of their most basic properties, namely the duration of the burst.  The proposal completed nominally.
 
    1.24 Completed WF/PC-2 8587 (Stroemgren Photometry of Globular Clusters in M87: Breaking the Age- Metallicity Degeneracy)
 
        The WF/PC-2 was used to further demonstrate that the globular cluster {GC} systems of most, and possibly all, luminous galaxies show bimodal distributions in broadband color and, by implication, age and/or metallicity.  Whatever its origin, this bimodality {which is observed in giant galaxies that span a wide range in Hubble Type and local environment} must hold a fundamental clue to the process of galaxy formation.  The technique of this proposal hinges on the ability of Stroemgren photometry to decouple the effects of age and metallicity for large samples of GCs, and will provide the first strong constraints on the various galaxy formation models.  There were no reported problems.
 
    1.25 Completed WF/PC-2 8604 (Stellar Populations Across the Small Magellanic Cloud (SMC) : History and Structure)
 
        The WF/PC-2 was used to investigate the structure and evolutionary history of the SMC by obtaining a series of 50 three-color snapshots of selected SMC regions.  With this polling of SMC field star properties, we will produce color-magnitude diagrams in the U, V and I bands which will reach V~23.5 in regions too crowded to be observed accurately from the ground.  The observations completed nominally.
 
    1.26 Completed FGS/1R 8728 (The Low-Mass Multiple System GL 831 {Wolf 922}: Definitive Orbit and the Mass-Luminosity Relation)
 
        Fine Guidance Sensor (FGS) 1R was used to observe GL 831 = Wolf that belongs to the select group of about one dozen nearby multiple systems suitable for calibrating the empirical mass-luminosity relation for masses below 0.2 Msun.  This has been observed 13 times with FGS3 through Cycle 7.  However, use of FGS 1R should clarify the location and nature of a fainter third component, possibly of 0.1 Msun, detected in two observations with the less capable FGS3.  The observations completed nominally.
 
    1.27 Completed Four Sets of WF/PC-2 8699 (The Origin of Short-Period Comets)
 
        The WF/PC-2 was used to detect and characterize cometary nuclei in order to determine the basic physical properties of a large fraction of the population of short-period comets.  By acquiring statistically significant data, we can study the origin of this family of comets and test the hypothesis that they are collisional fragments from the Kuiper Belt Objects.  The observations completed with no reported problems.
 
    1.28 STIS/MA1/MA2 8843 (Cycle 9 MAMA Dark Measurements)
 
        The Space Telescope Imaging Spectrograph (MA1 and MA2) was used to perform the routine monitoring of the MAMA detector dark noise.  The proposal completed nominally.
 
    1.29 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.
 
2.0 FLIGHT OPERATIONS SUMMARY:
 
    2.1 Guide Star Acquisitions:
      Scheduled Acquisitions: 33
                Successful: 33
 
        As described in HSTAR 7972, the acquisition at 324/203158Z defaulted to fine lock backup on FGS-2 only when the scan step limit was exceeded for FGS-1.  The proposal detailed in 1.5 may have been affected.     Scheduled Re-acquisitions: 15
                  Successful: 15
 
    2.2 FHST Updates:
                  Scheduled: 70
                  Successful: 70
 
    2.3 Operations Notes:
 
        HST operations continue to be performed from the GSFC STOCC.  The team is using CCS "B" string" as prime with CCS "C" string as backup.
 
        Using ROP SR-1A, correctable SSR EDAC errors were cleared on nine occasions.
 
        The SI C&DH error counter was reset twice, per ROP NS-5.
 
        The engineering status buffer limits were adjusted twice, per ROP DF-18A.
 
        SSA transmitter #1 was turned on at 322/1228Z and turned off at 322/1252Z, as directed by ROP IC-2.
 
      A TTR was written for a required re-transmission during a NSSC-1 load at 322/2004Z.  Another TTR was written for a similar event at 324/0404Z.
 
        SSA transmitter #2 was turned on at 325/0553Z and turned off at 325/0654Z, per ROP IC-2.
 
3.0 SIGNIFICANT FORTHCOMING EVENTS:
 
        Continuation of normal science observations and calibrations.

SpaceRef staff editor.