Status Report

Hubble Space Telescope Daily Report #2796 01/29/01

By SpaceRef Editor
January 29, 2001
Filed under ,

PERIOD COVERED:  0000Z (UTC) 01/26/01 – 0000Z (UTC) 01/29/01
Daily Status Report as of 029/0000Z
    1.1 Completed Four Sets of 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.
    1.2 Completed Fifteen 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 loss-of-lock described in 2.1 and HSTAR 8063 occurred during the final iteration of this proposal.  Otherwise, the proposal completed nominally.
    1.3 Completed STIS/CCD 8603 (Secular Changes In The Temperatures And Radii Of Extreme Helium Stars)
        The Space Telescope Imaging Spectrograph (CCD) was used to make observations of 15 extreme helium stars (EHEs_ which, together with IUE data, will give a 20-year baseline of ultraviolet spectrophotometry.  EHEs are luminous stellar remnants evolving rapidly to become white
dwarfs.  They represent an important stage in the evolution of at least some low-mass stars, and are closely related to the R Coronae Borealis variables.  Models do not agree about their origin, nor about what fraction of normal stars pass through this phase, in which the stars have been completely stripped of their outer layers.  The models do predict that EHEs are contracting and provide rate predictions and evolutionary
lifetimes.  The observations completed with no reported problems.
    1.4 Completed Six 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 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.
    1.6 Completed STIS/CCD/MA1 8108 (Search for the Origin of Supersonic Turbulence Observed in the Upper Equatorial Atmosphere of Jupiter)
        The Space Telescope Imaging Spectrograph (CCD and MA1) was used to observe Jupiter, which like the Sun, sustains a coronal region at the top of its atmosphere.  H-Ly-alpha spectra measured by GHRS in the Jovian Ly-alpha bulge region, evidenced a non thermal line broadening, implying supersonic atomic motions and variability on a time scale of about one minute.  The re-acquisition failure described in 2.1 and HSTAR 8060 occurred during this proposal, affecting six of the
observations.  Otherwise, the observations completed with no further reported problems.
    1.7 Completed WF/PC-2 8110 (Supernova Remnants in a Cloudy Interstellar Medium)
        The WF/PC-2 was used to observe small cloudlets in the interstellar medium {ISM} that may have a marked effect on the physical structure and evolution of supernova remnants {SNRs}.  These WFPC2 images can be combined with complementary observations in other wavelength regimes to identify cloudlets inside remnants, trace SNR shock fronts, determine the physical parameters of interior cloudlets and compare them to those of the hot interior, and investigate the evaporation of shocked cloudlets into the hot cavities of the SNRs.  There were no reported problems.
    1.8 Completed Seven 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 WF/PC-2 8599 (A Census of Nuclear Star Clusters in Late-Type Spiral Galaxies)
        The WF/PC-2 was used to conduct an I-band snapshot survey of a well-defined sample of nearby, face-on spiral galaxies of type Scd or later.  The proposal completed nominally.
    1.10 Completed Six 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.
    1.11 Completed Two Sets of 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.
    1.12 Completed Two Sets of WF/PC-2/STIS/CCD 8191 (The Faintest Radio Galaxies: Interacting Starbursts at z<1)
        Deep WF/PC-2 imaging and Space Telescope Imaging Spectrograph (CCD) slitless spectroscopy of two of our ultra-deep VLA fields were
performed.  There were no reported problems.
    1.13 Completed STIS/CCD/MA1 8590 (UV Imaging and Spectroscopy of Luminous Blue Compact Galaxies from z=0 to z=1)
        The Space Telescope Imaging Spectrograph (CCD and MA1) was used to observe two well-defined samples of low-mass starburst galaxies, one in the local universe {z<0.1} and another at intermediate redshifts {0.2 < z < 0.7}.  Both samples show optical sizes, morphologies, emission line widths, and luminosities comparable to those of LBGs at z=3, and are therefore probably the best local analogs and testbeds for further study of LBGs.  Our main goals are to: {1} explore the morphologies, surface brightness distributions, and half-light radii of nearby starforming galaxies in the FUV, near Ly-alpha; {2} search for systematic differences among UV, optical, and near-IR morphologies and structural parameters; {3} investigate the intrinsic emission and absorption spectra near Ly-alpha of starbursting dwarf galaxies, with special attention to Ly- alpha profiles and interstellar and stellar photospheric absorption from Si II, O I, C II, Si IV, and C IV; {4} measure their FUV-optical colors and dust extinction properties; and {5} test the hypothesis that low-mass starbursts are the local counterparts of LBGs.  The observation completed normally.
    1.14 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.
    1.15 Completed WF/PC 8233 (UV Imaging of Optical Jets: A New Window on the Physics of Jets)
        The WF/PC-2 was used to observe extragalactic radio jets which are highly collimated beams of high energy particles and magnetic fields issuing forth at relativistic speeds from sub-parsec scale regions, extending hundreds of kpc through interstellar and intergalactic space.  They are unique in their scope, power, and size. The jets affect their host galaxies and environments, through kinetic energy output and through deposition of cosmic rays and magnetic fields into interstellar and intergalactic space.  Despite years of study, fundamental jet parameters such as the magnetic field strength, particle density, jet configuration, bulk Lorentz factor, and the nature of particle acceleration in the flow remain unknown.  The observations completed with no anomalous activity.
    1.16 Completed Two 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.
    1.17 Completed WF/PC-2 8823 (Decontaminations and Associated Observations Pt. 2/4)
        The WF/PC-2 was used for the monthly WFPC2 decons.  Also included were instrument monitors tied to decons: photometric stability check, focus monitor, pre- and post-decon internals {bias, intflats, kspots, & darks}, UV throughput check, VISFLAT sweep, and internal UV flat check.  There were no reported problems.
    1.18 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.
    1.19 Completed WF/PC-2 8682 (A Snapshot Study of 0bservational Cosmology)
        The WF/PC-2 was used to examine the observational constraints on the cosmic star formation history that is currently among the most active fields in observational cosmology.  The most widely used tracer of the co-moving volume-averaged star formation rate {SFR} is the UV luminosity density, which early results found to peak at z~1- 2.  The apparent identification of the primary epoch of metal production and star formation in the Universe led to intense theoretical and observational
interest.  Nevertheless, and remarkably for such a fundamental observation, little is known about the history of star formation in the Universe beyond its global average.  The loss-of-lock described in 2.1 and HSTAR 8063 occurred during this proposal.  Otherwise, there were no other reported anomalies.
    1.20 Completed STIS/CCD/MA1 8117 (Saturn’s Far UV Aurora and Polar Hazes)
        The Space Telescope Imaging Spectrograph (CCD and MA1) was used to carry out a coordinated program of STIS imaging and spectroscopy in the FUV and NUV during one full rotation of the planet in order to capture a complete picture of the south auroral emission region on Saturn.  FUV imaging and chapman-profile modeling is our lever to characterize emissions from above the homopause, while FUV and NUV spectroscopy and radiative transfer modeling will describe the atmospheric phenomena driven by particle radiation that penetrates below the homopause.  The proposal completed with no reported problems.
    1.21 Completed STIS/MA1 8476 (Nearby Starbursts And The Evolutionary Link To AGNs)
        The Space Telescope Imaging Spectrograph (MA1) was used to explore the evolutionary link between starburst galaxies and active glactic nuclei.  Starburst activity in nearby galaxies and extended emission line regions are probed.  The UV spectrum of starbursts will be modeled using spectral synthesis techniques and AGN emission line ratios will be used to explore photoionization and shock ionization scenarios.  No problems were reported.
    1.22 Completed STIS/CCD 8607 (Completing the Local AGN Inventory: The AGN Content of Composite Nuclei)
        The Space Telescope Imaging Spectrograph (CCD) was used to increase the knowledge of the local space density of AGNs which is of fundamental importance to a number of astrophysical problems.  A significant fraction of nearby galaxies have nuclei whose spectra are intermediate between those of LINERs and nuclear starbursts.  These “transition objects” may be composite systems that contain both a central AGN and circumnuclear star formation.  We will test this hypothesis by obtaining spatially-resolved optical spectra of a well-defined sample of 15 nearby transition nuclei selected from the extensive ground-based survey of Ho, Filippenko, and Sargent.  The observations completed with no reported problems.
    1.23 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.
    1.24 Completed STIS/CCD 8884 (POMS Test Proposal: STIS Non-Scripted Parallel Proposal Continuation)
        The Space Telescope Imaging Spectrograph (CCD) was used to take parallel images of random areas of the sky.  The proposal completed nominally.
    2.1 Guide Star Acquisitions:
      Scheduled Acquisitions: 20
Successful: 20
        A loss-of-lock, following a successful acquisition at 028/071006Z, occurred at 028/071649Z.  Lock was restored via new #44 commands.  HSTAR 8063 was written.  Proposals detailed in 1.2 and 1.19 were affected.   Scheduled Re-acquisitions: 23
Successful: 22
        The re-acquisition scheduled for 026/130148Z failed to RGA control when the scan step limit was exceeded on FGS-3.  HSTAR 8060 was written.  The proposal described in 1.6 was at least partially affected.
    2.2 FHST Updates:
Scheduled: 56
Successful: 56
    2.3 Operations Notes:
        Using ROP SR-1A, the SSR EDAC error counter was cleared seven times.
        The engineering status buffer limits were adjusted twice per ROP DF-18A.
        Three TTRs were written for required re-transmits during loads: twice for 486 loads and one for an NSSC-1 load.
        A routine RF Transfer Switch 1 and 2 scrub occurred at 026/1348Z during a TDRS-W pass.
        The STIS MCE-1 reset at 027/093120Z while the low voltage was on and while inside an SAA boundary.  The STIS flight software error counter was reset at 027/0934Z as directed by ROP NS-12.  MAMA-1 was recovered at 027/1432Z via SMS commanding while transitioning to high voltage.
        Per ROP NS-5, SI C&DH errors were reset at 028/1120Z.
        Continuation of normal science observations and calibrations.

SpaceRef staff editor.