Hubble Space Telescope Daily Report #2694 08/25/00
HUBBLE SPACE TELESCOPE
DAILY REPORT #2694
PERIOD COVERED: 0000Z (UTC) 08/24/00 – 0000Z (UTC) 08/25/00
Daily Status Report as of 238/0000Z
1.0 OBSERVATIONS SCHEDULED AND ACCOMPLISHED:
1.1 Completed STIS/CCD 8640 (A Public STIS Survey of the Host Galaxies of Gamma-Ray Bursts)
The Space Telescope Imaging Spectrograph (CCD) was used to obtain high-resolution images of the fields containing gamma-ray burst with well-localized coordinates; i.e. the burst has been localized to within approximately one arcsecond. The goal of this survey is to obtain a uniform sample of images of the host galaxies of these bursts. There were no reported problems.
1.2 Completed Six 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. The proposal completed with no reported problems.
1.3 Completed Three 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.
1.4 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
1.5 Completed Two Sets of STIS/CCD 8437 (Dark Monitor-Part 2 C8)
The Space Telescope Imaging Spectrograph (CCD) was used to monitor the darks. The proposal completed nominally.
1.6 Completed WF/PC-2 8655 (Geometric Distances of Globular Clusters {GO part})
The WF/PC-2 was used to establish a globular-cluster distance scale of unprecedented accuracy and reliability, with far- reaching impact on the distance and time scales of cosmology. Our method is to compare internal dispersions of proper motion with ground-based determinations of the dispersion of radial velocities. The prospect is a geometrically based distance scale with an accuracy of better than 2 ability to make such measurements, and we are progressing with the conversion of them to a distance for the cluster. The observations completed with no reported problems.
1.7 Completed Three Sets of WF/PC-2/STIS/CCD 8414 (STIS Sparse Field CTE test {Cycle 8))
Both the WF/PC-2 and the Space Telescope Imaging Spectrograph (CCD) were used to conduct CTE measurements using the "sparse field test", along both the serial and parallel axes. This program needs special commanding to provide {a} off-center MSM positionings of some slits, and {b} the ability to read out with any amplifier {A, B, C, or D}. All exposures are internals. The observations were completed as planned, and no anomalies were reported.
1.8 Completed STIS/CCD/MA2 8621 (The Galactic Abundance Gradients of Boron and Iron)
The Space Telescope Imaging Spectrograph (CCD and MA2) was used to provide the first measurement of the Galactic abundance gradients for Boron and Iron. Boron abundances were obtained for 5 B-type stars {with Galactocentric distances between 4-15 kpc} from the BIII 2066 Angstrom line. Optical spectroscopy of these {and other B-type} stars has yielded abundance gradients of -0.07 dex/kpc for N & the Alpha-elements {O, Mg, Si}. Determination of Boron abundances require UV spectra. The proposal completed nominally.
1.9 Completed Two Sets of STIS/CCD/MA1 8305 (Two Post-Common-Envelope Binaries in the Hyades Cluster)
The Space Telescope Imaging Spectrograph (CCD and MA1) was used to observe V471 Tau and HZ 9, two detached binaries that are members of the Hyades cluster and consist of hot white dwarfs with main-sequence K-M companions. They have emerged from common- envelope interactions which drastically reduced their initially wide separations. For V471 Tau we used STIS to confirm and further explore the host of fascinating phenomena that we have found using GHRS in a very limited spectral range near
Lyman-Alpha. We also used STIS to obtain the first high-resolution UV spectra of HZ 9, to see to what extent the above phenomena occur in a non- magnetic system which is otherwise remarkably similar to V471 Tau, and to determine accurate component masses. The observations completed with no reported problems.
1.10 Completed STIS/MA1 8426 (Cycle 8 MAMA Dark Measurements)
The Space Telescope Imaging Spectrograph (MA1) was used to make a routine Cycle-8 MAMA dark noise calibration measurement. This proposal will provide the primary means of checking on the health of the MAMA detectors. This is done through frequent monitoring of the background count rate. The observations were completed as planned, and no problems were reported.
1.11 Completed STIS/CCD/MA1/MA2 8206 (The Structure of the Accretion Flow on Pre-Main-Sequence Stars)
The Space Telescope Imaging Spectrograph (CCD, MA1 and MA2) was used to test an essential prediction of the magnetospheric accretion model for T Tauri stars. Echelle spectra were be used to search for the relatively narrow high-temperature emission lines that must result from the magnetospheric accretion shock, but are not expected in the previous, alternative boundary layer model. The observations were completed with no reported problems.
2.0 FLIGHT OPERATIONS SUMMARY:
2.1 Guide Star Acquisitions:
Scheduled Acquisitions: 11
Successful: 10
According to HSTAR 7819, the acquisition scheduled for 238/061532Z when the search radius limit was exceeded. The full maneuver FHST update at 238/060844Z had indicated large attitude errors. An attitude reference update was performed at 238/074627Z per COP 3.6B. The following re-acquisition was successful. Three proposals , occurring during the period of the next report, were affected: STIS 8640, WF/PC-2 8059, and WF/PC-2 8816.
Scheduled Re-acquisitions: 7
Successful: 7
2.2 FHST Updates:
Scheduled: 20
Successful: 20
2.3 Operations Notes:
Operations activities returned to the GSFC STOCC area for the grave shift, after performing duties from the Science Institute.
Using ROP SR-1A, the SSR EDAC error counter was cleared three times.
A TTR was written when GCMRs cold not be sent for TDRSS-E events starting at 237/154831Z and 237/173805Z, and for TDRSS-W events starting at 237/165835Z and 237/172547Z. These were caused by CCS ground system problems (see HSTAR 7814).
The 486 engineering status buffer limits were updatred at 238/0628Z per ROP DF-18A.
3.0 SIGNIFICANT FORTHCOMING EVENTS:
Continuation of normal science observations and calibrations.
