Hubble Space Telescope Daily Report #2683 08/10/00
HUBBLE SPACE TELESCOPE
DAILY REPORT #2683
PERIOD COVERED: 0000Z (UTC) 08/09/00 – 0000Z (UTC) 08/10/00
Daily Status Report as of 223/0000Z
1.0 OBSERVATIONS SCHEDULED AND ACCOMPLISHED:
1.1 Completed WF/PC-2/STIS/CCD/MA2 8047 (Observations of Globular Cluster Stars)
The WF/PC-2 and the Space Telescope Imaging Spectrograph (CCD and MA2) were to be used to observe the star NGC5139 in the globular cluster which has been found to have large helium abundance {Y = 0.67}. As described in yesterday’s report and HSTAR 7783, the acquisition and re-acquisition for this proposal failed. All planned observations were lost when the take data flag remained down.
1.2 Completed STIS/CCD 8439 (Bias Monitor-Part 2 C8)
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 with no reported problems.
1.3 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.
1.4 Completed WF/PC-2/STIS/CCD 8675 (The Massive Star Content of NGC 6822)
The WF/PC-2 and the Space Telescope Imaging Spectrograph (CCD) were used to characterize the young, coeval stellar population discovered with WFPC2 multiband imaging in a NGC6822 star forming region, with follow-up spectroscopy of the massive star candidates. The proposal completed with no reported problems.
1.5 Completed STIS/CCD 8114 (Fundamental Problems in Plasma Astrophysics)
The Space Telescope Imaging Spectrograph (CCD) was used to observe NGC 7009 which has become the standard-bearer for a growing body of work that finds nebular abundances derived from recombination lines are up to factors of 5–15 larger than those obtained from the optical/UV collisionally excited lines. These can be forced into agreement at the higher value if large unexplained temperature fluctuations {t^2} exist. STIS long-slit observations will allow us to study the line-of-sight t^2 in addition to plane-of-the-sky variations, within the slit areas, thereby creating 3-dimensional t^2 information. The proposal completed nominally.
1.6 Completed 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.
1.7 Completed WF/PC -2 8177 (Investigating Type Ia Supernovae and an Accelerating Universe)
The WF/PC-2 was used to obtain rest frame U and B photometry for four z~ 0.85 Supernova (SN) Ia. These observations will be coupled to ground-based rest frame V photometry and spectra. These data, combined with previous samples, will extend the D_L vs. z diagram for SN Ia to z~0.85, and allow us to discriminate the redshift dependence of supernova magnitudes in an accelerating Universe from that expected to result from systematic effects such as age of the stellar population, chemical evolution, a drift in the properties of dust, and weak gravitational lensing. The proposal completed with no reported problems.
1.8 Completed Two Sets of STIS/CCD 8808 (POMS Test Proposal: STIS Non-Scripted Parallel Proposal Continuation III)
The Space Telescope Imaging Spectrograph (CCD) was used to make non-scripted, parallel observations as part of a POMS test proposal. The observations completed with no anomalous activity.
1.9 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.
1.10 Completed STIS/CCD/MA2 8266 (Coherence Length of Lyman-Alpha Absorbers at z ~ 1)
The Space Telescope Imaging Spectrograph (CCD and MA2) was used to measure the coherence length of Lyman-Alpha absorbers in the redshift range 0.5 < z < 1.1, using a new pair of quasars with a separation of 130 arcseconds. For quasars with this brightness {R = 18.1}, redshift and separation are very rare. Coincident absorbers along the line-of-sight to quasar pairs can reveal the geometry of the diffuse but highly ionized gas that makes up the Lyman-Alpha forest; this gas represents the majority of the baryons and it traces the underlying dark matter distribution. The observations completed with no reported anomalies.
1.11 Completed WF/PC-2 8822 (Decontaminations and Associated Observations Pt. 1/4)
The Wf/PC-2 was used for the monthly decons. Also included are 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.
2.0 FLIGHT OPERATIONS SUMMARY:
2.1 Guide Star Acquisitions:
Scheduled Acquisitions: 5
Successful: 5
Scheduled Re-acquisitions: 10
Successful: 10
2.2 FHST Updates:
Scheduled: 13
Successful: 13
2.3 Operations Notes:
Using ROP SR-1A, the SSR EDAC error counter was cleared twice.
Per ROP IC-2, SSA-2 was turned on and off at 222/1358Z.
Operations transferred from the Science Institute to the GSFC MOR at 222/1743Z. CCS string "A" became the prime operations string at 222/1947Z. Then, at 223/0727Z, CCS string "G" was configured as the prime operations string, and operations transferred to the Science Institute at 223/0921Z.
3.0 SIGNIFICANT FORTHCOMING EVENTS:
The return to the target of opportunity Comet Linear proposal on days 224 and 225.
Continuation of normal science observations and calibrations.