HUBBLE SPACE TELESCOPE DAILY REPORT #2326 PERIOD COVERED: 0000Z (UTC) 03/10/99 - 0000Z (UTC) 03/11/99 Daily Status Report as of 070/0000Z 1.0 ACTIVITIES SCHEDULED AND ACCOMPLISHED: 1.1 Completed Two Sets of WF/PC-2 7431 (Snapshot Survey of Microlensed Source Stars) The WF/PC-2 was used to make snapshot survey images of microlensed source star MACHO-134. Gravitational microlensing surveys have revealed an excess of lensing events over theoretical predictions toward both the Large Magellanic Cloud and the Galactic Bulge. The observations were completed as planned, and no anomalies were reported. 1.2 Completed Two Sets of STIS/CCD 7948 (CCD Dark and Bias Monitor -- Cont. to Dec. 98) The Space Telescope Imaging Spectrograph (CCD) was used to measure CCD dark current and bias rates for the two supported amplifier settings {GAIN=1 and GAIN=4} in order to gather data for making superdarks and superbiases. The data will be used to track the growth of hot pixels on the CCD in general and within the various target acquisition apertures specifically. The observations were executed as scheduled, and no anomalies were noted. 1.3 Completed Three Sets of WF/PC-2 7713 (WF/P-2 Cycle 7 Supplemental Darks pt3/3) The WF/PC-2 was used to make supplemental dark calibration images. This dark calibration program obtains three dark frames every day to provide data for monitoring and characterizing the evolution of hot pixels. The observations were completed as planned, and no anomalies were noted. 1.4 Completed WF/PC-2 7343 (Photometric Survey of Galaxies lying Behind Gravitational Lens Cluster) The WF/PC-2 was used to make an extensive photometric survey of the galaxies lying behind the exceptional gravitational lens cluster A2218. The distortion of these images has been mapped from the ground, and shows one of the strongest signals to date, but the signal to noise is still limited. Using WFPC2 images we show that with two orbits on each of 22 fields covering the cluster we will obtain approximately 10000 galaxies over a region extending to 0.9 Mpc/h from the cluster center. The observations were completed with no reported problems. 1.5 Completed Three Sets of STIS/CCD 8091 (POMS Test Proposal: STIS Non-Scripted Parallel Proposal Continuation) The Space Telescope Imaging Spectrograph (CCD) was used to make high galactic latitude, non-scripted, parallel observations. The observations were completed as planned, and no anomalies were noted. 1.6 Completed STIS/CCD 8393 (POMS Test Proposal: STIS Non-Scripted Parallel Proposal Continuation IV) The Space Telescope Imaging Spectrograph (CCD) was used to make POMS, non-scripted, low galactic latitude observations made in parallel with the prime science observations. The observations were executed as scheduled, and no anomalies were noted. 1.7 Completed WF/PC-2 7341 (Absolute Proper Motions of Nearby Dwarf Spheroidal Galaxies) The WF/PC-2 was used to measure precise absolute proper motions for four dwarf spheroidal satellites of the Milky Way using spectroscopically-confirmed background QSOs to define a zero-velocity reference frame. The observation completed as planned with no reported anomalies. 1.8 Completed WF/PC-2 6967 (Blue Continuum Snapshots of 3CR Radio - Continued Galaxies) The WF/PC-2 was used to make observations of the radio galaxy 3C46.0. Radio galaxies are an important class of extragalactic objects: they represent one of the most energetic astrophysical phenomena and they may be used as probes of their environments. They are unique probes of the early Universe. The observations were completed as planned, and no problems were reported. 1.9 Completed WF/PC-2 6357 (The Nuclear Morphology of Elliptical Galaxies) The WF/PC-2 was used to make images of the early type, large, elliptical galaxy IC-875 (taken from a list of 150 galaxies) in order to study its nuclear morphology. This survey will complement Illingworth's snapshot study of later Hubble types. The observations were completed as scheduled, and no anomalies were reported. 1.10 Completed STIS/CCD 7350 (Testing the Supermassive Black Hole Paradigm in Nearby Radio-Quiet AGNs) The Space Telescope Imaging Spectrograph (CCD) was used to make observations of the radio-quiet active galactic nuclei NGC3998. Obtaining a large sample of central engine mass determinations is a crucial first step toward understanding the physics of AGN central engines, including the puzzling difference between radio-loud and radio-quiet AGNs. A wavelength calibration observation was also taken. The observations were completed as planned, and no anomalies were reported. 1.11 Completed Two Sets of WF/PC-2 8090 (POMS Test Proposal: WF-II Parallel Archive Proposal Continuation) The WF/PC-2 was used in the parallel mode to make some low galactic latitude archive observations. The program will be used to take parallel images of random areas of the sky. The observations were executed as scheduled, and no anomalies were noted. 1.12 Completed WF/PC-2 8061 (POMS Test Proposal: WF-II Backup Parallel Archive Proposal) This is a POMS test proposal designed to simulate scientific plans. The proposal was executed as planned, and no anomalies were reported. 2.0 FLIGHT OPERATIONS SUMMARY 2.1 Guide Star Acquisitions: Scheduled Acquisitions : 3 Successful : 3 Scheduled Reacquisitions : 12 Successful : 12 2.2 FHST Updates: Scheduled : 5 Successful : 5 2.3 Operations Notes: Using ROP SR-1, the SSR EDAC error counter was cleared once. A TTR was written for an unrecoverable loss of 3-minutes, 18-seconds of 32K data beginning at 069/180548Z due to WSGT equipment problems. The Gyro-3 rate bias trend data shows a decrease in the least squares linear fit slope since that last report. The slope for this seven-day interval is 1.88 arcseconds/hour/day (was 2.43). This slope meets the 10.8 arcseconds/hour/day desire for re-installation; however, PCS engineers feel this slope is not indicative of a trend since it is dominated by a step shift bias. 3.0 SIGNIFICANT FORTHCOMING EVENTS: Continuation of normal science observations and calibrations. /DMH