HUBBLE SPACE TELESCOPE DAILY REPORT #2325 PERIOD COVERED: 0000Z (UTC) 03/09/99 - 0000Z (UTC) 03/10/99 Daily Status Report as of 069/0000Z 1.0 ACTIVITIES SCHEDULED AND ACCOMPLISHED: 1.1 Completed Two 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. 1.2 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 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. 1.4 Completed Two 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. 1.5 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. 1.6 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 MGC8-27-18 (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. 1.7 Completed STIS/CCD/MA1 7345 (Origin and Physical Conditions in the Local Lyman-Alpha Forest) The Space Telescope Imaging Spectrograph (CCD and MA1) was used to make observations of ABELL2218 in order to study the origin and physical conditions in the local Lyman-Alpha forest. A wavelength calibration image was also taken. The observations were executed as scheduled, and no anomalies were noted. 1.8 Completed 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. 1.9 Completed STIS/MA2 7950 (Cycle 7 MAMA Dark Measurements) The Space Telescope Imaging Spectrograph (MA2) was used to make a dark calibration image. This is to establish if the detectors are performing nominally, that no internal movement of the MCP has taken place, and establish dark level in orbit for a given operating temperature. These darks will be used in later image reduction and also trended over instrument life time as indicators of detector degradation or damage. The observations were completed as planned, and no problems were reported. 1.10 Completed STIS/CCD/MA2 7402 (Chromospheric Activity in Old Stars: Halo Subdwarfs' Variability) The Space Telescope Imaging Spectrograph (CCD and MA2) was used to make observations of the old sub-dwarf star HD114762 in order to study its chromospheric activity. All normal stars cool enough to have convection zones share a common minimum level of chromospheric activity which decreases with advancing spectral type; most show higher emission levels which vary with time. A wavelength calibration observation was also taken. The observations were executed as scheduled, and no anomalies were noted. 1.11 Completed STIS/CCD 7615 (Determination of the Mass Function of a Globular Cluster Through Gravitational Microlensing) The Space Telescope Imaging Spectrograph (CCD) was used to make gravitational microlensing observations of the large globular cluster NGC6656 located in Sagittarius in order to study its mass function. Gravitational microlensing offers a unique and direct method of determining the masses of stars and other compact objects down to planetary masses. A bias and dark calibration observations were also taken. The observations were completed as planned, and no problems were reported. 2.0 FLIGHT OPERATIONS SUMMARY 2.1 Guide Star Acquisitions: Scheduled Acquisitions : 8 Successful : 8 Scheduled Reacquisitions : 9 Successful : 9 2.2 FHST Updates: Scheduled : 17 Successful : 15 Per HSTAR 7044, the full maneuver updates at 068/214136Z and at 068/214421Z failed due to FHST-1. No attitude error was seen. The following guide star acquisition was successful. 2.3 Operations Notes: Using ROP SR-1, the SSR EDAC error counter was cleared three times. 3.0 SIGNIFICANT FORTHCOMING EVENTS: Continuation of normal science observations and calibrations. /DMH