HUBBLE SPACE TELESCOPE DAILY REPORT #1949 PERIOD COVERED: 0000Z (UTC) 08/25/97 - 0000Z (UTC) 08/26/97 Daily Status Report as of 238/0000Z 1.0 ACTIVITIES SCHEDULED AND ACCOMPLISHED: 1.1 Completed WF/PC-2 6431 (Determination of the Extragalactric Distance Scale) The WF/PC-2 was used to make observations of the galaxy NGC-1425 to be used in measuring the periods of Cepheid variable stars within this galaxy. This will allow for a more accurate estimate of the distances to these galaxies through the period-luminosity relation for the Cepheid stars. The observations were executed as scheduled, and no anomalies were noted. 1.2 Completed NIC/1/2/3 7726 (NICMOS One Orbit Parallel) The Near Infrared Camera (Cameras One, Two and Three) was used to make a one orbit parallel calibration observations. The observations were executed as scheduled, and no anomalies were noted. 1.3 Completed Six Sets of NIC/1/2/3 7688 (ACCUM Darks) The Near Infrared Camera (Cameras One, Two, and Three) was used to measure dark current on individual pixels for a limited set of ACCUM exposure times in order to conduct an internal calibration of ACCUM mode. The observations were completed as scheduled, with no problems reported. 1.4 Completed STIS/CCD 7782 (STIS Non-Scripted Parallel Archive Proposal - Half Orbit) The Space Telescope Imaging Spectrograph (CCD) was used for a non-scripted parallel archive proposal (one-half orbit). The observations were executed as scheduled, and no anomalies were noted. 1.5 Completed Five Sets of NIC/1/2/3 7729 (NICMOS Short One Orbit Parallel) The Near Infrared Camera (Cameras One, Two, and Three) was used to obtain "JHK" imaging of sky regions while another instrument was prime. These observations were part of the short NICMOS one-orbit parallel program. The observations were executed as scheduled, and no anomalies were noted. 1.6 Completed Two Sets of STIS/CCD 7601 (CCD Dark and Bias Monitor) The Space Telescope Imaging Spectrograph (CCD) was used to conduct bias and dark monitoring. Also, observations were made to track the growth of hot pixels on the CCD in general and within the various target acquisition apertures specifically. The observations were completed as planned, and no anomalies were reported. 1.7 Completed NIC/1/2/3 7789 (MULTIACCUM Dark Characterization of Pedestal) The Near Infrared Camera (Cameras One, Two, and Three) was used to take a series of dark images to characterize the pedestal problem fix which was installed in NICMOS flight software version 4.08, installed last week. The observations were completed as planned with no reported anomalies. 1.8 Completed Three Sets of WF/PC-2 7620 (WF/PC-2 CYCLE 7 Standard Darks) The WF/PC-2 was used to make a series of Cycle 7 standard dark calibration images. This calibration program obtains dark frames every week in order to provide data for the ongoing calibration of the CCD dark current rate, and to monitor and characterize the evolution of hot pixels. The observations were executed as scheduled, and no anomalies were noted. 1.9 Completed NIC/1/2/3 7412 (An HST/NICMOS Search for Young Brown Dwarfs and Giant Planets) The Near Infrared Camera (Cameras One, Two and Three) was used to make observations taken in parallel with the prime science observations to be part of a survey to look for large planets and/or small brown dwarf stars which are in orbit around T-Tauri class stars. At an age of 2 to 20 million years these low-mass companions will be considerably brighter than more evolved brown dwarfs or giant planets orbiting main-sequence stars, and hence will be much easier to detect. The observations were completed as planned, and no anomalies were noted. 1.10 Completed Eight Sets of STIS/MA2 7604 (Cycle 7 MAMA Dark Measurements) The Space Telescope Imaging Spectrograph (MA2) was used to make MAMA dark measurements. These darks will be used in later image reductions and also trended over the instrument's life time as an indicator of the detector's degradation or damage. The observations were completed as scheduled, and no problems were reported. 1.11 Completed Three Sets of WF/PC-2 7621 (WF/PC-2 Cycle 7 Supplemental Darks PT1/3) The WF/PC-2 was used to make supplemental dark calibration images. This set of calibrations is intended to obtain three dark frames every day to provide data for monitoring and characterizing the evolution of hot pixels. The observations were executed as scheduled, and no anomalies were noted. 1.12 Completed WF/PC-2 6936 (UV Throughput) The WF/PC-2 was used to make ultraviolet observations of the standard star GRW+70D582 in order to measure the system's throughput. These observations will be used to determine the wavelength dependence of the throughput across the bandpass. The observations were executed as scheduled, and no anomalies were noted. 1.13 Completed Five Sets of STIS/CCD 7659 (Daily Darks to Update Acquisition Bad Pixel Table) The Space Telescope Imaging Spectrograph (CCD) was used to make dark calibration images in order to update the acquisition bad pixel table. Daily hot pixel lists can also be used for science data analysis. The observations were executed as scheduled, and no anomalies were noted. 1.14 Completed NIC/1/2/3 7447 (The Cosmological Evolution of Quasar Host Galaxies) The Near Infrared Camera (Cameras One, Two and Three) was used to make observations of galaxy SPG5-46 as part of a survey to study the cosmological evolution of galaxies which host quasars. Other point spread function observations were taken to test the calibration of the cameras. The observations were executed as scheduled, and no anomalies were noted. 1.15 Completed WF/PC-2 6194 (WF/PC-2 Cycle 5: Polarization Proposal) The WF/PC-2 was used to make polarization observations of star BD+64D106 at four different spacecraft roll angles. This should permit a detailed and independent calibration of each polarizer quad. The observations were executed as scheduled, and no anomalies were noted. 1.16 Completed NIC/1/2/3 7608 (NICMOS Focus Monitoring) The Near Infrared Cameras (Cameras One, Two, and Three) was used to determine and monitor the optimal focus and tilt settings for all three NICMOS cameras. This proposal is built to run NIC/1/2/3 sweeps on a 2-week basis. The obserservations completed without incident with no reported anomalies. 2.0 FLIGHT OPERATIONS SUMMARY: 2.1 Guide Star Acquisitions: Scheduled Acquisitions : 8 Successful : 8 Scheduled Reacquisitions : 8 Successful : 8 2.2 FHST Updates: Scheduled : 12 Successful : 9 The updates scheduled at 237/1505Z, 237/1507Z, and 237/1628Z failed. 2.3 Operations Notes: There were no reported operational problems. 3.0 SIGNIFICANT FORTHCOMING EVENTS: Continuation of normal science observations and calibrations. /DMH