HUBBLE SPACE TELESCOPE DAILY REPORT #2593 PERIOD COVERED: 0000Z (UTC) 03/31/00 - 0000Z (UTC) 04/03/00 Daily Status Report as of 094/0000Z 1.0 OBSERVATIONS SCHEDULED AND ACCOMPLISHED: 1.1 Completed Five Sets of WF/PC-2 8460 (Cycle 8 Supplemental Darks pt2/3) The WF/PC-2 was used to obtain three dark frames every day to provide data for monitoring and characterizing the evolution of hot pixels. The observations completed with no reported problems. 1.2 Completed Five Sets of STIS/CCD 8217 (Tests of Stellar Models Using Four Extremely Massive Spectroscopic Binaries in the R136 Cluster) The Space Telescope Imaging Spectrograph (CCD) was used to observe four non-interacting double-lined spectroscopic binaries discovered in the R136 cluster by the Cycle 6 FOS spectroscopy. The proposal completed nominally. 1.3 Completed Eight 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. As described in 2.1 and HSTAR 7563, the acquisition for the final iteration of this proposal defaulted to fine lock backup on one FGS, possibly affecting two observations. Otherwise, the observations were executed as scheduled, and no further anomalies were noted. 1.4 Completed Three Sets of STIS/CCD 8439 (Bias Monitor-Part 2 C8) The Space Telescope Imaging Spectrograph (CCD) was used to monitor the bias in the 1x1, 1x2, 2x1, and 2x2 bin settings at gain=1, and 1x1 at gain = 4, to build up high-S/N superbiases and track the evolution of hot columns. The proposal completed with no reported problems. 1.5 Completed Three Sets of STIS/CCD 8228 (The Black Hole Versus Bulge Mass Relationship in Spiral Galaxies) The Space Telescope Imaging Spectrograph (CCD) was used to make observations of the galaxies NGC-4303, NGC-5713 and NGC-3887 in order to study the black hole versus bulge mass relationship in spiral galaxies. Wavelength calibration images were also taken. The observations were executed as scheduled, and no anomalies were noted. 1.6 Completed Three Sets of WF/PC-2 8445 (WF/PC-2 Cycle 8 Earth Flats) The WF/PC-2 was used to make Cycle 8 Earth flat calibration observations. This is to obtain sequences of earth streak flats to construct high quality flat fields for the WF/PC-2 filter set. The observations were executed as scheduled, and no anomalies were noted. 1.7 Completed WF/PC-2 8444 (WF/PC-2 CYCLE-8 Internal Monitor) The WF/PC-2 was used to make a bias, and an internal flat, observation as part of a Cycle-8 monitoring program to monitor the health of the cameras. A variety of internal exposures are obtained in order to provide a monitor of the integrity of the CCD camera electronics in both bays {gain 7 and gain 15}, a test for quantum efficiency in the CCDs, and a monitor for possible buildup of contaminants on the CCD windows. The observations were executed as scheduled, and no anomalies were noted. 1.8 Completed Five 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. 1.9 Completed Two Sessions of FGS 8527 (Near Term Stability) FGS-2R was used to determine the near term stability of the instrument. The goals are twofold: {1} to establish the baseline Long Term Stability measurement for the new FGS and monitor changes in the relative plate scale and distortion since the SMOV MiniOFAD; and {2} to monitor changes in the transfer function over months. The proposal completed nominally. 1.10 Completed Three Sets of STIS/CCD 8796 (POMS Test Proposal: STIS Non-Scripted Parallel Proposal Continuation IV) The Space Telescope Imaging Spectrograph (CCD) was used in the parallel mode to make some low galactic latitude archive observations. The observations were executed as scheduled, and no anomalies were noted. 1.11 Completed Six Sets of STIS/CCD 8549 (POMS Test Proposal: Non-Scripted Parallel Proposal Continuation I) The Space Telescope Imaging Spectrograph (CCD) was used to make low galactic latitude, non-scripted parallel observations as part of a POMS test proposal. The observations were completed as planned, and no anomalies were reported. 1.12. Completed STIS/CCD 8176 (Confirmation and Characterization of Brown Dwarfs and Giant Planets from NICMOS 7226/7227) The Space Telescope Imaging Spectrograph (CCD) was used to make confirmation and characterization observations of object GL577B. This is a continuation of NICMOS 7226/7227 using the STIS. A systematic search for giant planet and brown dwarf companions to stars in the solar neighborhood was the cornerstone of the NICMOS IDT's Environments of Nearby Stars {EONS} program. The observations were completed as planned, and no anomalies were reported. 1.13 Completed WF/PC-2 8230 (Snapshot Survey of Dynamically Close Galaxy Pairs from z=0.1 to z=0.5) The WF/PC-2 was used to make snapshot survey observations of galactic cluster Gal-Clus-0. This is to obtain snapshot images of a large, well-defined, and dynamically selected sample of close galaxy pairs at moderate redshift. The observations were executed as scheduled, and no anomalies were noted. 1.14 Completed Four Sets of WF/PC-2 8059 (POMS Test Proposal: Targeted Parallel Archive Proposal) The WF/PC-2 was used to observe the parallel opportunities available in the neighborhood of bright galaxies are treated in a slightly different way from the normal pure parallels. Local Group galaxies offer the opportunity for a closer look at young stellar populations. Narrow-band images in F656N can be used both to identify young stars via their emission lines, and to map the gas distribution in star-forming regions. The observations completed nominally. 1.15 Completed Two Sets of STIS/CCD/MA1/MA2 8165 (Pervasive Hot Gas Hidden in Galaxy Groups: A Substantial Baryon Reservoir?) The Space Telescope Imaging Spectrograph (CCD, MA1 and MA2) was used to make observations of galactic cluster H1821+643 to look for pervasive hot gas in the intracluster media. Cosmological simulations predict that at z ~ 0, most groups of galaxies should be embedded in large filaments and sheets of shock heated gas at 10^5 -- 10^6 ^degrees K. A wavelength calibration image was also taken. The observations were executed as scheduled, and no anomalies were noted. 1.16 Completed WF/PC-2 8696 (Disentangling the Bulge and NGC 6528 - A Proper Motion Study) The WF/PC-2 was used to obtain second epoch observations of the Galactic globular cluster NGC 6528. These will be used to obtain proper motions of the cluster relative to the background bulge field and thus provide, for the first time, a color-magnitude diagram of NGC 6528 free from background stars. The proposal completed nominally. 1.17 Completed WF/PC-2 8263 (Snapshots of Sub-mJy Starburst Galaxies) The WF/PC-2 was used to make observations of the starbursting galaxy GAL-011126. Some of the most ambitious and widely cited extragalactic observations in recent years have been the constraints made on the star formation history of the Universe. The observations were completed as planned, and no anomalies were reported. 1.18 Completed WF/PC-2 8270 (Proper Motion of the Leo II Dwarf Spheroidal) The WF/PC-2 was used to continue the investigation into the proper motion of distant satellites of the Milky Way with a series of HST snapshots around faint galaxies within the Leo II astrometric field. A proper motion for Leo II will be determined by combining images from 111 Palomar 200" photographic plates taken by Baade between 1950-1959 with the HST snapshots. Only with the fine pixel scale of HST can we realistically hope to match the exquisite Baade images, which were all taken on the very best nights from a decade of Baade's allotment of about forty 200 arcsecond nights a year. The observations completed with no reported problems. 1.19 Completed WF/PC-2 8457 (UV Earth Flats) The WF/PC-2 was used to obtain a series of Ultraviolet Earth flats. The observations were completed with no reported problems. 1.20 Completed STIS/CCD 8418 (CCD Sensitivity Monitor C8) The Space Telescope Imaging Spectrograph (CCD) was used to make observations of standard source AGK+81D266 as part of a CCD sensitivity-monitoring program in Cycle-8. The sensitivity of each CCD grating mode is monitored to detect any change due to contamination or other causes. A wavelength calibration image was also taken. The observations were completed as planned, and no anomalies were reported. 1.21 Completed WF/PC-2 8322 (The Distance to NGC 2841: Improving the TF Calibration and Definitively Testing MOND) The WF/PC-2 was used to measure a distance to the spiral galaxy NGC 2841 using Cepheid variables. NGC 2841 provides a unique opportunity to simultaneously probe three separate phenomenon in extragalactic astronomy: 1} It will provide the highest rotational velocity data point for the Cepheid based calibration of the I-band Tully-Fisher relation and thus will firmly determine if this relation experiences curvature or remains linear all the way out to high rotational velocities. 2} It has hosted two SN Ia events; both of which have good photometry {1957A and 1972R}- this significantly adds to the number of calibrators for the SN Ia distance scale; 3} If its distance can be shown to be significantly less than 19.5 MPC, then MOND can be definitively ruled out because NGC 2841 will require a value of a_o substantially in excess of the empirically determined "universal" value. The observations completed nominally. 1.22 Completed WF/PC-2 8100 (Calibration of Nearby Type Ia Supernovae as Standard Candles: The Next Step) The WF/PC-2 was used to continue the calibration experiment for M{ max} of type Ia supernovae {SNe Ia} by determining Cepheid distances to their parent galaxies. The proposal completed nominally. 1.23 Completed STIS/CCD/MA1 8311 (Moderate Redshift Analogs To Lyman-Break Galaxies?) The Space Telescope Imaging Spectrograph (CCD and MA1) was used to determine whether high luminosity galaxies selected using rest ultraviolet luminosity at low-to-moderate redshift {0.2